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Lennart van der Linde

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2250 on: December 13, 2019, 04:47:16 PM »
Hansen's model(s), that he has published in several papers since 2005, is in my opinion not accepted science... He speculates that exponentially increasing ice losses primarily from the Antarctic will cause the AMOC/SMOC to shut down within a few decades, which will trigger more large-scale climate changes. But this is just a modelling excercise, based on incomplete theories, and totally insufficient data, especially from the ever important Southern Ocean... And we aren't yet able to adequately model deep convection in the tropics, where most of energy transfer takes place. Etc.etc., just to point out that we shouldn't get panic because of some computer simulations that is essentially GIGO.
...
I agree about the urgency of climate policies to avoid the 'tipping points'. But I think that:
i. The capitalist market forces already strongly favouring renewables due to pure price competitiveness; and
ii. The kind of aggressive climate policies now implemented by the EU and some other OECD countries; will be quite sufficient to avoid those tipping points in reasonable time, say 40 years. I think we already left the exponential growth of CO2, and that we are now in linear growth. In as little as 5-10 years I hypothesize that we will see flat CO2 growth.

I hope you're right, but would not count on it. Hansen has a history of becoming accepted science after first being contested (by some). He may be wrong this time, but it seems very possible that he's right again. And many of his suspicions are being shared by prominent and respected scientists in their fields. Waiting with stronger mitigation until we have more certainty about the accuracy of their suspicions implies risking being too late (even more than we already are), precisely because of the inertia in the climate system, which Hansen emphasizes. Gambling with such stakes involved seems very irresponsible. To minimize the unacceptably large risk of passing dangerous tipping points we have to reach net zero globally within 30 years, not 40 years, or as fast as possible, as Hansen says. This means the EU and other richer parts of the world have to reach net zero in about 20 years, or pay poorer countries to reduce their emissions even faster than otherwise. Where the market can do this, great. But where the market cannot do this fast enough yet, stronger policies will have to accelerate their development. The EU is making some progress in the right direction, at least on paper, but more will be needed and has to be implemented. My two cents.

Tor Bejnar

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2251 on: December 13, 2019, 04:48:33 PM »
Hefaistos,
Can you clarify what you mean?
...
I agree about the urgency of climate policies to avoid the 'tipping points'. But I think that:
i. The capitalist market forces already strongly favouring renewables due to pure price competitiveness; and
ii. The kind of aggressive climate policies now implemented by the EU and some other OECD countries;

will be quite sufficient to avoid those tipping points in reasonable time, say 40 years. I think we already left the exponential growth of CO2, and that we are now in linear growth. In as little as 5-10 years I hypothesize that we will see flat CO2 growth.
...
and
...
I agree about 350 as a good goal.
I think we're getting out of CO2 growth pretty soon (5-10 years), and we will see a stable decline starting well before 2050.
In one post you indicate CO2 growth will be flat within 5-10 years.  I presume this means neither acceleration nor deceleration - if one year's increase is 1.0 ppm, the next year's increase is also 1.0 ppm.  (This is certainly an improvement on the current acceleration of CO2 growth.)

In the next post you indicate CO2 growth will end within 5-10 years.  I'm pretty sure this means we will have reached peak atmospheric CO2 concentrations.   (This would be good news indeed.)

I, too, think 350 ppm is good a '1st iteration' goal.  Where we are in the current Milankovitch cycle tells me we want a thicker CO2 blanket to prevent a significant glacial advance.  [Would that be our current concern!]  (Future climate models will be able to help us discern how much 'blanket' we need to compensate for variations in eccentricity, axial tilt, precession of the Earth's orbit, solar intensity, etc.)
Arctic ice is healthy for children and other living things.

Lennart van der Linde

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2252 on: December 13, 2019, 04:56:04 PM »
Hefaistos,
Can you clarify what you mean?

Indeed, if you share 350 ppm as a desirable goal, then this implies net zero globally by 2050 to minimize the risk that tipping points will be crossed that will make 350 impossible to reach, as far as I understand.

Tor Bejnar

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2253 on: December 13, 2019, 05:38:51 PM »
...
Indeed, if you share 350 ppm as a desirable goal, then this implies net zero globally by 2050 to minimize the risk that tipping points will be crossed that will make 350 impossible to reach, as far as I understand.
A "350 ppm goal", to me, does not imply we reach peak CO2 concentrations as late as 2050 (which is what arriving at "net zero" means to me - am I off?).  I would truly love to see peak CO2 concentrations around 2025-30 and Earthlings causing our achieving the 350 ppm goal within 50-75 years of that.  (And people thought WWII-era industrial [etc.] focus was intense...)  Anything less aggressive then that will allow more tipping points to be crossed (one or two appear to have already been crossed - permafrost and Amazon) and therefore making it more difficult to achieve (as you suggest).

