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Topics - AbruptSLR

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1
Consequences / 2017 ENSO
« on: January 07, 2017, 03:08:28 AM »
As it is 2017, I thought it time to open a new ENSO thread & I start by noting the per the attached plot issued today by the BoM; the 30-day moving average SOI has drifted up to +6.3:

2
The Quintillion Subsea Cable System should soon connect Tokyo to London with fiber-optic cables; thanks to global warming opening up the Northwest Passage in a few short years time:

http://motherboard.vice.com/read/the-world-is-melting-but-at-least-well-have-better-internet-because-of-it

Extract: "Climate shift is mostly bad news, but it is now giving internet-lovers a half-hearted reason to cheer. “Thanks” to a warming planet and retreating pack-ice in the Arctic Ocean, installation of a 15,000 km undersea fiber-optic cable directly linking Europe and Asia for the first time is now possible.
It’s easy to forget that today’s internet is supported by a vast network of cables zig-zagging over 600,000 miles along our ocean floor. These tangled strips of wire now support basically all of our international communications, and as the internet has grown over the past two decades, so too has the size of this submarine network.
Until recently, the ships required to install these cables couldn’t navigate the icy Northwest Passage, the arctic sea route connecting the Atlantic and Pacific Oceans. But today that’s no longer the case."

See also (the source of the attached image):

http://fm.kuac.org/post/anchorage-firm-outlines-plans-bring-broadband-five-alaska-communities



3
Spring 2016 / Systemic Isolation
« on: June 11, 2016, 06:14:58 PM »
I made the following post in the "Arctic Sea Ice Humor" thread, where I tried to use "The Matrix" as a metaphor as a mental system that has trapped/isolated individuals into a materialistic/hedonistic way of thinking/being; rather than becoming "unplugged" from the system/matrix so that they could express their free will as Neo learns to do.  And in this thread I hope to engage in a multi-layer/level (technical/philosophical/political/psychological/scientific etc, e.g. see the link to Elon Musk's opinion that we do in fact inhabit a "computer" generated reality) discussion of how systemic thinking tends to cling to old values/thinking resulting in individual/group isolation from an ever changing reality, which results in suffering, rather than in living a life unburdened by bias & limitations.

Re-post:

"And many of them are so inert, so hopelessly dependent on the system that they will fight to protect it." Morpheus, The Matrix


Edit: See also

http://www.newyorker.com/books/joshua-rothman/what-are-the-odds-we-are-living-in-a-computer-simulation

4
Antarctica / Southern Ocean Cold Spots
« on: May 20, 2016, 11:10:40 PM »
I am starting this thread with the attached CCI-Reanalyzer SH 5-day SAT Anom forecast issued May 20 2016 as it clearly indicates that the: Ronne-Flichner, the Ross, and the Amery, ice shelves are already making significant ice meltwater contributions to the Southern Ocean without making any contribution to SLR.  This ice shelf meltwater is already clearly contributing to the Hansen's ice-climate feedback and is suppressing the measures Surface Air Temperatures (SAT) in the Southern Hemisphere (SH):

5
Spring 2016 / Human Stupidity
« on: May 19, 2016, 12:15:50 AM »
When it is human stupidity that has caused climate change, why do so many think that humans will be able to avoid exceeding the 2C target?

6
Consequences / Mega ENSO
« on: March 06, 2016, 09:52:26 PM »
I know nothing about Mega ENSOs, so I will begin learning by compiling related articles:


Yefan Zhou andZhiwei Wu (2016), "Possible impacts of mega-El Niño/Southern Oscillation and Atlantic multidecadal oscillation on Eurasian heat wave frequency variability", Quarterly Journal of the Royal Meteorological Society, DOI: 10.1002/qj.2759

http://onlinelibrary.wiley.com/doi/10.1002/qj.2759/abstract

Abstract: "Identifying predictability sources of heat wave variations is a scientific challenge and of practical importance. This study investigates the summertime heat wave frequency (HWF) over Eurasia for 1950–2014. The Eurasian HWF is dominated by two distinct modes: the interdecadal (ID) mode featured by an increasing pattern overall, centered around eastern Europe-central Asia and Mongolia-southwestern China; the interannual (IA) mode resembling a tri-pole anomaly pattern with three centers over western-northern Europe, northeastern Asia and East Asia. The ID mode is found to be influenced by mega-El Niño/Southern Oscillation (mega-ENSO) and the Atlantic multidecadal oscillation (AMO), and the latter has far more effect, whereas the IA mode is connected with mega-ENSO.

Further analysis suggests that mega-ENSO variations can incite a Gill-type response spreading to Eurasia, while the AMO changes cause eastward-propagating Rossby wave trains toward Eurasia. These two teleconnection patterns together contribute to the large-scale circulation anomalies of the ID mode, and those related to the IA mode arise from the teleconnection pattern excited by mega-ENSO. A strong mega-ENSO triggers subsidence with high pressure anomalies, warms the surface and increases the HWF significantly over northeastern Asia particularly. Likewise, the warm AMO-induced circulation anomalies engender surface radiative heating and HWF growth in most of Eurasian continent except some localized Siberian and Asian regions. The situation is opposite for a weak mega-ENSO and AMO. Those models from phase 5 of the Coupled Model Intercomparison Project (CMIP5) which realistically capture the features of the ID mode can reproduce the AMO-like sea surface temperature anomalies (SSTAs), while signals resembling mega-ENSO are found in those with favorable capability of simulating the IA mode. On the contrary, these relevant SSTAs linked to the respective modes vanish in the models with little skills. Thus, mega-ENSO and the AMO might provide two critical predictability sources for heat waves over Eurasia."

7
I have repeated noted (in numerous folders/threads) that virtually all of the AR5 process-based climate projections, and associated literature, present at best low-bound estimates of potential climate consequences.  These lower-bound projections do not adequately account for numerous considerations include: phases of decadal cycles (ala the PDO, etc), initial model conditions and boundary effects, limited understanding of non-linear feedback mechanisms, limited understanding of aerosol radiative forcing mechanisms; limited understanding of anthropogenic radiative forcing scenarios, misinterpretations of paleo-data, climate model limitations, etc, etc.

The next best thing to developing upper-bound projections would be to progressively calibrate each phase of the DOE's non-linear ACME program that its hind-casts reasonably match both observed, and paleo, data and then to use the progressively calibrated ACME program to make improved projections. 

This requires the development & use of "climate model test beds", such as that discussed in the linked EOS article, which for ACME, will be ready for use by the end of 2016.  With this in mind, I am opening this new thread to discuss the topic of how to better calibrate state of the art nonlinear Earth System Models, ESMs, using "climate model test beds" (see the attached image for the ACME climate model test bed architecture):


https://eos.org/project-updates/better-tools-to-build-better-climate-models

Extract: "To determine the accuracy of predictions, results are validated by comparing them to present-day observations.  As new data are fed to the model and scientific understanding of climate systems evolves, new information gets built into the model, and the testing and validation continue.

One of the most resource-intensive aspects of climate modeling is the creation of a system for calibrating climate models, where model simulations are used to validate model output against observational data sets that span the globe. We call this system a “climate model test bed.” Such test bed environments typically evaluate each component of the model in isolation, using a skeleton framework that makes the module behave as if it were functioning within the larger program.

The prototype test bed team is now under the banner of the newly formed Accelerated Climate Modeling for Energy (ACME) project, under the auspices of the U.S. Department of Energy’s Office of Science. Under ACME, the team will continue its efforts to deliver an advanced model development, testing, and execution workflow and data infrastructure production test bed for DOE climate and energy research needs. We anticipate rolling out the test bed by end of 2016 for ACME use."

8
Policy and solutions / Graphene and Renewable Power
« on: November 11, 2015, 08:23:01 PM »
The linked SkS article discusses the promising future (2030?) of graphene & renewable electric power (including PV, Batteries and Electric Motors):

https://www.skepticalscience.com/Graphene-SkS.html

Extract: "Commercialisation of graphene technology has begun and is continuing to make advances which are likely to see the electric motor (95% efficient) replace the internal combustion engine (20% efficient) and fossil fuelled power stations in the 2020’s. These disruptions could be largely completed by 2030 followed by clean electrification of the most demanding of industries and equipment.

The fundamental reason why graphene technology will succeed is displacing fossil fuels, where other technologies have failed, is because of the extraordinary properties of graphene and its composites. These make it comparatively efficient in the generation and storage of electricity and, for many other applications, it is a cheaper and more versatile material."

9
Policy and solutions / Possible Iceberg Wrangling in the Southern Ocean
« on: September 05, 2015, 05:24:43 PM »
Hansen et al. (2015) (see the discuss in the Consequence folder of this forum at the first link below), have cited some of the possible positive feedback mechanisms and negative consequences of the ice sheets abruptly losing ice mass this century.  In that "Hansen et al paper: 3+ meters SLR by 2100", I speculated on the possibility of wrangling Southern Ocean icebergs to both reduce the positive feedback mechanisms and the negative climate consequences cited by Hanse et al. (2015).  As it seems inappropriate to explore this topic in the "Consequence" folder, I open this thread on "Possible Iceberg Wrangling in the Southern Ocean" in this "Policy and solutions" folder, in order to discuss: (a) the nature of Southern Ocean icebergs both now & in the future; and (b) the feasibility of wrangling Southern Ocean icebergs either as a future freshwater source and/or as a form of geoengineering.

http://forum.arctic-sea-ice.net/index.php/topic,1327.250.html


As most readers are likely unfamiliar with the nature of Southern Ocean icebergs, I begin with the first link to NASA Earth Observatory that discusses how the U.S. National ice Center (NIC) tracks icebergs adrift off the coast of Antarctica that meet the 19-kilometer minimum criteria for tracking (see the associated image of iceberg B-34 breaking off the Getz Ice Shelf and associated extracts).

http://earthobservatory.nasa.gov/IOTD/view.php?id=85727

Extract related to the first image: "On March 6, 2015, the U.S. National Ice Center (NIC) discovered a new iceberg adrift off the coast of Antarctica. Measuring 27 kilometers (17 miles) long, iceberg B-34 meets the 19-kilometer minimum required for tracking by the NIC.
The berg appears to have fractured from West Antarctica’s Getz Ice Shelf and moved out into in the Amundsen Sea sometime in mid- to late-February 2015. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra and Aqua satellites acquired these images spanning the calving event. The first image (left) shows the iceberg on February 16, when it was still attached to the ice shelf. By February 28 (middle), it appears to have separated somewhat. By March 5 (right), it is floating freely."


Extract: "B-34 is the 34th iceberg from the “B” quadrant of Antarctica (located between 90 degrees East and 180 degrees) to be tracked by the NIC. The new berg is still smaller, however, than the much older B-15T—a fragment of B-15 that initially broke off from the Ross Ice Shelf in March 2000.
Large icebergs can have large-scale impacts on the Southern Ocean. For example, as the bergs melt, the addition of cold, fresh water to the saltwater ocean can affect ocean currents and circulation. Researchers have shown, however, that even more fresh water comes from the melting of smaller and much more numerous bergs.

References
•   NASA Earth Observatory (2015, April 12) Iceberg B-15T Still Adrift. Accessed April 20, 2015.
•   Tournadre, J. et al. (2015, March 26) Large icebergs characteristics from altimeter waveforms analysis. Journal of Geophysical Research: Oceans, 120 (3), 1954-1974.
•   U.S. National Ice Center (2015, March 6) Iceberg B-34 Found in the Amundsen Sea. Accessed April 20, 2015."

The next link leads to a US Coast Guard site that tracks the location of icebergs (focused on the North Atlantic) which provides the second attached image showing the location of large Southern Ocean icebergs in 2011, and I note that such large icebergs can stay adrift for decades while they slowly melt.

http://www.navcen.uscg.gov/?pageName=IcebergLocations

Caption for Second image: "Typical distribution of icebergs around the Antarctic continent"

10
Science / The Science of Aerosols
« on: September 03, 2015, 04:35:05 PM »
As discussions of the influence of aerosols is rather scattered though out this forum, I thought that it would be helpful to open a thread focused on this important anthropogenic forcing mechanism, and I open this thread with the following about contrails:

The linked article (with an open access pdf) discusses how global warming will increase the potential formation of contrails in some parts of the world and decrease it in other parts.

Irvine, E. A. and Shine, K. P.: Ice supersaturation and the potential for contrail formation in a changing climate, Earth Syst. Dynam., 6, 555-568, doi:10.5194/esd-6-555-2015, 2015.

http://www.earth-syst-dynam.net/6/555/2015/esd-6-555-2015.html

Abstract. Ice supersaturation (ISS) in the upper troposphere and lower stratosphere is important for the formation of cirrus clouds and long-lived contrails. Cold ISS (CISS) regions (taken here to be ice-supersaturated regions with temperature below 233 K) are most relevant for contrail formation. We analyse projected changes to the 250 hPa distribution and frequency of CISS regions over the 21st century using data from the Representative Concentration Pathway 8.5 simulations for a selection of Coupled Model Intercomparison Project Phase 5 models. The models show a global-mean, annual-mean decrease in CISS frequency by about one-third, from 11 to 7% by the end of the 21st century, relative to the present-day period 1979–2005. Changes are analysed in further detail for three subregions where air traffic is already high and increasing (Northern Hemisphere mid-latitudes) or expected to increase (tropics and Northern Hemisphere polar regions). The largest change is seen in the tropics, where a reduction of around 9 percentage points in CISS frequency by the end of the century is driven by the strong warming of the upper troposphere. In the Northern Hemisphere mid-latitudes the multi-model-mean change is an increase in CISS frequency of 1 percentage point; however the sign of the change is dependent not only on the model but also on latitude and season. In the Northern Hemisphere polar regions there is an increase in CISS frequency of 5 percentage points in the annual mean. These results suggest that, over the 21st century, climate change may have large impacts on the potential for contrail formation; actual changes to contrail cover will also depend on changes to the volume of air traffic, aircraft technology and flight routing.

11
Science / Hydrogen Sulfide Producing Bacteria in the Ocean
« on: August 30, 2015, 10:43:25 AM »
Robert Scribbler posts a disturbing article that hydrogen sulfide producing bacteria are starting to show-up on the US West Coast:

http://robertscribbler.com/

Extract: "Are we already starting to awaken some of the horrors of the ancient hothouse ocean? Are dangerous, sea and land life killing, strains of primordial hydrogen sulfide producing bacteria starting to show up in the increasingly warm and oxygen-starved waters of the US West Coast? This week’s disturbing new reports of odd-smelling, purple-colored waves appearing along the Oregon coastline are a sign that it may be starting to happen.



The purple sulfur reducing bacteria, though not dangerous themselves, live in a kind of conjoined relationship with the much more deadly hydrogen sulfide producing bacteria. The purple, is therefore, a tell-tale of the more deadly bacteria’s presence. And hydrogen sulfide producing bacteria may well be the most dangerous organism ever to have existed on the planet — largely responsible for almost all the great extinction events in Earth’s deep history. For hydrogen sulfide itself is directly toxic to both land and ocean-based life. Its deadly effects are increased at higher temperatures. And not only is it directly toxic in both water and air, if it enters the upper atmosphere it also destroys the ozone layer."


12
Science / Adapting to the Anthropocene
« on: July 06, 2015, 12:08:32 AM »
To find other discussions on key elements of adapting to the rapidly changing Anthropocene, see also the following linked threads:

- Scientifically modelling (approximating) the anthropogenic – Earth Systems interactions discussed here: (http://forum.arctic-sea-ice.net/index.php?topic=1306.msg55632#msg55632)
- Understanding/defining the nature of the Early Anthropocene as discussed here (http://forum.arctic-sea-ice.net/index.php/topic,852.0.html), and
- Understanding the associated Existential Risks of the Anthropocene are discussed here (http://forum.arctic-sea-ice.net/index.php/topic,1307.0.html).

With such background discussions in mind, this thread focuses on how our socio-economic system may likely evolve/change to adapt to the Anthropocene (including but not limited to climate change) through about 2100 .  In this regards I plan to discuss:
(1) representative background on how AI and cyborg technology may likely interact with the modern human mind-body dynamic to change in new ways; and
(2) representative examples of anthropological findings illustrate how evolution has shaped the mind-body dynamic in modern humans;
(3) representative background on how morality and "mindfulness" techniques are already impacting modern business practices, information theory, psychology, sociology, and neuroscience of well-being can foster a thriving, resilient, and compassionate global socio-economic system.

As I believe that the Anthropocene is best characterized by the Information Age that our socio-economic system has moving into, I will begin this thread with an initial linked article about how the future rich (this century or two) may use AI & cyborg technology to assume behavior that exceed current social expectations:

http://rt.com/uk/263133-rich-human-god-cyborgs/
Extract: "Rich people living 200 years from now are likely to become “god-like” immortal cyborgs, while the poor will die out, an historian has claimed.
Yuval Noah Harari, a professor at the Hebrew University of Jerusalem, said the merger of humans and machines would be the greatest evolution since the appearance of life.
He added the greatest minds in computer engineering already believe death is a mere technological problem with a solution.
Harari said advances in technology will enable humans to become god-like creatures, as different from today’s humans as chimpanzees are from us.

During his talk, Harari said humans are programmed to be dissatisfied in life. Even when humans gain pleasure and achievements, they want more.
“I think it is likely in the next 200 years or so Homo sapiens will upgrade themselves into some idea of a divine being, either through biological manipulation or genetic engineering of by the creation of cyborgs, part organic part non-organic,” he told the audience.
“It will be the greatest evolution in biology since the appearance of life. Nothing really has changed in four billion years biologically speaking. But we will be as different from today’s humans as chimps are now from us.”
However, Harari said only the wealthiest would benefit from ‘cyborg’ technology, making the gap between rich and poor in society even wider.
In the future the rich may be immortal while the poor would die out, he said.
Harari’s book argues that humans are successful as a species because of their imagination and ability to create fictions.
He cites religion, money and the concept of human rights as “fictions” which hold society together but have no basis in nature.
Speaking at Hay, he said: “God is extremely important because without religious myth you can’t create society. Religion is the most important invention of humans. As long as humans believed they relied more and more on these gods they were controllable.
“But what we see in the last few centuries is humans becoming more powerful and they no longer need the crutches of the gods. Now we are saying we do not need God, just technology.
“The most interesting place in the world from a religious perspective is not the Middle East, it’s Silicon Valley where they are developing a techno-religion. They believe even death is just a technological problem to be solved,” he added. "

Starting this thread with such a linked article may seem like an artificial "deus ex machine" device; however, I sincerely believe that developments in information theory will have a major impact on our coming socio-economic system for good (discussed in this thread) and bad (see the Anthropogenic Existential Risk thread here: http://forum.arctic-sea-ice.net/index.php/topic,1307.0.html )

https://en.wikipedia.org/wiki/Deus_ex_machina
Extract: "Deus ex machina: meaning "god from the machine".  The term has evolved to mean a plot device whereby a seemingly unsolvable problem is suddenly and abruptly resolved by the contrived and unexpected intervention of some new event, character, ability or object."

13
Science / Anthropogenic Existential Risk
« on: July 05, 2015, 11:51:15 PM »
Anthropogenic Existential Risks are associated with the potential, or effective, extinction of the current human race; which includes the risk of replacement by (or domination by) a subsequent species.  Such risks include consideration of the coupled risk between climate change as a stress riser and other potential anthropogenic risks to the species including: (a) biotech, bioterror, bioerror, (b) nuclear risks, (c) non-renewable resource depletion, (d) information era risks: AI, robotics, cyborgs, machine learning, (e) genetic engineering, (f) geoengineering, (g) collapse of environmental conditions and (f) nanotechnology.  Specifically, this thread considers the probably rapid convergence of such multiple trend-lines towards a possible tipping point before 2100.

Such existential risks are actively being evaluated by such as:
(1) The Centre for the Study of Existential Risk (CSER)
http://en.wikipedia.org/wiki/Centre_for_the_Study_of_Existential_Risk
and
(2) Global Catastrophic Risk Institute (GCRI)
http://gcrinstitute.org/
http://gcrinstitute.org/publications/
and
(3) The Future of Humanity Institute (FHI), at Oxford

Also see the FHI associated image of the scope and severity of global threats:
http://www.fhi.ox.ac.uk/
http://www.fhi.ox.ac.uk/research/publications/

For a quick introduction to this type of Existential Risk evaluation see:
http://qz.com/386637/meet-the-people-trying-to-prevent-humanity-from-destroying-itself/

… a timeline that showed the likelihood, according to each FHI researcher, that the human race would go extinct in the next 100 years. They asked me not to publish it. (Most said the chances were quite low, but one person put it at 40%.)
….
And when what you’re worried about is human extinction, the bar for what counts as a catastrophe is high—brutally high. Take, for example, global warming. “Climate change could constitute an existential risk if it’s worse than we expect and there’s a feedback loop that causes temperatures to rise by 20°C,” Snyder-Beattie says. (We’re currently heading for a rise of between 2-4°C.)



More information about Extreme Climate from CSER can be found at:
http://cser.org/emerging-risks-from-technology/extreme-tail-climate-risks/

See also:
http://www.ted.com/talks/martin_rees_asks_is_this_our_final_century?language=en
http://www.csap.cam.ac.uk/news/article-time-ditch-2-degree-warming-goal/
http://www.nature.com/news/climate-policy-ditch-the-2-c-warming-goal-1.16018
http://www.fhi.ox.ac.uk/Existential-risk-and-existential-hope.pdf

An example of evaluating the risks associated with AI development can be found in the following linked video by Prof Stuart Russell: Long-term Control Benefit (dis-benefit) of Artificial Intelligence, Machine Intelligence (UC Berkeley) (which tries to address Elon Musk's concern but could also be applied to climate change or other existential risks).  AAAI now recommends inclusions of ethical impacts on science (because AI is making progress)
https://www.youtube.com/watch?v=GYQrNfSmQ0M&list=PLcBS5tXy2Dy6t2jNX4VVOP49_vKoGOcBP


Furthermore, Dr Toby Ord indicates that Existential Risk this century is substantial as included below:
Dr Toby Ord: "Will we cause our own extinction? Natural versus Anthropogenic Extinction Risks" (Prof at Oxford University): Across the board accumulation of risk of Anthropogenic human extinction; need to put bounds of what these cumulative risks are this century.  Natural (asteroid, volcanoes (nuclear winter effect of both volcanoes & impacts) or super volcanoes, seismic; replacement by a superior species to humans), but anthropogenic risks are more likely.  Homo Sapiens Sapiens have been around for 200,000 yrs or 2,000 centuries to calculate risks use Laplace to calculate Bayesian risks (use Jeffreys prior) which gives a Natural Risk of 1 in 4002 (0.02% per century).  Alternately a mass extinction would give a 0.0001% risk (assuming natural risks are not increasing with time, except for natural pandemics whose risks are likely increasing with time at the moment).  Electro-magnetic pulse knocking out communications & consequently infrastructure.  Replacement of homo sapiens sapiens by a genetically superior race.
Anthropogenic risks (not enough data for Bayesian calculations, & p-value does not clarify what is the upper bound).  We need to have both an upper & a lower bound.

Examples: Nuclear winter, engineered pandemics, Artificial Intelligence (general super intelligence, difficult to align AI values with human goal).  Martin Rees estimates a 50% chance of human extinction by 2100; GCR estimate is 20% by 2100, Stern report estimates 10% by 2100.

14
Science / Modelling the Anthropocene
« on: July 05, 2015, 11:24:49 PM »
With a refreshed perspective from my 6-week break from posting, I have decided to focus for a while on emphasizing the nature, reality and implications of the Anthropocene; as examining mankind's decision making processes can no longer be marginalized by science if we are to reasonably understand our increasingly dominant impact on nature.  In this light, I have made new posts to:  "The Early Anthropocene" thread (here: http://forum.arctic-sea-ice.net/index.php/topic,852.0.html ); and I am opening three new threads in this Science Folder, beginning with this thread on "Modelling the Anthropocene", as well as two other threads entitled: "Anthropogenic Existential Risks" (here: http://forum.arctic-sea-ice.net/index.php/topic,1307.0.html ) and "Adapting to the Anthropocene" (here: http://forum.arctic-sea-ice.net/index.php/topic,1308.0.html ). 
This new "Modelling the Anthropocene" thread expands beyond the hard physical science's examination of the Anthropocene, to embrace what the Germans call Geisteswissenschaften, or "human sciences"; within the rigorous, reasoned framework of coupled socioeconomic & climate change models.  This thread was inspired by the new Shared Socioeconomic Pathways (SSPs) currently being developed within the IPCC's framework to interact with the Recommended Concentration Pathways (RCPs).  However, I plan to expand beyond the IPCC framework to discuss such topics as: information technology, social science, economic theory, political science, palaeoenvironmental sciences, historiography, etc. all of which help us to understand the past (also see the "Defining the Anthropocene" thread), and to model the future, Anthropocene Era. 
To put the Anthropocene into perspective, the linked article by Joe Romm, points out that in 1995 Richard Leaky warned that homo sapiens is now the greatest agent for global catastrophe and is the most likely cause of the ongoing Holocene Extinction (The Sixth Extinction), which, puts the human species at risk of extinction (also see the "Existential Risk for Mankind" thread).
http://thinkprogress.org/climate/2015/06/01/3653348/sixth-extinction/
Extract: "“Homo sapiens is poised to become the greatest catastrophic agent since a giant asteroid collided with the Earth 65,000,000 years ago, wiping out half the world’s species in a geological instant.” So wrote anthropologist Richard Leakey in his 1995 book, “The Sixth Extinction: Patterns of Life and the Future of Humankind.”
Because of the vital dependence we have on the “ecosystem services” provided by the rest of nature, Leakey warned, “unrestrained, Homo sapiens might not only be the agent of the sixth extinction, but also risks being one of its victims.”"
To add prospective to the risks that mankind is taking that it might fall victim to "The Sixth Extinction", I provide the first attached image from the World Wildlife Fund that shows that Homo sapiens already use the equivalent of 1.5 Earths to support our consumption.

(see the first attached image)

For further perspective on why such an interdisciplinary (Geisteswissenschaften) consideration of the Anthropocene is merited, I provide the following link & extracts from the Slate article by Brad Allenby and Daniel Sarewitz (January 2015), "There’s No Place Like Home: Science, information, and politics in the Anthropocene", or: "Toto, we’re not in an era of simple scientific experimentation anymore."

http://www.slate.com/articles/technology/future_tense/2015/01/science_information_and_politics_in_the_anthropocene_or_the_age_of_humans.html

Extract: "First: Science ain’t what it used to be. Our ideal of science is of a highly structured activity for establishing cause-and-effect relationships that can be tested in the field and the laboratory. Now the focus is increasingly on computational models and scenarios aimed at exploring complex phenomena (such as climate change) that unfold on scales from the global to the molecular. Second: Information, which used to be scarce and closely guarded, is now everywhere, accessible to everyone. Once, the Catholic Church had a lock on what counted as knowledge and its interpretation. Then scientists took over. Today no individual or institution can ever have a monopoly on knowledge or expertise. Third: Therefore, the boundary between authoritative knowledge on one hand, and the subjective worlds of policy, ethics, and even religion on the other, grows increasingly fuzzy and meaningless. 
Taken individually, any of these changes would be a significant challenge to our current models of rational policymaking based on scientific principles; as a whole, they signal the most profound shift in social and cultural understanding of the role of science since the Scientific Revolution and the early Enlightenment, with its emphasis on formal knowledge as a basis for solving problems.

...