I would very much like the Earth to be livable for the grandchildren of today's youth (that is, youth of 'all' species [maybe without a pathogen or two]).
« Last Edit: December 13, 2019, 07:29:42 PM by Tor Bejnar »
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nanning

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2254 on: December 13, 2019, 06:22:59 PM »
I want to mention that  AGW- and biosphere-collapse effects have happened 'faster than expected' by science. Every time the science and understanding improves, it paints an even darker picture of the future. I read a lot about improved science from the great series of articles by AbruptSLR in this thread.

Tipping points may likely be crossed 'faster than expected'.
High time to stop having respect for complacency.
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Lennart van der Linde

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2255 on: December 13, 2019, 07:42:53 PM »
I would truly love to see peak CO2 concentrations around 2025-30 and Earthlings causing our achieving the 350 ppm goal within 50-75 years of that.

Me too, but is it possible to reach net zero global emissions and peak concentrations in 5-10 years? I've seen no reasoned argument how this could be done, but if anyone has, I'm curious to hear it.

nanning

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2256 on: December 13, 2019, 07:54:25 PM »
https://en.wikipedia.org/wiki/Martial_law

Quote
Martial law is the imposition of direct military control of normal civilian functions by a government, especially in response to a temporary emergency such as invasion or major disaster, or in an occupied territory.[1][2]

Martial law can be used by governments to enforce their rule over the public, as seen in multiple countries listed below. Such incidents may occur after a coup d'état (Thailand in 2006 and 2014, and Egypt in 2013); when threatened by popular protest (China, Tiananmen Square protests of 1989, 2009's Iranian Green Movement that led to the takeover by Revolutionary Guards); to suppress political opposition (Poland in 1981); or to stabilize insurrections or perceived insurrections (Canada, the October Crisis of 1970). Martial law may be declared in cases of major natural disasters; however, most countries use a different legal construct, such as a state of emergency.

Apologies for the off-topic post.
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
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sidd

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2257 on: December 13, 2019, 10:03:29 PM »
Does anyone seriously believe that we will achieve 350 ppm CO2 anytime this century absent huge carbon recapture effort ?  I see no way there based on reducing fossil emission alone. Perhaps if we went to

sidd

KiwiGriff

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2258 on: December 13, 2019, 10:11:06 PM »
Quote
Global carbon emissions are expected to hit an all-time high in 2019, scientists say, smashing a previous record set in 2018.

By the end of the year, emissions from industrial activities and the burning of fossil fuels will pump an estimated 36.8 billion metric tons of carbon dioxide into the atmosphere. And total carbon emissions from all human activities, including agriculture and land use, will likely cap off at about 43.1 billion tons.

The estimates were released last night in a new report from the Global Carbon Project, an international research consortium dedicated to tracking the world’s greenhouse gas emissions.
https://www.scientificamerican.com/article/co2-emissions-will-break-another-record-in-2019/

“A famous bon mot asserts that opinions are like arse-holes, in that everyone has one. There is great wisdom in this… but I would add that opinions differ significantly from arse-holes, in that yours should be constantly and thoroughly examined.

We must think critically, and not just about the ideas of others. Be hard on your beliefs. Take them out onto the verandah and beat them with a cricket bat.... Be intellectually rigorous. Identify your biases, your prejudices, your privilege.”.
Tim Minchin

Roughly 50 % of our emissions end up staying in the atmosphere.
Stable emissions would only result in a slowly declining rise in CO2 levels until we reach equilibrium far into the future. 
 

AbruptSLR

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2259 on: December 13, 2019, 10:42:16 PM »
...
“A famous bon mot asserts that opinions are like arse-holes, in that everyone has one. There is great wisdom in this… but I would add that opinions differ significantly from arse-holes, in that yours should be constantly and thoroughly examined.

We must think critically, and not just about the ideas of others. Be hard on your beliefs. Take them out onto the verandah and beat them with a cricket bat.... Be intellectually rigorous. Identify your biases, your prejudices, your privilege.”.
Tim Minchin
...
The title of the linked reference indicates that consensus climate scientists are concerned with how the general public accepts their message about climate change; and that the general public trusts consensus science projections when they create upper and lower bounds which they artificially call best and worst case scenarios; but that the general public lose their trust in consensus climate scientists when these scientists admit that uncertainty means that the artificially defined upper and lower bound are not actually the true best nor the true worst cases.