No one can replicate global environmental conditions in such a way as to experimentally test climate change. For such complex systems, the best we can do is create complicated computer models. But creating a model necessarily involves generating a set of rules that determines what we include in the model and what we exclude. And any set of rules that enables us to model a complex system that is coherent necessarily gives us a model that is partial and arbitrary—hence the common refrain that “all models are wrong, but some are useful.” We can use the model to generate multiple scenarios of the future that are consistent with scientific understanding, but we cannot have the underlying system itself. The complexity of the Anthropocene—in which, for example, climate change is an emergent phenomenon of 300 years of industrialism—is not subject to the sort of verifiable and predictive understanding that characterized science of the sort that Copernicus, Newton, or even Einstein practiced.
….
Does anyone out there think that radically transforming the global energy system will be easier and more predictable than turning Iraq into a democracy? Or that the evidence for doing so is more compelling than the evidence in favor of eliminating Saddam Hussein? Remember, in the Anthropocene, everything is more complicated. Our computer models can give us a thousand scenarios of how the climate may change. But remember that global warming is an unintended consequence of 300 years of industrialism—why would we think that equally momentous unintended consequences would not accompany the enormous social changes pursued in our effort to control the future behavior of the climate?
There is indeed a cruel dilemma here: In order for the science to matter, it must be heard; in order to be heard, it must be translated into catastrophic visions and simplistic policy formulations that are literally absurd abstractions of the complexity that we inhabit. Thus, the third condition of the Anthropocene: Science moves from being a mutually accepted foundation for debating action in the world to being the tool of one or another group of partisans, wielded in the settings of politics as if it were as clear and inescapable as the equations that Newton used to describe falling objects. The necessary oversimplification, urgent appeal to fear and insecurity, insistence on predictive certainty, and direct linkage to an explicit social agenda that would create huge new groups of winners and losers (and is thus inherently divisive) obliterate the boundary between science and politics.
What we will need above all to manage complexity in the Anthropocene is humility all around. We are not in Kansas anymore, where things are simple, the truth is clear, and we know what we know. Everything really is connected to everything else now, and the biggest mistake we can make is to focus too narrowly on one thing or one way of doing things. That’s the most important lesson of the abject failure of climate change policy and politics, and it’s one that we must learn if we are to effectively confront the new world that we have and will continue to create. Climate change is not a problem of our old way of doing things—it’s a symptom of our new condition."

For the end of this first post in this "Modelling the Anthropocene" thread, I note that the second attached image illustrates how risk is the product of probability (frequency) times (X) consequences (magnitude); therefore the greatest risk to society lays well to the right of the most probable climate change scenario.  I note that the scientific consensus probability density function, PDF, for global warming may likely skew to the right as: (a) we continue on an unsustainably high pathway for anthropogenic radiative forcing and (b) we learn more about the probabilities of high climate sensitivity.  Lastly, I note that the scientific consensus slope of the consequence curve may likely become steeper, particularly as more scientists acknowledge the true risks of abrupt sea level rise, ASLR.
 


15
Glaciers / Canadian Glaciers
« on: April 06, 2015, 11:00:22 PM »
The linked articles discuss projections that Alberta and BC will lose between 60 and 80% of the volume of their glaciers, as compared to 2005, by 2100.

http://www.9news.com.au/world/2015/04/07/01/49/canadian-glaciers-to-shrink-by-70-percent-by-2100

http://www.cbc.ca/news/technology/how-western-canada-glaciers-will-melt-away-1.3022242

16
Policy and solutions / Legal Approach to Climate Change Resolutions
« on: March 30, 2015, 11:08:14 PM »
The linked article & website (with free pdfs) discuss the Oslo principles legal approach to internalizing the externalities associated with climate change:

http://www.theguardian.com/commentisfree/2015/mar/30/climate-change-paris-talks-oslo-principles-legal-obligations

http://www.yale.edu/macmillan/globaljustice/news.html#oslo2015

http://www.yale.edu/macmillan/globaljustice/Oslo%20Principles.pdf

http://www.yale.edu/macmillan/globaljustice/Oslo%20Principles%20Commentary.pdf

Extract: "The Oslo Principles on Global Climate Change Obligations Launched by Expert Group Including GJP Director Thomas Pogge

It may seem that, in the absence of explicit treaties, states have no legal obligations to curb their greenhouse gas emissions. Yet, if emissions continue on their present trajectory, the harms they cause will reach catastrophic proportions, putting the human rights of billions of people in jeopardy. International human rights law is legally binding on states, which are, therefore, not free to continue business as usual. But how much do human rights and other sources of law, in particular tort law, require each state to do to reduce emissions, even in the absence of a specific treaty? A group of legal experts from around the world has answered this question, producing a set of Principles, setting out existing obligations regarding the climate, along with a detailed legal Commentary. These documents may help judges decide whether particular governments are in compliance with their legal obligations to address climate change. The principles may also serve many other purposes; for example, they may strengthen the bargaining position of poor countries by pointing to far-reaching obligations of wealthy countries."

The following quote cites the legal requirement for the application of the "Precautionary Principle":

"Precautionary Principle: There is clear and convincing evidence that the greenhouse gas
(GHG) emissions produced by human activity are causing significant changes to the climate and that these changes pose grave risks of irreversible harm to humanity, including present and future generations, to the environment, including other living species and the entire natural habitat, and to the global economy.

a. The Precautionary Principle requires that:
1) GHG emissions be reduced to the extent and at a pace necessary to protect against the threats of climate change that can still be avoided; and
2) the level of reductions of GHG emissions required to achieve this, should be based on any credible and realistic worst-case scenario accepted by a substantial number of eminent climate change experts.
b. The measures required by the Precautionary Principle should be adopted without regard to the cost, unless that cost is completely disproportionate to the reduction in emissions that will be brought about by expending it."

17
Glaciers / Icelandic Glaciers
« on: January 30, 2015, 05:21:43 PM »
The linked reference provides direct measurements of the vertical uplift acceleration of Icelandic crust that can only be accounted for by an associated acceleration of the rate of ice mass loss from Iceland:

Kathleen Compton, Richard A. Bennett and Sigrun Hreinsdóttir, (2015), "Climate driven vertical acceleration of Icelandic crust measured by CGPS geodesy", Geophysical Research Letters, DOI: 10.1002/2014GL062446

http://onlinelibrary.wiley.com/doi/10.1002/2014GL062446/abstract

Abstract
"Earth's present-day response to enhanced glacial melting resulting from climate change can be measured using Global Positioning System (GPS) technology. We present data from 62 continuously operating GPS instruments in Iceland. Statistically significant upward velocity and accelerations are recorded at 27 GPS stations, predominantly located in the Central Highlands region of Iceland, where present-day thinning of the Iceland ice caps results in velocities of more than 30 mm/yr and uplift accelerations of 1-2 mm/yr2. We use our acceleration estimates to back-calculate to a time of zero velocity, which coincides with the initiation of ice loss in Iceland from ice mass balance calculations and Arctic warming trends. We show, through a simple inversion, a direct relationship between ice mass balance measurements and vertical position and show that accelerated unloading is required to reproduce uplift observations for a simple elastic layer over viscoelastic half-space model."

18
Consequences / Climate Stress Promotes Militancy
« on: January 28, 2015, 04:11:29 PM »
All military planners recognize climate change as a stress riser for increasing global militancy (whether terrorists or rebels), e.g. it is generally recognized that much of the "Arab Spring" was linked to crop failures associated with climate change.  The linked article discusses how similar climate change stresses are now contributing to militancy of the poor in the Kashmir.

http://www.trust.org/item/20150126155123-vgut0/

Those who say that national security is a higher priority than fighting climate change should stop and realize that fighting climate change is probably the best way to help maintain national security.

19
Permafrost / Tibetan Permafrost Degradation
« on: January 26, 2015, 10:39:48 PM »
The Tibetan Mountains and Plateau is sometimes called third pole, and per the linked Glacier Hub article, permafrost degradation is making a significant contribution to alpine lake expansion in the Himalayas; which will likely increase both CO₂ and CH4 emissions:

http://glacierhub.org/2015/01/14/permafrost-melt-poses-a-greater-threat-than-glacial-melt-in-the-tibetan-plateau/

Extract: "According to a recent study published in the journal Public Library of Science, glacial melt is taking a backseat in the Himalayas to permafrost melt as a central driver of alpine lake expansion and related environmental hazards. This finding is of great importance to policy-makers and communities, who must prepare for flooding and other hazards which can be caused by the expansion of high-altitude lakes."

See also:

http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0111890#s2

20
Policy and solutions / Carbon Fee & Dividend Plan
« on: November 19, 2014, 08:40:16 PM »
The link discusses a new bill introduced in the US Senate for a carbon fee and dividend plan that might garner bi-partisan support (see extract below):

http://thinkprogress.org/climate/2014/11/19/3594242/sheldon-whitehouse-carbon-tax/

Extract: "According to details Whitehouse’s office released to reporters, the bill would impose a fee on all carbon emissions (and other greenhouse gas emissions) beginning in 2015. It would start at $42 per metric ton, and then increase by two percent annually in real terms. The fee would fall on all coal, oil, and natural gas that’s either produced in the United States or imported, and it would cover large emitters from non-fossil-fuel sources as well.
This sort of proposal is also commonly called a “carbon tax,” though politicians tend to avoid that term for obvious reasons. But the idea has wide support from commentators, economists, policymakers, and interest groups across both the left and right, because it’s seen as the most efficient and least intrusive way to cut greenhouse gas emissions. In his speech Wednesday, Whitehouse pointed to this support and previous proposals to put a price on emissions that “were market-based, revenue-neutral tools, aligned with Republican free-market values.”
“We simply need conscientious Republicans and Democrats to work together, in good faith, on a platform of fact and commons sense.”"

21
Glaciers / The Randolph Glacier Inventory, RGI
« on: September 13, 2014, 05:43:04 PM »
The linked reference (with an open access pdf) discusses the Randolph Glacier Inventory (RGI), which is the most complete collection of digital outlines of glaciers around the world:

Pfeffer, W. Tad; Arendt, Anthony A.; Bliss, Andrew; Bolch, Tobias; Cogley, J. Graham; Gardner, Alex S.; Hagen, Jon-Ove; Hock, Regine; Kaser, Georg; Kienholz, Christian; Miles, Evan S.; Moholdt, Geir; Mölg, Nico; Paul, Frank; Radić, Valentina; Rastner, Philipp; Raup, Bruce H.; Rich, Justin; Sharp, Martin J. (20140, "The Randolph Glacier Inventory: a globally complete inventory of glaciers", Journal of Glaciology, Volume 60, Number 221, June 2014, pp. 537-552(16)


http://www.ingentaconnect.com/content/igsoc/jog/2014/00000060/00000221/art00012


Abstract: "The Randolph Glacier Inventory (RGI) is a globally complete collection of digital outlines of glaciers, excluding the ice sheets, developed to meet the needs of the Fifth Assessment of the Intergovernmental Panel on Climate Change for estimates of past and future mass balance. The RGI was created with limited resources in a short period. Priority was given to completeness of coverage, but a limited, uniform set of attributes is attached to each of the ∼198 000 glaciers in its latest version, 3.2. Satellite imagery from 1999–2010 provided most of the outlines. Their total extent is estimated as 726 800±34 000 km2. The uncertainty, about ±5%, is derived from careful single-glacier and basin-scale uncertainty estimates and comparisons with inventories that were not sources for the RGI. The main contributors to uncertainty are probably misinterpretation of seasonal snow cover and debris cover. These errors appear not to be normally distributed, and quantifying them reliably is an unsolved problem. Combined with digital elevation models, the RGI glacier outlines yield hypsometries that can be combined with atmospheric data or model outputs for analysis of the impacts of climatic change on glaciers. The RGI has already proved its value in the generation of significantly improved aggregate estimates of glacier mass changes and total volume, and thus actual and potential contributions to sea-level rise."

22
Antarctica / Antarctica Surface Imagining
« on: August 21, 2014, 04:30:45 PM »
Due to a technical glitch, I cannot get into the "Mosaic" folder therefore, I will repost those links and add more information:

In the "Mosaic" folder, posted some similar to:

"A newly released image of Antarctica offers the most complete, detailed view of the continent since 1997. The map is a mosaic of more than 3,150 individual, high-resolution readings, taken in the Southern Hemisphere's autumn of 2008, and tiled together into a coast-to-coast view of the entire continent with its coastal waters (see the following links and the first attached image of the PIG/Thwaites area):

https://www.polardata.ca/
https://www.polardata.ca/pdcsearch/

However, as indicated by the second attached image of the Thwaites area in April 2012, and in the third and fourth image of Thwaites both in April of 2014, there has been a remarked change in this area since 2008.  Therefore, the linked "Mosaic" should be used with caution.

23
Antarctica / New Mosaic of Antarctica Surface
« on: August 20, 2014, 10:26:46 PM »
A newly released image of Antarctica offers the most complete, detailed view of the continent since 1997. The map is a mosaic of more than 3,150 individual, high-resolution readings, taken in the Southern Hemisphere's autumn of 2008, and tiled together into a coast-to-coast view of the entire continent with its coastal waters (see the following links, and the attached figure of the Ronne Ice Shelf):

https://www.polardata.ca/
https://www.polardata.ca/pdcsearch/

See also:

http://www.popsci.com/article/science/antarctica-pole-coast-stunning-detail


[attachment deleted by admin]

24
Glaciers / New Zealand's Southern Alps, & Other SH & Tropical, Glaciers
« on: August 10, 2014, 01:01:10 PM »
The following link leads to a web article focused on the glacial volume loss (the first attached image shows the loss since 1977) from New Zealand's Southern Alps going back to the 1890's, with a comparison to the global glacial volume loss (see the second image):

http://www.businessspectator.com.au/article/2014/7/29/science-environment/nzs-southern-alps-have-lost-third-their-ice

Extracts: "A third of the permanent snow and ice of New Zealand’s Southern Alps has now disappeared, according to our new research based on National Institute of Water and Atmospheric Research aerial surveys.
Since 1977, the Southern Alps’ ice volume has shrunk by 18.4 km3 or 34%, and those ice losses have been accelerating rapidly in the past 15 years."

"Martin Hoelzle and associates at the World Glacier Monitoring Service have estimated estimate the 1890s extent of ice volume in New Zealand’s Southern Alps was 170 km3, compared to 36.1 km3 now. That disappearance of 75-80 per cent of Southern Alps ice is graphic evidence of the local effects of global warming."

Caption for the first image: "The Southern Alps’ total ice volume (solid line) and annual gains or losses (bars) from 1976 to 2014 in km3 of water equivalent, as calculated from the end-of-summer-snowline monitoring programme.”

Caption for the second image: "Global Glacier Thickness Change: This shows average annual and cumulative glacier thickness change of mountain glaciers of the world, measured in vertical metres, for the period 1961 to 2005. (Mark Dyurgerov, Institute of Arctic and Alpine Research, University of Colorado, Boulder, CC BY)"


25
Antarctica / Internal Layers of the Antarctic Ice Sheet
« on: August 01, 2014, 02:27:48 AM »
A-Team was kind enough to provide the following link to the British Antarctic Survey's repository of images of the internal layers of the Antarctic Ice Sheet:

http://www.antarctica.ac.uk/bas_research/data/access/res/data.php


The IceBridge program also provides survey data from Antarctica as well, some of which can be found at the following links:

http://nsidc.org/data/ilatm2
http://nsidc.org/data/icebridge/index.html

The internal structure of the WAIS will become increasingly important, particularly to the ASE marine glaciers, as the ice shelves are lost and the ice flow velocities increase this will accelerate the formation of crevasses in the ice streams (such as PIG and Thwaites) which possibly as early as 2050 may contribute to major calving events in the ASE marine glaciers forming a mélange in-front of the marine glaciers, very much as is currently occurring for Jakobshavn. 