To me this is another way of saying that: "The road to hell is paved with good intentions", whether by the public, climate scientists or decision makers.

Howe, L.C., MacInnis, B., Krosnick, J.A. et al. Acknowledging uncertainty impacts public acceptance of climate scientists’ predictions. Nat. Clim. Chang. 9, 863–867 (2019) doi:10.1038/s41558-019-0587-5

https://www.nature.com/articles/s41558-019-0587-5

Abstract: "Predictions about the effects of climate change cannot be made with complete certainty, so acknowledging uncertainty may increase trust in scientists and public acceptance of their messages. Here we show that this is true regarding expressions of uncertainty, unless they are also accompanied by acknowledgements of irreducible uncertainty. A representative national sample of Americans read predictions about effects of global warming on sea level that included either a worst-case scenario (high partially bounded uncertainty) or the best and worst cases (fully bounded uncertainty). Compared to a control condition, expressing fully bounded but not high partially bounded uncertainty increased trust in scientists and message acceptance. However, these effects were eliminated when fully bounded uncertainty was accompanied by an acknowledgement that the full effects of sea-level rise cannot be quantified because of unpredictable storm surges. Thus, expressions of fully bounded uncertainty alone may enhance confidence in scientists and their assertions but not when the full extent of inevitable uncertainty is acknowledged."

For example, the IPCC says that forcing scenarios (whether SRES, RCP or SSP) cover the upper and lower bounds of reasonable forcing scenarios.  Yet since the Kyoto Protocol actual forcing has only followed the 'upper' bound assumptions and never the middle or lower bound assumptions.  Furthermore, all IPCC Assessment Reports to date have ignored ice-climate feedbacks; when in reality they should be added on top of the GHG forcing scenarios.

Earth Systems will follow the pathway of the laws of physics and not the opinions of the general public, of consensus climate scientists nor of decision makers; no matter how we all react to uncertainty.
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AbruptSLR

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2260 on: December 13, 2019, 11:17:38 PM »
In the linked reference the authors acknowledge climate uncertainty with the adjustment factor for unrepresented Earth system feedback called (EEsfb).  Unfortunately, their discussion about unrepresented Earth system feedback do not mention ice-climate feedbacks even through these ice-climate feedbacks are clearly present in the paleo-record as indicated by Hansen et al. (2016) and others.

Rogelj, J., Forster, P.M., Kriegler, E. et al. Estimating and tracking the remaining carbon budget for stringent climate targets. Nature 571, 335–342 (2019) doi:10.1038/s41586-019-1368-z
https://www.nature.com/articles/s41586-019-1368-z

Abstract: "Research reported during the past decade has shown that global warming is roughly proportional to the total amount of carbon dioxide released into the atmosphere. This makes it possible to estimate the remaining carbon budget: the total amount of anthropogenic carbon dioxide that can still be emitted into the atmosphere while holding the global average temperature increase to the limit set by the Paris Agreement. However, a wide range of estimates for the remaining carbon budget has been reported, reducing the effectiveness of the remaining carbon budget as a means of setting emission reduction targets that are consistent with the Paris Agreement. Here we present a framework that enables us to track estimates of the remaining carbon budget and to understand how these estimates can improve over time as scientific knowledge advances. We propose that application of this framework may help to reconcile differences between estimates of the remaining carbon budget and may provide a basis for reducing uncertainty in the range of future estimates."

Extract: "We present in equation (1) an estimate of the remaining carbon budget (Blim) for a specific temperature change limit (Tlim) as a function of five terms that represent aspects of the geophysical and coupled human–environment system (equation (1): the historical human-induced warming to date (Thist), the non-CO2 contribution to future temperature rise (TnonCO2), the zero-emissions commitment (TZEC), the TCRE, and an adjustment term for sources of unrepresented Earth system feedback (EEsfb). These terms are visualized in Fig. 1 and are described and discussed in turn below.

Blim=(Tlim−Thist−TnonCO2−TZEC)/TCRE−EEsfb       (1)