A-Team, and others, are doing a fantastic job of documenting the kinematics of the ice movement (including flow, crevasses and calving) for Jakobshavn; all of which will provide valuable lessons for the ASE marine glaciers, particularly if surface meltwater starts to flow into the crevasses for Jakobshavn (this year or in the near future); which could occur in the ASE marine glaciers by mid-century.

Edit: For those who want a preview of what internal structure is for an ice sheet, I provide the attached image of striations from the British Antarctic Survey site.

26
Science / Southern Ocean Venting of CO2
« on: June 05, 2014, 03:16:06 PM »
As I think that the CO2 concentration over Antarctica that A4R identified in the Mauna Loa CO2 thread, deserves its own thread, I am opening this topic on Southern Ocean Venting of CO2, by showing the two attached images from the MetOp-1 satellite for June 4 2014 at 892mb (near the ocean surface) that indicates to me that the sea ice extent is beginning to influence the amount of CO2, as more CO2 is shown near the Amundsen Sea Embayment where the sea ice extent is relatively low; and 506mb indicating that at this elevation much of the CO2 has moved away from the coastline and has moved more over the middle of Antarctica.  I will slowly add more to this thread, when I have time, but for the moment this phenomena appears to me to be a legitimate positive feedback mechanism that with cause polar amplification in Antarctica due to GHG concentration with the geopotential height well over Antarctica (which will cause the circumpolar winds to blow harder that will cause more venting)

27
While insurance companies primarily look after their own profit, in so doing they are now changing their policies to account for forward looking non-stationary climate change models; which may force other policy makers to similarly face the consequences of climate change.  The following link leads to a Climate Progress article on just this topic:

http://thinkprogress.org/climate/2014/05/19/3439048/insurance-climate-class-action-flood/

28
Currently Louisiana's coastal areas are losing an average of about 55 sq miles a year of coastal area, and the Lower Mississippi River Delta has the highest relative sea level rise rates in the USA (due to high local rates of subsidence).

If anyone has any new ideas, or research papers, on how to help save Louisiana's delta/coastal areas from disappearing beneath the waves, I would like to hear them.

Best,
Abrupt SLR

29
Antarctica / The WAIS Workshop 2013
« on: December 16, 2013, 02:57:39 PM »
The following links are to all of the abstracts, and pdf's of the available session presentations, from the WAIS Workshop 2013.  As I do not have time to comment about all of these abstracts & presentations at the moment, I invite any interested parties to download and comment on any of these downloads either in this new folder, or in any of the other relevant folders.  As time permits, I will comment on the downloads that I think are of most interest:

Abstracts:
ftp://sidads.colorado.edu/pub/projects/waisworkshop/2013/abstracts

Session 1 (Whillians Ice Stream)
ftp://sidads.colorado.edu/pub/projects/waisworkshop/2013/presentations/session1/
Session 2
ftp://sidads.colorado.edu/pub/projects/waisworkshop/2013/presentations/session2/
Session 3
ftp://sidads.colorado.edu/pub/projects/waisworkshop/2013/presentations/session3/
Session 4
ftp://sidads.colorado.edu/pub/projects/waisworkshop/2013/presentations/session4/
Session 5
ftp://sidads.colorado.edu/pub/projects/waisworkshop/2013/presentations/session5/
Session 6
ftp://sidads.colorado.edu/pub/projects/waisworkshop/2013/presentations/session6/
Session 7
ftp://sidads.colorado.edu/pub/projects/waisworkshop/2013/presentations/session7/


30
Policy and solutions / Super Chimney Concept
« on: September 09, 2013, 08:05:06 PM »
The following links lead to descriptions of a potential solution to both greenhouse warming and to a possibly economic source of sustainable energy using a "Super Chimney" concept:


Super Chimney: The Global Warming Solution

http://www.superchimney.org/co2.html

31
Antarctica / Antarctic Interactions with, and Lessons from, Greenland
« on: August 17, 2013, 06:03:33 PM »
There are many Antarctic interactions with, and lessons to be learned from, Greenland that are not fully discussed in the Greenland folder, therefore, I am opening this new folder on this important topic.

In the "Surge" thread I raised the prospect that the large increase in Greenland's contribution to SLR in 2012 might have triggered a temporarily large outflow of subglacial meltwater from beneath the WAIS via a postulated increase in local sea level around West Antarctic (due to the fingerprint effect of ice mass loss from Greenland), temporarily lifting up the grounding lines of key West Antarctic glaciers, thereby temporarily breaking the seal and allowing the basal melt water to surge out (and to also temporarily increase ice flow velocity).  While the "Surge" thread does document small surges of the Thwaites, and Ferrigano, Ice Tongues; the subsequent published GRACE data indicated that at best there was only a very minor surge in WAIS ice mass loss in 2012. 

Nevertheless, the 2012 experience does not mean that the postulated interaction between Greenland and AIS mass loss many not be more significant in the next few decades, as not only is Greenland's surface ice mass loss projected to increase in the near future, but as indicated by the following article, which discusses dynamic ice mass loss for four key marine terminating Greenland glaciers; which are projected to accelerate sharply in the next few decades before slowing down through 2200.  Therefore, there is a reason likelihood that the projected temporary surge in Greenland ice mass loss in the coming decades could trigger an acceleration of ice mass loss from key glaciers in the AIS (particularly in the WAIS):


http://www.nature.com/nature/journal/v497/n7448/full/nature12068.html


Future sea-level rise from Greenland’s main outlet glaciers in a warming climate
by: Faezeh M. Nick, Andreas Vieli, Morten Langer Andersen, Ian Joughin, Antony Payne, Tamsin L. Edwards, Frank Pattyn & Roderik S. W. van de Wal; Nature; 497,235–238(09 May 2013)doi:10.1038/nature12068


"Over the past decade, ice loss from the Greenland Ice Sheet increased as a result of both increased surface melting and ice discharge to the ocean. The latter is controlled by the acceleration of ice flow and subsequent thinning of fast-flowing marine-terminating outlet glaciers. Quantifying the future dynamic contribution of such glaciers to sea-level rise (SLR) remains a major challenge because outlet glacier dynamics are poorly understood. Here we present a glacier flow model that includes a fully dynamic treatment of marine termini. We use this model to simulate behaviour of four major marine-terminating outlet glaciers, which collectively drain about 22 per cent of the Greenland Ice Sheet. Using atmospheric and oceanic forcing from a mid-range future warming scenario that predicts warming by 2.8 degrees Celsius by 2100, we project a contribution of 19 to 30 millimetres to SLR from these glaciers by 2200. This contribution is largely (80 per cent) dynamic in origin and is caused by several episodic retreats past overdeepenings in outlet glacier troughs. After initial increases, however, dynamic losses from these four outlets remain relatively constant and contribute to SLR individually at rates of about 0.01 to 0.06 millimetres per year. These rates correspond to ice fluxes that are less than twice those of the late 1990s, well below previous upper bounds. For a more extreme future warming scenario (warming by 4.5 degrees Celsius by 2100), the projected losses increase by more than 50 per cent, producing a cumulative SLR of 29 to 49 millimetres by 2200."



This hypothesis is further supported by the recent finding (see the following reference) that the lithosphere below Greenland is thinner than previously thought; and therefore, one can expect that ice mass loss from Greenland will be faster than previously estimated (including faster than projected by the first article cited in this post):

http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo1898.html

Petrunin, A. G., Rogozhina, I., Vaughan, A. P. M., Kukkonen, I. T., Kaban, M. K., Koulakov, I. & Thomas, M., Heat flux variations beneath central Greenland’s ice due to anomalously thin lithosphere, Advance Online Publication, Nature Geoscience, 11. 08. 2013, http://dx.doi.org/10.1038/ngeo1898)



"Greenland ice is melting - even from below: Heat flow from the mantle contributes to the ice melt.  Modeled basal ice temperatures of the present-day Greenland Ice Shield across the Summit region, GRIP and GISP2 indicate borehole locations.
 
07.08.2013 | Potsdam: The Greenland ice sheet is melting from below, caused by a high heat flow from the mantle into the lithosphere. This influence is very variable spatially and has its origin in an exceptionally thin lithosphere. Consequently, there is an increased heat flow from the mantle and a complex interplay between this geothermal heating and the Greenland ice sheet. The international research initiative IceGeoHeat led by the GFZ German Research Centre for Geosciences establishes in the current online issue of Nature Geosciences (Vol 6, August 11, 2013) that this effect cannot be neglected when modeling the ice sheet as part of a climate study.

The continental ice sheets play a central role in climate. Interactions and feedback processes between ice and temperature rise are complex and still a current research topic. The Greenland ice sheet loses about 227 gigatonnes of ice per year and contributes about 0.7 millimeters to the currently observed mean sea level change of about 3 mm per year. Existing model calculations, however, were based on a consideration of the ice cap and considered the effect of the lithosphere, i.e. the earth's crust and upper mantle, too simplistic and primarily mechanical: the ice presses the crust down due to its weight. GFZ scientists Alexey Petrunin and Irina Rogozhina have now coupled an ice/climate model with a thermo-mechanical model for the Greenland lithosphere. "We have run the model over a simulated period of three million years, and taken into account measurements from ice cores and independent magnetic and seismic data", says Petrunin. "Our model calculations are in good agreement with the measurements. Both the thickness of the ice sheet as well as the temperature at its base are depicted very accurately. "

The model can even explain the difference in temperature measured at two adjacent drill holes: the thickness of the Greenland lithosphere and thus the geothermal heat flow varies greatly in narrow confines.
What does this mean for climate modeling? "The temperature at the base of the ice, and therefore the current dynamics of the Greenland ice sheet is the result of the interaction between the heat flow from the earth's interior and the temperature changes associated with glacial cycles," explains corresponding author Irina Rogozhina (GFZ) who initiated IceGeoHeat. "We found areas where the ice melts at the base next to other areas where the base is extremely cold."

The current climate is influenced by processes that go far back into the history of Earth: the Greenland lithosphere is 2.8 to 1.7 billion years old and is only about 70 to 80 kilometers thick under Central Greenland. It remains to be explored why it is so exceptionally thin. It turns out, however, that the coupling of models of ice dynamics with thermo-mechanical models of the solid earth allows a more accurate view of the processes that are melting the Greenland ice."





32
Antarctica / Trends for the Southern Ocean
« on: June 27, 2013, 05:01:59 PM »

Following-up on one of Sidd's suggestion, I am opening this thread in order to break-out future discussions of trends in the Southern Ocean with regard to such topics as: Ocean Heat Content, OHC;  overturning, upwelling, CO₂ absorption, salinity, circulation patterns, eddies, etc.

I begin with the following paper (and link); which, indicates that the Southern Ocean continues to act as a sink for absorbing CO₂, but that this absorption could stabilize in the near future, with continuing CO₂ emissions:

Sea–air CO2 fluxes in the Southern Ocean for the period 1990–2009
by: A. Lenton et al, 2013;
Biogeosciences, 10, 4037–4054, 2013
www.biogeosciences.net/10/4037/2013/; doi:10.5194/bg-10-4037-2013

http://www.biogeosciences.net/10/4037/2013/bg-10-4037-2013.pdf


33
Antarctica / Subglacial Lake and Meltwater Drainage Systems
« on: June 26, 2013, 08:48:46 PM »
The accompanying figures are from, and they show the extensive subglacial lake and meltwater drainage systems in Antarctica (with increasing warming [due to: surface, ocean, basal, basal friction, albedo, surface melting] these systems should be come more extensive and important in the future):

Predicting subglacial lakes and meltwater drainage pathways beneath the Antarctic and Greenland ice sheets
by: S. J. Livingstone, C. D. Clark, and J. Woodward
The Cryosphere Discuss., 7, 1177–1213, 2013, www.the-cryosphere-discuss.net/7/1177/2013/, doi:10.5194/tcd-7-1177-2013

The caption for the first image is: "In (B), the blue colour illustrates regions below the pressure melting point. This is used as a simple mask to remove all subglacial lakes that fall within the cold-bedded zones. Note, the subglacial drainage network is still treated as though the bed was wholly warm based."

The second image is a close-up of an area taken from the first image, but focused on the WAIS area, and which shows subglacial lakes in the Thwaites Drainage basin.

The caption for the third image is:  "(B) the fraction of the grounded ice-sheet bed occupied by subglacial lakes vs ice-sheet area, with both the Antarctic and Greenland subglacial lake data plotted.

34
Antarctica / Antarctic Tectonics
« on: June 23, 2013, 08:53:50 PM »
Most of what I have posted focuses on ice and the risk of ice mass loss contributing to abrupt sea level rise, ASLR; however, some of my posts have made it clear that any significant loss of ice mass will engage the underlying continental crust/upper mantle (lithosphere/asthenosphere); for reasons including: Glacial Isostatic Adjustment (GIA); volcanism; seismicity; rift valleys; and bed characteristics.  Therefore, I have opened this new thread to briefly examine selected aspects of the relatively unique/peculiar Antarctic tectonics/geology.

To begin this thread I start with some aspects of the Gondwana breakup, with the attached four images coming from Sears 2006:

The first image shows the southern supercontinent Gondwana about 183million year ago at the point of the initial breakup of the supercontinent.

The second image highlights the Euler geometry of hexagons and pentagons bounded by the supercontinent rupture lines that define the lines of minimum energy required to break apart the supercontinent.

The third image shows the correspondence of tectonic hotspots from the time of breakup to the modern geometry.

The fourth image shows the direction of migration of other tectonic plates from Antarctica, together with the modern seafloor, plate margins and historical hotspot locations.