Finally, reductions in emissions due to unrepresented Earth system feedback mechanisms (EEsfb, in units of Gt CO2), are the last term in the proposed remaining carbon budget framework (equation (1)). Any Earth system feedback that is not yet incorporated in estimates of the TCRE or that would reduce the applicability of TCRE should be assessed, and accounted for and communicated as part of EEsfb. These feedback processes have typically been related to permafrost thawing and the associated long-term release of CO2 and CH4. However, other Earth system feedback sources that can affect remaining carbon budgets have been identified, including changes in vegetation CO2 uptake linked to nitrogen availability. If unrepresented feedback results in a direct CO2 emission from an ecosystem, the translation to the EEsfb term is direct. However, because of the diverse nature of Earth system feedback, accounting for it through an adjustment in CO2 emissions is not always straightforward. For example, if a feedback system results in the release of other greenhouse gases or affects the Earth system through changes in surface albedo, clouds or fire regimes, for example, its contribution needs to be translated into an equivalent CO2 correction term (see refs 89,90 for example). Because most Earth system feedback is either sensitive to rising CO2 or to variations in climate parameters, it is expected that these contributions are scenario-dependent, nonlinear, and in some cases realized over longer timescales only. This adds to the complexity of the translation into a CO2-equivalent correction term, and makes EEsfb an uncertain contribution. EEsfb could be estimated either for the time at which global net CO2 emissions become zero or until the end of the century or beyond, assuming anthropogenic CO2 emissions are kept at net-zero levels but feedback mechanisms continue to change over time. Finally, scenario-independent Earth system feedback that scales linearly with global average temperature increase could also be incorporated by adjusting the TCRE, as long as it is not double-counted in both EEsfb and TCRE."

Edit, the caption for the first attached image is as follows:

Caption for the first image: "The schematic shows how the remaining carbon budget can be estimated from various independently assessable quantities, including the historical human-induced warming Thist, the zero-emissions commitment TZEC, the contribution of future non-CO2 warming (consistent with global net-zero CO2 emissions or otherwise) TnonCO2, the transient climate response to cumulative emissions of carbon (TCRE), and further correcting for unrepresented Earth system feedback EEsfb. The grey shading illustrates how uncertainty in TCRE propagates from the start point. Arrows and dashed lines are visual guides illustrating how the various factors combine to provide an estimate of the remaining carbon budget. Besides estimating the remaining carbon budget Blim, the framework can also be applied to understand, decompose and discuss estimates of carbon budgets calculated by other methods. The relative sizes of the various contributions shown in this schematic are not to scale."

Next, I provide the second image that shows that a symmetrical PDF for a Earth system feedback results in a right-skewed PDF for climate sensitivity.  Thus Rogelj et al. (2019) are at least erring on the side of least drama by showing a shaded area about TCRE that is symmetrical when at least it should be right-skewed.  Furthermore, in addition to the fact that Rogelj et al. (2019) do not cite ice-climate feedbacks as a source of unrepresented Earth system feedback (EEsfb), they also do not cite that the rate of change of radiative forcing can have a nonlinear impact on EEsfb, and it is also not clear Rogelj et al. (2019) should be showing the same linear analysis for the 1.5C limit as for the 2C limit, when many feedback system are known to increase nonlinearly with increasing temperature.  Lastly, I do not like the fact that the first image (Fig 1) by Rogelj et al. (2019) shows a carbon budget from the middle of the shaded area for unrepresented Earth system feedbacks (which should at least be right-skewed) as this implies that it is fine to take a 50%-50% chance with the well being of the world.

Edit2: Also, when looking at Fig 1 it appears to me that the shaded area about TCRE is left-skewed and if so, to me this indicates bias on the part of the authors to err on the side of least drama.

Edit3: I also note that the proportion of the height of the 'historical human-induced warming' to the height of the 'Global warming limit of interest' is deceptive as GMSTA in 2019 will be over 1.1C and the only two warming limits under consideration are 1.5C and 2C and the ratio of 1.1 to either 1.5 or 2 is no where near that implied by this Fig 1 which again implies the bias of the authors to err on the side of least drama.
« Last Edit: December 14, 2019, 04:08:21 PM by AbruptSLR »
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AbruptSLR

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2261 on: December 14, 2019, 12:08:32 AM »
Does the fact that we have not yet found intelligent life in the universe imply that many such past alien civilizations overshot their sustainability limit?

Title: "Are We Alone? Maybe. The Better Question Is, Can We Survive?"

https://www.nationalgeographic.com/science/2018/07/are-we-alone-in-the-universe--maybe--the-better-question-is--can/

Extract: "Whether we're alone in the universe depends on whether alien societies overcame the climate change their advances created, says a new book.

How bad does the probability of forming a civilization on a random planet have to be for us to be alone, for us to be the only time in the entire history of the universe that there’s ever been a civilization? That number is 1 in 10 billion trillion.

That number tells me that the only way that we can be the only civilization in cosmic history is if the odds are that low or lower. As long as there’s a probability larger than that, then it has happened before. So unless nature is really perversely biased against forming civilizations then there have been others.