35
Antarctica / Discussion of the Antarctic Peninsula
« on: May 20, 2013, 03:45:54 PM »
So far I have only discussed the Antarctic Peninsula in passing; however, as it has one of the fastest rates of surface warming of any location on Earth, it will likely see significant ice degradation even before the WAIS, and thus merits a closer examination.  I will begin by looking at the Antarctic Peninsula, AP, ice shelves, focused on the Larsen C ice shelf (which could collapse rapidly any year now).  The following three recent articles from the internet indicate that a combination of crevasses, subglacial melting and increased surface melting put these ice shelves (an particularly the Larsen C ice shelf) in increasingly worst shape:

The first article is from:
http://cires.colorado.edu/steffen/larsenC/

"Significant glaciological and ecological changes are occurring along the Antarctic Peninsula in response to climate warming that is proceeding at 6 times the global average rate (King et al., 1994; Vaughn et al., 2003). Floating ice shelves, the extension of outlet glaciers, are responding rapidly and have lost ~28,000 km2 in the last 50 years, including the catastrophic collapse of Larsen A in 1995, Larsen B in 2002 and the Wilkins ice shelf in 2008-09 (Cook and Vaughn, 2009). Following ice shelf collapse, the outlet glaciers that nourished the ice shelves have accelerated and thinned in response to the removal of the backstress that the ice shelf provided. In the case of Larsen B, an additional -27 km3 yr-1 of ice was discharged due to the removal of this backstress (Rignot et al., 2004).
The significance of ice shelf collapse and subsequent acceleration of outlet glaciers is amplified by the fact that 40% of the Antarctic continent is ringed in ice shelves and that 80% of ice flux from the continent passes through these gates (Drewy, 1982; Jacobs et al., 1992). The climatic regime of the Antarctic Peninsula and the latitudinal changes in ice shelf stability provide a unique opportunity to study the full spectrum of ice shelf stability—from recently collapsed to fully stable—in order to gain a broader understanding of the climatic conditions and physical processes that result in ice shelf stability and instability. This understanding is essential to future estimates of ice sheet contributions to global sea level rise.
This project focuses on Larsen C, the largest remaining ice shelf on the Antarctic Peninsula. Larsen C has a surface area of ~55,000 km2 and is composed of 12 major flow units fed by outlet glaciers (Glasser et al., 2009). Average ice thickness is ~300 m but ranges from ~500 m near the grounding line to ~250 m near the ice edge (Griggs and Bamber, 2009). "


The second abstract is from:
Basal crevasses on the Larsen C Ice Shelf, Antarctica: Implications for meltwater ponding and hydrofracture, By McGrath et al 2012, GEOPHYSICAL RESEARCH LETTERS, doi:10.1029/2012GL052413
"A key mechanism for the rapid collapse of both the Larsen A and B Ice Shelves was meltwater-driven crevasse propagation. Basal crevasses, large-scale structural features within ice shelves, may have contributed to this mechanism in three important ways: i) the shelf surface deforms due to modified buoyancy and gravitational forces above the basal crevasse, creating >10 m deep compressional surface depressions where meltwater can collect, ii) bending stresses from the modified shape drive surface crevassing, with crevasses reaching 40 m in width, on the flanks of the basal-crevasse-induced trough and iii) the ice thickness is substantially reduced, thereby minimizing the propagation distance before a full-thickness rift is created. We examine a basal crevasse (4.5 km in length, ~230 m in height), and the corresponding surface features, in the Cabinet Inlet sector of the Larsen C Ice Shelf using a combination of high-resolution (0.5 m) satellite imagery, kinematic GPS and in situ ground penetrating radar. We discuss how basal crevasses may have contributed to the break up of the Larsen B Ice Shelf by directly controlling the location of meltwater ponding and highlight the presence of similar features on the Amery and Getz Ice Shelves with high-resolution imagery."


The third abstract is from:
http://nora.nerc.ac.uk/501292/

Basal melt rates on Larsen-C Ice Shelf by Jenkins, Adrian; Shepherd, Andrew; Gourmelen, Noel. 2013
Abstract/Summary
During the past decade, the Larsen Ice Shelf has progressively thinned and two large sections have collapsed, catastrophically, leading to increased ice discharge into the oceans and a consequent rise in global sea level. If similar events are to occur at the remaining Larsen-C section, the fate of a tenfold greater ice reservoir hangs in the balance. Although the origin of the underlying instability has yet to be determined, only three processes can realistically be to blame; enhanced basal or surface melting, or accelerated flow. To quantify rates of basal ice melting, a phase sensitive radar was deployed on the Larsen-C Ice Shelf. The radar is a high-precision instrument that directly measures changes in thickness of the ice shelf, in contrast to indirect methods that infer basal melting from surface observation while assuming steady state. We established three radar sites on Larsen-C where time-series of satellite altimeter data are also available. The sites were revisited twice over the course of one year to measure the annual mean and summertime rates of basal melting. The annual mean measurements proved difficult to interpret because of a lack of reproducibility in the radar layer structure within the ice shelf over long periods of time. Measurements made within one summer field season proved more reliable, yielding melt rates of between 4 and 8 m yr-1 near the grounding line, near zero over the ice shelf interior and around 2 m yr-1 near the ice front. Such a spatial pattern of melting is consistent with models of the ocean circulation beneath the ice shelf, while the magnitude near the grounding line suggests that waters with temperatures above the surface freezing point reach the inner cavity at least intermittently. Temporal variability in the melt rate is a strong candidate for driving the observed thinning to the ice shelf, at least over its southern half."

36
Antarctica / Majestic Antarctic Images
« on: May 16, 2013, 11:24:38 PM »
A4R's postings in the "Weather" thread inspired me to open this new thread of majestic Antarctic images.  Feel free to post your favorite images and/or videos about the Antarctic; maybe they will inspire someone to try to preserve this natural wonder (and in the meantime save the world from a lot of sea level rise).

37
Antarctica / Glaciology Basics and Risks - Uncertainties
« on: May 16, 2013, 08:44:40 PM »
I am opening this new thread both to provide some discussion of glaciology basic concepts/terminology for basic readers, and also to create a forum to illustrate situations where traditional thinking on glaciology may result in imposing unnecessary risks/uncertainties on the global society with regard to abrupt sea level rise, ASLR.

First I provide the following definitions:

Mass balance is the change in the mass of a glacier or ice body, or part thereof, over a stated span of time.  The term mass budget is a synonym. The span of time is often a year or a season. A seasonal mass balance is nearly always either a winter balance or a summer balance. The (cumulative) mass balance, b, is the sum of accumulation, c, and ablation, a (the ablation
is defined here as negative). The symbol, b (for point balances) and B (for glacierwide balances)
has traditionally been used in studies of surface mass balance of valley glaciers.  Mass balance is often treated as a rate, b or B dot.

Accumulation
1. All processes that add to the mass of the glacier.
2. The mass gained by the operation of any of the processes of sense, expressed as a positive
number.
Components:
- Snow fall (usually the most important).
- Deposition of hoar (a layer of ice crystals, usually cup-shaped and facetted, formed by
vapor transfer (sublimation followed by deposition) within dry snow beneath the snow
surface), freezing rain, solid precipitation in forms other than snow (re-sublimation
composes 5-10% of the accumulation on Ross Ice Shelf, Antarctica).
- Gain of windborne blowing snow and drifting snow
- Avalanching
- Basal freeze-on (usually beneath floating ice)
- Internal accumulation.
Note: Unless it freezes, rainfall does not constitute accumulation, and nor does the addition of
debris by avalanching, ashfall or similar processes.

Ablation
1. All processes that reduce the mass of the glacier.
2. The mass lost by the operation of any of the processes of sense, expressed as a negative
number.
Components:
- Melting (usually the most important on land-based glaciers. Melt water that re-freezes
onto another part of the glacier is not referred to as ablation).
- Calving (or, when the glacier nourishes an ice shelf, ice discharge across the grounding
line): Calving is iceberg discharge into seas or lakes; important, for example, in
Greenland and Antarctica, where approximately 50% and 90%, respectively, of all
ablation occurs via calving.
- Loss of windborne blowing snow and drifting snow
- Avalanching
- Sublimation (important, for example, in dry climates, and on blue-ice zones in Antarctica; is a function of vapor pressure)
Note the difference between a) precipitation (includes solid precipitation and rain) and surface accumulation (does not include rain).  Note, that in contrast to what is natural in dynamic glaciology and glacial geomorphology, for mass-balance purposes the glacier consists only of frozen water. Sediment carried by the glacier is deemed to be outside the glacier. Meltwater in transit or in storage, for example in supraglacial lakes or subglacial cavities, is also regarded as being outside the glacier.
b) Meltwater and Meltwater runoff (A portion of melt may refreeze; the latter refers to the
meltwater that does not refreeze)
c) Meltwater runoff and Runoff (the latter includes rain or any other source of water other than
meltwater.
d) Accumulation and Net accumulation (the latter is a balance, i.e. accumulation plus ablation.
It is identical to the mass balance in case the balance is positive. It equals zero in case the
balance is negative).

Next, I briefly discuss the attached image showing some basic glaciological concepts for a marine terminating glacier contribution ice mass to SLR.  This figure shows how mass balance "dot b" integrated over area "A" gives the input of ice mass "Q" into the upstream end of the glacial flow (also "Q" but for U integrated over the glacier's cross section), thus causing a gravity force that is partially resisted by basal (and side) friction (and an allowance for energy dissipation from internal work of deforming and internal melting of the glacial ice as it flows down hill).  The value of Qcalving is intended in this image to represent the discharge (ice volume per unit time) of ice mass contributing to SLR associated with glacial flow velocity "U".  However, for simplicity this figure does not illustrate ice mass contribution to SLR from: (a) ice surface melting and run-off; (b) basal meltwater discharge, and (c) grounding line retreat due to advective melting of the grounded ice.

38
Antarctica / Antarctic Weather and Meteorology
« on: May 14, 2013, 05:05:21 PM »
I am opening this new thread, not because I know a lot about Antarctic Weather and Meteorology, but because this is a critical topic and needs to be covered, particularly with regard to: ice surface melting temperatures, precipitation, wind patterns, storm action and regional oscillation weather patterns .  I can recommend the two following websites for monitoring Antarctic weather forecasts:
http://www.weather-forecast.com/maps/Antarctica
http://www.weather-forecast.com/maps/Antarctica

As an example of the importance of weather related ice surface melting temperatures, I provide the attached image of Antarctic areas subjected to surface ice melting in January 2005, and the following summary (from June 2012) is from the Norwegian Polar Institute website, which emphasizes the important role that such surface melt water has on ice mass loss from both ice shelves and grounded ice:

Sun-heated surface water contributes towards melting under ice shelves in Dronning Maud Land.

"About half of the melting of the Antarctic ice cap occurs on the underside of ice shelves – floating glaciers several hundred metres thick. Research recently published in Geophysical Research Letters shows that surface water heated by the sun is a crucial source of heat, and contributes to melting in the sea under the Fimbul Ice Shelf in Dronning Maud Land. It was previously known that hot water from the depths also causes the bottom of the ice shelf to melt.
– “It came as a surprise to us that warm water from the surface plays such an important role for ice melting in Dronning Maud Land,” says the article’s first author, researcher Tore Hattermann from the Norwegian Polar Institute.
 
Tore Hattermann has been participating in field work at Fimbulisen for three years in a row; he and his colleagues have analysed two years’ worth of data collected from three rigs that were deployed in 2010. When glaciers in Antarctica melt, the sea level rises all around the globe, including the Arctic. Hattermann emphasises that knowledge about the melting of the ice cap is crucial for understanding and predicting changes in sea level.

– “If we wish to understand what will happen to the ice in Antarctica and the future climate, we must understand the interactions between the ongoing changes in the atmosphere and the melting that occurs hundreds of metres below the sea surface,” says Hattermann.

To date, very few measurements of sea temperature have been done under the Antarctic ice shelves. In some places in West Antarctica, there is extremely rapid melting owing to direct contact between the ice and warm water from the ocean depths. In East Antarctica, where the Fimbul Ice Shelf is located, the new measurements show that melting is limited because warm water is in contact with the ice only for part of the year.

The researchers surmise that the amount of warm water that comes in contact with the ice varies depending on the extent of sea ice and wind conditions along the coast of Dronning Maud Land. These new results provide important clues about the processes that control melting along the coast of Dronning Maud Land.

The study is part of the ICE-Fimbul Ice Shelf project and is being carried out by researchers from the Norwegian Polar Institute in collaboration with other research institutes from Norway and abroad."

39
Antarctica / Liability and SLR Contribution from the AIS
« on: May 10, 2013, 05:01:54 PM »
The question of liability (legal or otherwise) associated with sea level rise (SLR) contributions from the Antarctic Ice Sheet (AIS) is not a new topic.  However, I believe that the nature of the 'Fat-Tailed" probability density function (PDF) for this risk is so different from the historical risk PDFs that our legal, societal, and infrastructure design standards have evolved to address; that this question merits a new thread devoted to re-examining some of the basic assumptions related to this matter.

For example, in the 1990's several US states (including California) filed a lawsuit against the Environmental Protection Agency, EPA, demanding the CO2 be better regulated; and as part of that lawsuit James Hansen testified about the risks (PDF) associated with abrupt SLR from the potential collapse of both: the Greenland Ice Sheet, GIS, and the AIS.  However, his testimony was heavily attacked/discredited by the defense attorneys when the pointed out that Hansen was not a glaciologist and when the prosecution could not find a single glaciologist who would support Hansen's testimony.  Subsequently, the states of California, Oregon and Washington retained the US National Research Council, NRC, to evaluate the risk of SLR to the US West Coast (including an evaluation of the risk of abrupt SLR), and in 2012 the NRC (which included Tad Pfeffer on the board) issued their findings, which discounted the risk of abrupt SLR, in a manner similar to that presented in the leaked draft of the IPCC's AR5 (of which Tad Pfeffer has contributed).

Now I would like to quote from Al Gore's new book: The Future Six Drivers of Global Change, Random House, 2013, from page 320:

"Most legal systems in the world make it a criminal offense, as well as a civil offense, for anyone to knowingly misrepresent material facts for the purpose of self-enrichment at the expense of others who rely on the false representations and suffer harm or damage as a result.  If the misrepresentation is merely negligent, it can still be a legal offense.  If the false statements are reckless and if the harm suffered by those induced to rely on the false statements is grave, the offense is more serious still.  The most common legal standard for determining whether or not the person (or corporation) misrepresenting the material facts did so "knowingly" is not "beyond a reasonable doubt," but rather the "preponderance of the evidence.""

Now I would like to point out that while individual scientist many not be subject to civil liability for providing their expert opinions, government agencies such as the NRC who have been contracted by states, such as California, Oregon, and Washington, to provide SLR guidance that the states are relying on for their regulation of at risk infrastructure; are such subject to such civil liability prosecution if it can be shown that the administration of the agency should have provided better warnings of risks not addressed in their contracted work product (such as the NRC 2012 SLR guidance document).

Clearly Hansen has never backed down from his position regarding the risks of abrupt SLR, and indeed his has retired early from NASA (apparently due to administrative pressure that is not part of the scientific process); so that he can better prepare legal liability suit(s) against the federal government (apparently for negligence).

While this is a complex question, I believe that we have now entered the "Age of Consequences" so that there are now a number of parties that have standing in the courts due to damage that they have suffered due to the negligence of various agencies; and thus we will likely start to see better legal opinions on who is liable.  Also, due to the complexity of this question, in subsequent posts, I expect to discuss short-term liabilities associated with: (a) insurance, including the changing US National Flood Insurance Program, NFIP, and the associated changing US Federal Emergency Management Agency, FEMA, standards for insurability; and (b) changing flood design standards for infrastructure.

40
In April, 2013, the Japanese Ministry of Economy, Trade and Industry said a team aboard the scientific drilling ship Chikyu had started a trial extraction of gas from a layer of methane hydrates about 300 meters, or 1,000 feet, below the seabed. The ship has been drilling since January in an area of the Pacific about 1,000 meters deep and 80 kilometers, or 50 miles, south of the Atsumi Peninsula in central Japan.   With specialized equipment, the team drilled into and then lowered the pressure in the undersea methane hydrate reserve, causing the methane and ice to separate. It then piped the natural gas to the surface.  Other teams are pioneering other means of extracting methane from hydrates with the soil, both in the seafloor and in terrestial areas of the Arctic region.

This raises the question to me about what beneficial uses could be developed for methane recovered from Antarctic methane hydrates, primarily from beneath the ice sheets, but also possibly from the seafloor (see the Antarctic Methane Concentration thread).

For some basics, the first attached figure gives the pressure-temperature stability curves for methane, ethane, propane and iso-butane; while the second image shows the stability curves for various mixtures of methane and propane.  The first graph shows that methane hydrates are stable at basal meltwater temperatures in water depths deeper than about 350 m. 

Therefore, as my first example, if one could locate methane hydrates in the gateway of the Thwaites Glacier, then one could drill down and reduce the pressure until the hydrates in the sediment decompose and fill the drill pipe (like the Japanese), then the methane gas could be gradually introduced into solution into the basal meltwater beneath the Thwaites Glacier gateway (which is all below 350m).  This would stabilize the basal meltwater in this area and would increase basal friction and could possible stop the advective formation of subglacial cavities (if deployed correctly).  If one had a few high priority areas, then one could import propane to be mixed with the methane gas, to result in methane-propane hydrates that are stable at much shallower water depths.

41
I begin by posting the following article from Science (March 2013) by Carolyn Gramling, which indicates the newly identified risk that the Southern Ocean may start releasing CO2 into the atmosphere with increasing global warming, as well as the challenges for Regional Circulation Models, RCMs, to model this behavior:

Warming World Caused Southern Ocean to Exhale
The attached image shows the location of two sediment cores from the Ocean Drilling Program in the Southern Ocean reveal a million-year-long glacial-interglacial cycle of fluctuating ocean productivity and upwelling, correlating to ice-core atmospheric carbon dioxide records. Colors show average sea surface temperatures from January to March from 1978 to 2010.
Credit: S. L. Jaccard et al., Science (2013)
No land intersects the 60° circle of latitude south of Earth's equator. Instead, that parallel marks the northern limit of the Southern Ocean surrounding Antarctica. At this latitude, swift, prevailing westerly winds continually churn the waters as they circumnavigate the continent, earning the region the nickname "the screaming '60s".
But the Southern Ocean plays a more benign role in the global carbon budget: Its waters now take up about 50% of the atmospheric carbon dioxide emitted by human activities, thanks in large part to the so-called "biological pump." Phytoplankton, tiny photosynthesizing organisms that bloom in the nutrient-rich waters of the Southern Ocean, suck up carbon dioxide from the atmosphere. When the creatures die, they sink to the ocean floor, effectively sequestering that carbon for hundreds or even thousands of years. It also helps that carbon dioxide is more soluble in colder waters, and that the churning winds mix the waters at the surface, allowing the gases to penetrate the waters more easily.
There are signs, however, that the ocean's capacity to sequester atmospheric carbon dioxide has been decreasing over the past few decades, says climate scientist Samuel Jaccard of ETH Zurich in Switzerland. For one thing, the carbon doesn't stay sunk. Even as phytoplankton blooms sequester new carbon, the upwelling of deep, subsurface water currents in the region bring old, once-sequestered carbon back to the surface waters, allowing for exchange with the atmosphere. Meanwhile, the ozone hole has strengthened winds in the region, which may be hindering the carbon storage.
For clues to the future, climate scientists look to past glacial-interglacial cycles. Researchers have a record of atmospheric carbon dioxide stretching back millions of years thanks to ice cores from Antarctica, which contain trapped gas bubbles, snapshots of ancient air. But for the other half of the picture—what happened in the oceans during that time—there is only a relatively short record extending back about 20,000 years to the last glacial cycle. Ocean sediment records, which contain evidence of carbon and nutrients, are one way to reconstruct that history.
Previous ocean sediment records suggest that, as the world slipped into the last glacial period, less carbon overall reached the sediments of the Southern Ocean, coinciding with declining atmospheric carbon dioxide. During cold periods, increased sea-ice cover can keep gases trapped in the ocean—and the drier, dustier conditions bring much-needed iron to phytoplankton in the sub-Antarctic portion of the Southern Ocean, feeding blooms that gobble down carbon dioxide from the atmosphere.
What happens when the world moves into a warm, interglacial period isn't certain, but in 2009, a paper published in Science by researchers found that upwelling in the Southern Ocean increased as the last ice age waned, correlated to a rapid rise in atmospheric carbon dioxide.
Now, using two deep cores collected at two Ocean Drilling Program sites in the Southern Ocean, Jaccard and colleagues have reconstructed ocean records of productivity and vertical overturning reaching back a million years, through multiple glacial-interglacial cycles. This rapid increase in carbon dioxide as the world transitions from glacial to interglacial seems to be a pretty regular thing, they've found.
"There was relatively more carbon dioxide emitted from the deep ocean and released to the atmosphere as the climate warmed," Jaccard says. "The Southern Ocean sink was less effective."
As the world transitioned to glacial periods, on the other hand, atmospheric carbon dioxide decreased. This happened in two steps: First, in the Antarctic zone of the Southern Ocean, a reduction in wind-driven upwelling and vertical mixing brought less deep carbon to the surface. Then, about 50,000 years later, atmospheric carbon dioxide decreased again, the team reports online today in Science. This decrease, Jaccard says, is linked to blooms of phytoplankton in the sub-Antarctic Zone, slightly farther north, driven by an influx of iron carried by dusty winds.
The regularity of the glacial-interglacial signal is intriguing, and "it's a valid point to be making," says Robert Toggweiler of the National Oceanic and Atmospheric Administration's Geophysical Fluid Dynamics Laboratory in Princeton, New Jersey. But he questions how to apply it to the future, because modelers have trouble making models sophisticated enough to reproduce such a signal.
It's known that when ice sheets start to melt, cooling the air in that region, the winds over the Southern Ocean strengthen, Toggweiler says. "The question is how does that signal get to the Southern Ocean?" The ozone hole plays a role in the stronger winds, but so does increasing temperature. So far, no one has been successful at taking the cooling in the north and generating winds in the south that produce much of a carbon dioxide response. "In general, models have been spectacularly unsuccessful in replicating this sort of response we're seeing here," he says.

42
Antarctica / EAIS Contributions to SLR by 2100
« on: April 26, 2013, 05:57:05 PM »
I am opening this thread to discuss the possible East Antarctic Ice Sheet, EAIS, contributions to SLR by 2100.  While the EAIS is generally more stable than the WAIS the two accompanying figures make it clear that significant areas of East Antarctica have bed elevations below sea level and are thus possibly subject to accelerated ice mass loss due to possible interaction with ocean water.  In subsequent posts I plan to provide information regarding some of the less stable areas of the EAIS, including discussions of areas that could become activated if/when the WAIS collapses.

43
Antarctica / Glossary of Key Terms and Acronyms
« on: April 21, 2013, 08:03:33 PM »
Many technical terms and acronyms are used in my posts in this Antarctic folder; therefore, I have started this new thread with a brief Glossary of Key Terms and Acronyms.  Furthermore, I invite readers to submit posts with additional terms that merit definitions; which, I plan to provide on an as needed basis:

AABW - Antarctic Bottom Water

ACC - Antarctic Circumpolar Current, which advects a large volume water mass of warm water just below the surface layer known as Upper Circumpolar Deep Water (UCDW). This water mass supplies heat across the continental shelf. The heat from this water mass and its underlying Lower Circumpolar Deep Water (LCDW) travels across the continental shelf via deep canyons, serving as conduits to the coastline where it can reach the underside of the ice shelves/ice sheets, contributing to their melt and raising sea level.

AIS - Antarctic Ice Sheets.

albedo - How reflective a surface is. High albedo means that much of the incoming radiation is reflected (for example snow and ice); low albedo means that much of the incoming radiation is absorbed (for example water).

Albedo Flip - "Albedo flip" is a term that  describes the process by which a  former heat-reflecting ice surface will become a heat-absorbing body of water.

AR3, AR4, AR5 - IPCC Assessment Reports 3, 4 and 5, respectively.

Antarctic Bottom Water - The coldest and densest water mass in the global oceans. Formed in particular places on the Antarctic continental shelf such as Weddell Sea and Ross Sea when surface water cools and becomes more dense and so sinks to the ocean floor. Once formed it tends to flow northwards hugging the seafloor. It can be traced into many ocean basins, including parts of the North Atlantic Ocean.

Antarctic Circumpolar Trough - An atmospheric feature located between 60°S and 65°S. A zone of low pressure that causes variable winds moving from west to east and responsible for the "Screaming sixties" as known to seamen.

Antarctic Convergence (Polar Front) - A surface boundary where which the colder, north flowing Antarctic Surface Waters sink beneath warmer circulating waters. This marks a change in the oceans surface temperature and also chemical composition. North of the convergence, the area is known as the sub-Antarctic.

BAU - "Business as Usual"; as it relates to SLR, in a BAU scenario, no measures are taken to mitigate or arrest the conditions that cause global climate changes

calve - The formation of an iceberg from a glacier. Once the ice flowing from a glacier reaches a body of water it begins to float and may crack at the "hinge zone", once free of the glacier a piece of ice becomes an iceberg and the glacier has calved.

CDW - Circumpolar Deep Water (see ACC)

CL - Confidence Level

continental shelf - The region in the ocean around a continent between the shoreline and the continental slope. An area of shallow water where the depth is usually less than 200 meters (650 feet). In Antarctica however, the continental shelf averages 500 meters in depth (1640 feet)! The continental shelf has formed by slow deposition of sediment eroded from the continent and has a gentle slope (around 1°).

continental slope - Narrow, steep (3° to 6° slope) transition zone between the shallow shelf and the deep ocean floor.

Coriolis effect - moving objects appear to deflect from their anticipated straight-line course. Coriolis effect is a result of the rotation Earth (and an observer's position on it). Responsible for the fact that water spirals down a plug-hole rather than going straight and the direction is different in each hemisphere. Only at the equator does water go straight down.

crevasse - A deep, usually vertical, crack or split in a glacier, occurs as a result of the brittle ice flowing over a uneven surface beneath the ice. Crevasses can easily become covered by blown snow, even very wide ones. Great care must be taken when crossing ice and snow fields to avoid them.

cryosphere - That portion of Earth's surface that is permanently frozen through the year.

downwelling - In oceanography, the replacement of deep waters by surface waters moving down because of a change in temperature or more rarely salinity. Downwelling may bring waters rich in oxygen to the deeper parts of the ocean or lake.

draft - The distance below the water level (sea level) the bottom of an iceberg reaches. In some cases, icebergs are blown into shallow waters by storms and the bottom ploughs into the ocean causing the iceberg to get stuck. Draft also refers to how far below the water line the keel of a ship reaches and so determines how close into shore the ship can go.

East Wind Drift (Antarctic Coastal Current) - Westward flowing ocean surface current that flows anti-clockwise around Antarctica, driven by the polar easterlies.

easterlies - Winds that blow from the east. The polar easterlies blow close to the continent and help move the ocean surface currents known as the east wind drift.

EAIS - East Antarctic Ice Sheet

ENSO - El Nino Southern Oscillation

evaporation - Change in state from a liquid or a solid to a gas. Evaporation takes place most quickly in an arid or dry environment when there is little or no water vapor in the air. Antarctica is arid and solid ice can "evaporate" or turn into a gas, particularly if a (relatively) warm wind blows across a snow or ice field. The change from a solid directly to a gas is properly called sublimation - like the "smoke" you get when you open the freezer door.

extraordinary Katabatic wind - Katabatic wind that is particularly long-lasting (days to even weeks) and remains fairly constant in strength during that time.

fast ice - Sea ice that forms in situ along the coastline and remains attached.

firn - A transitional stage between snow and glacial ice, a type of snow that has survived a summer melting season and has become more compact than freshly falling snow.

fissure - A long, very deep, narrow opening, sometimes used instead of crevasse.

fjord (fiord) - A long, narrow, steep-walled, u-shaped coastal inlet. Fjords typically have been excavated by glaciers.

frazil ice - Ice crystals in the water column, usually near the water surface. Frazil ice crystals are not oriented in an organized manner, and have the appearance of slush or separated needles, diving through frazil ice you can see that below the main body, the crystals are quite large and separate. The first stage in the formation of sea ice.

frost smoke - Condensed water vapor that forms as a mist above any open sea water in very cold weather.

gale - A strong wind. On the Beaufort Scale - used to gauge the speed of the wind, a gale has winds of 39 to 46 miles per hour (62 to 74 kilometres per hour). Gales are common in Antarctica.

GCM - General Circulation or Global Coupled Model.

geomagnetic pole - If the Earth's molten metallic core is imagined to be a giant bar magnet, the Geomagnetic Pole is where you would expect the magnetic field lines to converge. But ocean currents, mountains and solar activity mess things up, similar to how a compass can be confused if you hold it near something metal. Because of this while the geomagnetic pole is where the needle of a compass should point straight downwards, it is the magnetic pole where this is actually the case. The Magnetic Pole can move many kilometres in a day, whereas the Geomagnetic Pole moves much more slowly. The geomagnetic poles aren't fixed and wander about, currently the south geomagnetic pole is about 1160 kilometres (725 miles) north of the south geographic pole.

geothermal - Geo - earth, thermal - heat. Heat generated within the interior of Earth. Visible indications of geothermal activity are geysers when underground water comes into contact with a heat source, such as hot rocks near a volcano. In Antarctica, Deception Island is geothermally active, there are also thought to be several regions on the continent where glaciers are melted from below by geothermal heat making them flow more quickly at those regions.

GHG - Green House Gas

GIC - Glaciers and Icecaps

GIS - Greenland Ice Sheet

glacial erosion - The wearing down of the Earth's surface by glaciers. Rock debris at the bottom of a glacier scrapes and erodes the surface over which the glacier flows like a giant hugely heavy piece of sand paper.

glaciation - The formation, activity, and retreat of glaciers through time. The glaciation of a region refers to the growth of ice over that region. Large parts of the Northern Hemisphere experienced glaciation in the past - ice ages.

glacier - A river of ice. Usually a mixture of ice, air, water, and rock debris formed at least partially on land. They are large enough for the ice to flow with gravity.  Glaciers can be small valley glaciers, ice streams, ice caps, and ice sheets. The term glacier also includes ice shelves if they are fed by glaciers. Freshwater.

grounding line - The point a glacier that is flowing into a sea or lake loses contact with seafloor and begins to float as an ice shelf.

Heat reservoir - Places where heat is absorbed and then distributed slowly to the surroundings. Oceans and other large bodies of water act as heat reservoirs. They absorb heat and slowly pass it to the atmosphere. This is one reason why coastal areas and islands never get as cold as areas inland in winter. The heat doesn't have to be very great, the sea can still seem very cold, as long as it is above the surrounding air temperature, heat will be transferred.

ice cap - A large dome-shaped mass of ice that is thick enough to cover all the landscape beneath it so appearing as a smooth coating of ice. Ice caps are smaller than ice sheets, usually under 50,000 square kilometres (19,000 square miles). Ice caps can deform and flow with gravity and spread outward in all directions. Freshwater.

ice foot - A "shelf" of ice that forms around many Antarctic shores in the winter time. Sometimes formed by sea spray, often formed where sea-ice joins the land, as the tide rises and falls, a layer of ice is deposited which builds up. Once the sea ice blows out in the spring a distinct ledge several feet high is left behind that can be difficult to cross for men and also for animals. Sea-water

ice sheet - A large mass of ice that is thick enough to cover the landscape beneath it so appearing as a smooth coating of ice. Ice sheets can deform and move with gravity, they are larger than ice caps. Ice sheets cover much of Greenland and Antarctica. Freshwater.

ice shelf - A large flat-topped sheet of ice that is attached to land along one side and floats in the sea or a lake. Formed where a glacier or ice shelf has reached the water and kept flowing, it is fed from the landward side and eroded from the seaward side by the calving of icebergs and melting. Freshwater.

ice stream - A rapidly moving current of ice in an ice sheet or ice cap. Ice streams flow more quickly than the surrounding ice and remove ice from the ice sheet. Antarctic ice streams may flow about one kilometre per year (0.6 miles per year). Freshwater.

ice tongue - A long, narrow, projection of ice out from the coastline, similar in origin to an ice shelf, but usually formed where a valley glacier flows rapidly to the sea or a lake. Freshwater.

iceberg - A large piece of floating ice that has calved, or broken off, a glacier or ice shelf. Icebergs occur in lakes and the ocean and can be vast, the size of islands or small countries. Freshwater.

katabatic winds - Wind that results from dense, cold air flowing down a slope by gravity. Over Antarctica, air cools over the high plateau region and flows towards the coast, by the time it gets to the coast it can have reached extreme speeds and blow continuously for weeks.

land-based ice sheet - a large body of ice with a base mostly above sea level. The East Antarctic Ice Sheet is a land-based ice sheet. Freshwater.

lapse rate - The change in temperature associated with a change in elevation. When climbing a mountain, the temperature falls approximately 1°C for every 100m in altitude gained.

latitude - Imaginary lines that allow for the measurement of position north or south of the equator. Latitude is measured in degrees (one degree - 60 nautical miles, or 111 kilometres). The equator is at a latitude of 0° and the poles lie at latitudes of 90° north (North Pole) or 90° south (South Pole). Lines of latitude differ in length according to how far north and south they are.

lead - Long, narrow opening or fracture in sea ice. Leads can be useful to shipping because they do not have to waste fuel and time by breaking ice, they can be disastrous if travelling over sea-ice as the path is no longer there. Leads are also useful to seals and whales that can use them to breathe and for birds that can feed on marine prey through the lead.

LIG - Last Interglacial

longitude - Imaginary lines that wrap around the Earth intersecting at the north and south geographic poles. Lines of longitude are numbered from 0° (the Greenwich Meridian, passing through Greenwich in London, England) to 180°. Longitudes are called east if they fall east of the Greenwich Meridian, and west if they fall west of the Greenwich Meridian. Lines of longitude are all of the same length.

maritime - Bordering or next to the ocean or sea. Maritime climates are oceanic climates, and are milder than the inland climates because of the moderating influence of the sea which acts as a huge heat sink absorbing heat in the summer and giving it out in the winter.

MIS - Marine Isotope Stage

NAS - National Academy of Sciences

NRC - National Research Council

PDF - Probability Distribution Function

PIG - Pine Island Glacier

PIIS - Pine Island Ice Shelf

Polar Front (Antarctic Convergence) - A surface boundary where which the colder, north flowing Antarctic Surface Waters sink beneath warmer circulating waters. This marks a change in the oceans surface temperature and also chemical composition. North of the convergence, the area is known as the sub-Antarctic.

Polar Plateau - The relatively flat, high altitude central region of the East Antarctic Ice Sheet. The plateau has an average height of 2000 meters (about one mile) above sea level and a smooth surface with a small slope towards the coast in all directions.

polynyas - A polynya is an area of open water in pack ice or sea ice, they may be kept open by constant winds or the upwelling of water and so tend to recur in the same locations year after year.

precipitation - Rain, snow, hail, sleet etc. moisture falling from clouds to the surface of the Earth, usually as rain, snow, and ice. The amount of precipitation is always measured as water or rain equivalent so allowing for the fact that snow can have various structures and densities.

reflectivity - The amount of light or energy that bounces off a surface relative to the amount of light or energy that reached the surface. A mirror is an example of an object with high reflectivity. The ocean has low reflectivity. Reflectivity may also be called albedo.

RIS - Ross Ice Shelf

RCP -  Representative Concentration Pathways

RSLR - Relative Sea Level Rise

salinity - The amount of dissolved salts contained in sea water. The average salinity of sea water is 35 parts per thousand, but can vary with location.

sea ice - A general term for any ice that forms from frozen seawater. Sea ice covers large parts of polar waters in the winter and melts back each summer.

SLR - Sea Level Rise

South geographic pole - 90°S. The south geographic pole is the southern location where the axis of rotation of Earth intersects Earth's surface.

South geomagnetic pole - The point on Earth's surface in the Southern Hemisphere where the axis of the Earth's magnetic pole intersects. The south geomagnetic pole is approximately 1160 kilometres (725 miles) north of the south geographic pole (think about it). The south geomagnetic pole is tilted about 12 degrees to the axis of rotation of the Earth (geographic pole).

South magnetic pole - the point on Earth's surface that a south-seeking compass needle seeks. At the South magnetic pole a compass needle will point vertically downwards. This point is currently off the coast of Wilkes Land and wanders around.

SRES - Special Report on Emission Scenarios

SST - Sea Surface Temperature

stratosphere - The layer of the atmosphere that is above the troposphere, it extends from approximately 10 to 50 kilometres (6 to 31 miles) above Earth's surface. The upper region contains the ozone layer.

subglacial - Underneath the glacier.

supercooled - A condition when water is still liquid even though it is at a temperature at which it normally would freeze. Often under these conditions a small physical movement a small knock or tap will cause the water to freeze almost immediately.

tabular iceberg- A flat-topped iceberg, like a table. Freshwater.

terrestrial - Dry land.

TG - Thwaites Glacier

tide crack - Any crack in sea ice that is caused by the rise and fall of the tide. As the tide rises so the area of the sea increases and a crack forms, as the tide falls, so the area decreases and the crack closes. Often form around offshore rocks, between the shore and sea-ice, around grounded ice bergs or even stretching for miles between islands.

tongue - A mass of ice projecting from a glacier into the sea. It is still fixed to and forms a part of the larger glacier. freshwater.

trade winds - One of three major circulation cells in both the northern and southern hemispheres. The trade winds from approximately 0° to 30° north or south latitude. Within the regions of the trade winds, prevailing winds blow toward the west. They were given their name as in the days of sailing ships, they aided the progress of the ships and hence the trade of goods carried by those ships.

upwelling - An oceanographic term, the rising of deeper waters to replace surface waters. Upwelling often brings waters rich in nutrients to the surface, resulting in a region where ocean productivity is high.

West Wind Drift (Antarctic Circumpolar Current) - A Southern Ocean surface current flowing east and driven by westerly winds. The West Wind Drift carries a large volume of water and it is a strong current because no continents are in the way of the flow path.

WAIS - West Antarctic Ice Sheet (the last marine ice sheet in the world).

WCRP - UN, WCRP Task Group on Sea Level Variability and Change.

44
An important part of the scientific method is to challenge prevailing misconceptions in order to gain a deeper insight into the true nature of a situation.  Most of my other threads about the potential abrupt collapse of the WAIS force on explaining my proposed hazard analysis; with little emphasis (except for by my brief critique of Pfeffer et al assumed [or expert opinion] limits on ice mass loss rates from WAIS) on challenging prevailing misconceptions on this matter.  Therefore, I open this thread focused on challenging what I believe to be prevailing misconceptions, and I begin in this post by challenging some of the mis-beliefs about the probability of occurence of the various SRES, and RCP, radiative forcing scenarios:

The global economic system that is driving the creation of man-made radiative forcing components is also system with net positive feedbacks encouraging the creation of more radiative forcing components, because fossil fuels have been historically associated with energizing the modern capitalistic system; thus all probability density functions associated with estimating man-made radiative forcing component emission scenario from the current modern capitalistic system will have a low probability of low emission and with have a fat tail for higher emissions.  This can be illustrated in the first attached image by noting that the AR4 SRES B1 family of emissions were developed by the IPCC to simulate the "Low" scenarios required to keep global temperature from raising 2oC above the 2000 temperature levels (and were nominally adopted by V&R as input to their "Low" SLR projections) in-line with the UN Kyoto Protocol goals; however, at the  17th Conference of Parties, COP 17, to the United Nations Framework Convention on Climate Change, held in Durban, South Africa in 2011, representatives of the Parties agreed to replace the Kyoto Protocol goal of a 2 oC global temperature rise, with a new "legal framework" that will allow global temperatures to rise to nominally 4 oC, thus indicating the probability function of anthropogenic emissions represented by smooth distribution of the 2007 data (a prior), could be transformed by future Bayesian Learning analysis into a posterior with a more asymmetric distribution due to the possible elimination of the SRES B1 (Full Participation) family of emission scenarios, and the addition of new high-end scenarios due to such factors as higher climate sensitivity than assumed.
For the "Full Participation" projection probabilities to be correct, strong negative feedback would have been implemented (by either policy or technology/market forcing); however, observations from 2007 to the Durban COP17 meeting in December 2011, indicates to most reasonable observers that this family of SRES B1 probabilities (limiting temperature increase to less than 2oC) is at risk of not happening and a Bayesian Learning analysis may numerically verify this.  Currently, most observers realize that if strong negative policy feedback can be negotiated in the Durban legal framework to be negotiated by 2015 and possibly implemented by 2020, then the best family of probability that can be hoped for is similar to the SRES A1B "Developing Countries Delay" scenario, while if weak negative feedback occurs then probabilities similar to the SRES A1FI "Reference" scenario are more likely.  This can be understood by examining the second attached figure, for the results of representative Bayesian Learn climate change analysis where: (a) the top graphs for Data from the 1961-1998 show on the left panel two blue Priors together with a red curve of observations resulting in the Posterior in the panel on the right; and (b) the middle graphs for Data from 1970 to 1998 show on the left panel the same two Priors as in the top graphs together with more recent observations indicated by a red curve to the right of the red curve in the top graph; which result in the Posterior shown in the right middle panel with the new probability curve shifted to the right of the curve in the top left panel; and (c) the bottom graphs for Data from 1980 to 1998 show the same two Priors together with still more recent observations shown by the red curve in the bottom left panel, which after Bayesian Learning analysis results in the Posterior in the bottom right panel which is still further to the right of the Posterior shown in the middle right panel.  This sequence of Bayesian analyses for a representative system with strong net positive feedback indicates how only a few years (or decades) of observations can result in the collapse of hypothetical probabilities for families of projections such as SRES B2/A1B, or RCP 3/4.5, converging the probabilities towards those for the families of projections associated with SRES A1FI or RCP 8.5.  It is also important to note that if new, or stronger net positive feedbacks are identified, then after Bayesian Learning it is probable that the Posterior would shift toward higher projections than such previous Priors as those associated with SRES A1FI or RCP 8.5.

A similar progression of Bayesian Learning from future observations related the collapse of the WAIS could transform the current "fat-tailed" of my proposed PDF for the risk of abrupt SLR for California (see the third image) into a more peaked posterior PDF for high sea levels as we progressively get closer to 2100.

45
In addition to the "Antarctic Images" thread started by Susan, I am starting this thread of links to internet sites to monitor regarding the risk of the potential collapse of the WAIS.  Many of these links will deal with related topics such as SLR, Ocean Currents, and abrupt climate change; and some links will be to data that is not updated frequently; nevertheless, hopefully the information from such websites will help in identifying/confirming ice mass loss trends from the WAIS and the EAIS, as soon as practicable.

First, I provide the following links to Modis Rapidfire, where changes in the ice surface can be monitiored:

http://rapidfire.sci.gsfc.nasa.gov/subsets/?project=antarctica

http://rapidfire.sci.gsfc.nasa.gov/imagery/subsets/index.php?project=antarctica_risco_areas


Second, I provide the following links to GRACE Satellite output (where the data is currently being changed to a new format, so the reduced data presented is aging and the new data is not reduced).  This data is critical because it directly measures ice mass loss:

http://grace.jpl.nasa.gov/data/gracemonthlymassgridsoverview/

ftp://podaac-ftp.jpl.nasa.gov/allData/tellus/L3/ocean_mass/RL05/browse/jpl/


Third, with regard to Sea Level Rise, SLR, I provide a link to NOAA's website:

http://ibis.grdl.noaa.gov/SAT/SeaLevelRise/LSA_SLR_timeseries_global.php

Fourth, I provide a link to the Imbie site, which focuses on ice sheet contributions to SLR:

www.imbie.org

Fifth, I provide a link to the University of Colorado SLR website:

http://sealevel.colorado.edu/

The following site is periodically updated with information about how many current GCM projections underestimate our current situation:

http://www.global-warming-forecasts.com/underestimates.php

I will periodically add additional links, but please feel free to add links of your own.

46

It is likely that many of readers consider my hazard analysis posts on the potential for abrupt SLR from a complete, or partial, collapse of the WAIS this century, as constituting an improbable chain of events.  Nevertheless, it is well known that people heavily discount the future, and as a result are frequently surprised by "Black Swan" events; which, as discussed in the "Philosophical" thread, happen much more frequently than most people are willing to entertain.  Therefore, I am opening this thread to discuss the consideration that the available paleo-evidence  may be adequate to serve as a form of calibration or as a "guarantor"  that the risk of such abrupt SLR scenarios are sufficiently likely, for authorities to enact regulations requiring that susceptible infrastructure should be evaluated for resiliency against such a Maximum Credible (slr) Event, MCE.

What I mean by a "guarantor" is something akin to the "invisible-hand" of capitalism, or more accurately, closer to a chain of positive feedback mechanisms that create a strange attractor (such as the "Lorenz Attractors", see Chaos Theory [also note that the Black Swan Theory, BWT, is rooted in chaos theory]) that may have driven Heinrich-like, and associated Dansgaard-Oeschger (D-O) Events.  Indeed, the Bollings Warming/Meltwater Pulse 1A event (see the first image, and note that based on boring in coral in Tahiti Meltwater Pulse 1A included significant SLR contribution from marine ice sheets previously located on the continental shelf of West Antarctica) is but one of a series of other Dansgaard-Oeschger/Heinrich Events, that indicate the sensitivity of marine ice sheets to rapid collapse, thus indicating the likely potential abrupt collapse of the last remaining marine ice sheet, the WAIS.

For those not familiar with Chaos theory or Lorenz Attractors, I provide the following from Wikipedia:
"In 1963 Edward Lorenz was studying the patterns of rising warm air in the atmosphere. It was known at the time that air could start to move if it came into contact with a warm object. The properties of air are such that it expands a lot when heated, it is a good insulator and it flows with relative ease - technically speaking, it has a high Rayleigh number. Think of a large hot air mass in the atmosphere as rising like a hot air balloon in the shape of a mushroom cloud (!). Based on known hydrodynamics Lorenz derived a set of simplified equations for this movement and found something amazing. For certain values of the parameters, the overall movement of the atmospheric air was oscillating unpredictably (Lorenz 1963):
A major concern was that for small changes in starting conditions the system would always have an unpredictable outcome. This was the discovery of deterministic chaos and we knew there and then that we would never know the weather more than 10 days ahead without using disproportionate computing power with very little pay-off. Naturally, scientists knew about chaos from studying turbulence, which is not both smooth (deterministic) and unpredictable.
When Lorenz looked closer at his graphs, something exciting happened. A peculiar regularity emerged when he plotted the curves against each other: they were attracted to something never leaving a boxed volume. It was strange, because it was not a simple shape, but rather an entire subspace of points strangely smeared into three dimensions (see the second image).
Even stranger, the structure is occupying not just a two dimensional surface but something which is more than two dimensional and less than three dimensional: it is two-dimensional plus a fraction. It exists in a so called fractal dimension. It never truly intersects itself thus committing every trajectory to infinite solitude. The object was therefore aptly dubbed a strange attractor.
A closer look reveals where the unpredictability arises. The blue and the magenta curves are closely following each other for a time. Suddenly the magenta curve takes a wild hike and quickly finds itself far away from its companion curve (see the third image). This is known as sensitivity to initial conditions, which is seen in everyday weather."
The fourth image (from climate skeptic) illustrates how while the trend of global temperature rise is not chaotic (and can be reliably projected), periodic chaotic strange attractor (e.g. Lorenz Attractor) temperature rise events can happen (and possibly increase with rising temperature).  Perhaps the most famous/relevant example of such a periodic chaotic strange attractor (that may be increasing with rising global temperatures) is the ENSO; recent changes in which I have repeatedly stated may contribute to the rapid degradation of the WAIS, including by: (a) the current 13-year long El Nino hiatus period pumping more ocean heat content directly from the tropics (particularly the Pacific Tropics) into the ACC and thus warming and expanding the volume of the CDW; and (b) changes in ENSO have a influence of both SAM and on storms in the Southern Ocean.

Unfortunately, with regard to Heinrich events, many researchers have not previously recognized both: (a) the rapid response atmospheric/ocean periodic chaotic strange attractor mechanisms (such as the ENSO strange attractor mechanism); and (b) the importance of the short-term synchronistic (strange attractor) mechanism between Northern Hemisphere (NH) ice and Southern Hemisphere (SH) marine ice sheets.  Therefore,  I am postulating that Heinrich like events (possibly including the potential collapse of the WAIS by 2100), can also follow a pattern, of a general trend of rising radiative forcing (such as our current anthropogenic forcing) with periodic strange attractor events (ie the Heinrich [or pending WAIS collapse] events supported by ENSO and NH/SH ice synchronicity strange attractor subsystems) .   In my next series of posts, I will explore this postulated Heinrich/D-O periodic chaotic strange attractor pattern, superimposed on a longer-term global warming trend; and also how the repeated collapse of the WAIS during past interglacial peak periods has gouged troughs in the West Antarctic seafloor that increase the risk of the collapse of the current WAIS.





47
Due to other time commitments I previously omitted opening a thread focused on a hazard analysis for the Filchner Ronne, and the Ross, Ice Shelfs, (FRIS/RIS); and I lumped this topic together with other topics in the "Collapse Main Period" thread.  Unlike the Bellingshausen/Amundsen Sea marine ice sheets where a significant portion of the ice mass loss contributes directly to SLR; most of the FRIS/RIS ice mass loss will not contribute to SLR, and furthermore, I postulate that the acceleration of ice mass loss from the marine ice sheets in the Weddell and Ross Sea areas (which do contribute to SLR) will not happen until the FRIS/RIS rapidly degrade sometime after 2060.

However, it should be noted that the conventional thinking is that the cold FRIS/RIS ice shelves will largely remain intact until well after 2300; and that most researchers will likely dismiss my hazard assessment of the risk of the FRIS/RIS collapsing soon after 2060 as being without merit, possibly due to their belief in the stationary nature of both: (a) the water adjoining the FRIS/RIS  in the Continential Zone, within the Continental Water Boundary, CWB, shown in the first re-posted image; and (b) the protective circulation pattern beneath a cold ice shelf that helps to keep warm CDW out from beneath as cold ice shelf, as indicated in the second accompanying figure for the FRIS (at the Filchner Trough) per Hellmer et al 2012.

In the series of follow-up posts I hope to contrast my different scenarios for FRIS and RIS from 2012 to 2060 in order to clarify why both of them may collapse shortly after 2060 by following two different paths.

48
Antarctica / Recommendations and Summary wrt the WAIS Collapse Hazard
« on: March 08, 2013, 10:47:59 PM »
It may be more traditional to present the summary before the recommendations, but as I like to think that the recommendations for further research are more important (on the even small chance that some researcher follows-up on even one of the recommendations); therefore, I provide the following abbreviated list:
Possible Office Studies:
- Publish a paper including the results of the October 2012 Icebridge radar survey of the Thwaites Gateway, in order to document any possible subcavities located there.
- Publish a paper addressing the possible correlation between the GRACE satellite reported changes in sea level around the Weddell, Bellingshausen, and Amundsen Seas, and glacier ice melt in these areas.
- Apply the mathematical procedures develop to document the "Jakoshavn Effect", to the geometry and boundary conditions of the Thwaites drainage basin.
- Develop a sophisticated box model for the Thwaites Glacier (including the postulated subglacial cavity) to see how the grounding line retreats into the BSB.
- Run various ice sheet models with the initial starting conditions that have been presented here; particularly the conditions postulated for the Thwaites Glacier after 2060, including the basal melt rate measured at the WAIS-Divide bore hole.
- Run ice shelf models for both FRIS and RIS with CDW (with flow and temperature parameter calibrated to match the reduction of AABW in these respective areas) introduced beneath them in order to evaluate the rate of ice shelf thinning thru 2100.
- Try to hydraulically model the advective (horizontal) interaction between the PIG and Thwaites system to determine whether there is any synergistic advective action.
- Model the hydraulic action of the postulated interconnected sea passageways and side spurs, and their possible influences on local currents around a degraded WAIS (after 2070).
Possible Field Studies:
- Send a research vessel to the Northeast edge of the FRIS to see whether it is true that warm CDW is already entering the Filchner Trough, and monitor the water flow at outer edge of the RIS for indications of possible CDW fluxes.
- Conduct high-resolution ground penetrating radar examinations of the grounding line of the marine ice sheets for Basins A & B near the Southwest edge of the Filchner Ice Shelf, in order to see whether the grounding line has begun to retreat down the negative slope.
- Refine the ground penetrating survey of the ice in the Thwaites drainage basin, in order to more accurately locate, and delineate, the subglacial lakes in this area.
- Deploy a submersible ROV to survey the: (a) Thwaites Hollow/Subglacial cavity; and (b) the gateway to the Ferrigno Glacier to see if a subglacial cavity has formed there.

49
Antarctica / Consequences of ASLR from a WAIS Collapse
« on: March 06, 2013, 04:30:50 PM »
No hazard analysis would be complete without some evaluation of consequences as risk is equal to probability of occurrence time consequences.  I will start this evaluation of consequences by the most obvious impact of inundation.  As it is beyond my means to develop true inundation maps for future cases combining the effect of local tides/storm surge/storm tide/regional subsidence/regional variabilities together with the "finger print" effect for the Maximum Credible Event, MCE, for abrupt RSLR (see the graphs for California for this MCE RSLR values); therefore, I will just post a few images of inundation for a 6m increase in local sea level (see accompanying images); and I will make the following general comments:
-  The inundated areas worldwide contain over 100 trillion dollars of captial assests which merit some effort of resilient defense (which is currently not occurring).
-  The increase in water depth, due to ASLR, will locally amplify the amplitude of short term changes in sea level such as for: tides, storm surge and storm tides.
- Flooding (and coastal errosion) of the relatively flat coastal plains of Alaska and Siberia will introduce relatively warm ocean water on top of permafrost (and buried methane hydrates), which will accerate GHG emissions from these flooded areas.

There are a large number of other consequences and I will add to the list in the next few days, and then I hope to open a Summary Thread with Recommendations for further research.

50
Antarctica / Discussion of WAIS Collapse Main Period from 2060 to 2100
« on: March 03, 2013, 02:55:49 AM »
Due to complexity of a hazard analysis for the potential abrupt collapse (either partial of full) of the WAIS, I have made many posts already, and for the sake of brevity I will try not to repeat the information/postulations presented in the "Potential Collapse" thread, nor the final SLR projections presented in the "Philosophical" thread.  While my hazard analysis for RCP 8.5 50% CL forcing is quite aggressive, projecting a eustatic SLR of about 0.5m for the period from 2000 to 2060 (and about 1m of SLR by 2060 for the 95% CL scenario); my SLR projections for my "collapse main period" are more aggressive still, estimating about 3m of eustatic SLR by 2100 for the RCP 8.5 50% CL case, and just over 5m of SLR by 2100 for the RCP 8.5 95% CL case.  Nevertheless, I hope that the supporting information presented in this thread clarifies the nature and probability of the "Collapse Main Period this Century" from 2060 to 2100.

I will start this "clarification" by providing the first accompanying figure (not previously posted in the "Collapse" thread) showing a plan view of the my RCP 8.5 50% CL scenario estimates of WAIS areas that may have experienced grounding line retreat by 2070.  This figure indicates several significant areas of proposed grounding line retreat including:
(a) the transparent orange area with Jakobshavn Effect acceleration and associated "ice melange" discussed extensively in the thread on the PIG/Thwaites system behavior up to 2060 show the two significant changes: (i) the Eastern trough ice stream has continued to exhibit "Jakobshavn Effect" acceleration behavior and the grounding line retreat for this ice stream has extended about an additional 200km in 10 years, while the grounding line retreat for the Western trough ice stream is proposed to slow dramatically as the seafloor becomes rough at the western end of this trough; and (ii) with the extension of the Western trough ice stream slowed, this allows for the extension of the grounding line retreat in the Southernly direction into several different branching troughs in this direction at a slower rate than for Eastern trough ice stream.
(b) the Ferrigno Subglacial cavity showed marked rate of extension driven largely by advection associate with relatively high CDW in the Bellingshausen Sea (with no Jakobshavn Effect), while the PIG subglacial cavity extension (ie groundling line retreat) remains slow due to rough seafloor conditions.
(c) The grounding line retreat for the Siple Coast ice stream accelerates as the Ross Ice Shelf is assumed to provide rapidly degrading buttressing support.
(d) The Weddell Sea Embayment, WSE, glaciers show a major surge of grounding line retreat due both to a projected re-direction of advective warm CDW into the WSE (below the Filchner-Ronne Ice Shelf), and due to ideal seafloor conditions (in the area of indicated grounding line retreat) to support the classic gravitationally driven marine ice sheet retreat behavior addressed in the second accompanying figure).  I will discuss the WSE proposed surge of grounding line retreat (by 2070) in the next post.

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