Whether there are others in existence today, I cannot answer. It all depends on this important factor in the Drake Equation, the average lifetime of a civilization. You could have planets creating civilizations all the time, but if nobody makes it to more than, say, 200 years, then right now we would be living in a sterile galaxy. We can say that, yes, there have probably overwhelmingly been civilizations before us. The next step is, does anybody last long, particularly when climate change is going to be a natural consequence of civilization-building?"
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Tom_Mazanec

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2262 on: December 14, 2019, 12:26:22 AM »
It may be different limits than climate change.
Pretend civilization arose in the Ediacaran https://en.wikipedia.org/wiki/Ediacaran
CO2 would start out at 4500 ppm. Our 2019 CO2e would be about 4720...about 5% higher.
Assuming ECS of 3˚ C then the change in temperature would be about 1/16 of 3˚ or about 0.2˚ C...quite survivable. We could put twice as much ∆CO2e and only raise it another 0.2˚. By then we would have depleted recoverable fossil fuel.
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Hefaistos

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2263 on: December 14, 2019, 08:24:52 AM »
Hefaistos,
Can you clarify what you mean?
...
I agree about the urgency of climate policies to avoid the 'tipping points'. But I think that:
i. The capitalist market forces already strongly favouring renewables due to pure price competitiveness; and
ii. The kind of aggressive climate policies now implemented by the EU and some other OECD countries;

will be quite sufficient to avoid those tipping points in reasonable time, say 40 years. I think we already left the exponential growth of CO2, and that we are now in linear growth. In as little as 5-10 years I hypothesize that we will see flat CO2 growth.
...
and
...
I agree about 350 as a good goal.
I think we're getting out of CO2 growth pretty soon (5-10 years), and we will see a stable decline starting well before 2050.
In one post you indicate CO2 growth will be flat within 5-10 years.  I presume this means neither acceleration nor deceleration - if one year's increase is 1.0 ppm, the next year's increase is also 1.0 ppm.  (This is certainly an improvement on the current acceleration of CO2 growth.)

In the next post you indicate CO2 growth will end within 5-10 years.  I'm pretty sure this means we will have reached peak atmospheric CO2 concentrations.   (This would be good news indeed.)
...

All this is a bit speculative, but I do see some positive things happening. If we take Sweden as an example, our GHG emissions have been declining for 15 years already. Last year we had a 1.8% decline, in spite of strong economic growth.
Not enough, but we will have a larger decline in coming years, due to new policies being implemented and a lot of investments in renewables.
A few days ago we got really positive news from the EU, with aggressive new climate policies aiming for CO2 neutrality 2050. This covers several big OECD countries. I'm confident we will see these policies implemented, and that all of EU will see a growing decline in GHG emissions.

Looking at the Keeling curve, there are some signs that we already have left the exponential growth phase and entered a linear growth phase. Yes, I think we will see peak CO2 in less than 10 years. Strong declines in OECD countries will be paired with growth in developing countries, but the market forces will prevail and favour the renewables and causing disinvestment in FF.

Tor Bejnar

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2264 on: December 14, 2019, 06:37:35 PM »
Thanks
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nanning

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2265 on: December 14, 2019, 06:39:17 PM »
<snip>
How bad does the probability of forming a civilization on a random planet have to be for us to be alone, for us to be the only time in the entire history of the universe that there’s ever been a civilization? That number is 1 in 10 billion trillion.

That number tells me that the only way that we can be the only civilization in cosmic history is if the odds are that low or lower. As long as there’s a probability larger than that, then it has happened before. So unless nature is really perversely biased against forming civilizations then there have been others.

Thanks AbruptSLR. Interesting. Another example of 'civilisation bubble'. So I can try to point out the bubble and give another view.

Civilisation in general means lifeforms going bad, going for fantasies, going supreme, going insane, going for total destruction.
That goes for all exobiology lifeforms as well. There are no interstellar 'manned' spaceships.

Without supremacy over all other lifeforms and the thereby induced insanity, it is impossible to create high tech. In the very long term it is always impossible.


Perversely?
"What?" I say, I say "No no no, Supremacy is perverse. Not nature."

Nature is not 'biased' against anything. Perhaps you mean that living nature experiences a civilisation-induced mass extinction because it is biased against civilisation? ;)

This post is not meant as an attack. I think this is a very important but perhaps difficult to see subject.
I ask myself, why people want to live inside bubbles? "Come outside, the view's better here." "What's that? I didn't hear you." :)

We should've moved South.
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AbruptSLR

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2266 on: December 15, 2019, 10:41:11 PM »
For those not familiar with the history of supercomputers and climate models, I provide the following linked article that address some of the many different details of that story.  Also, I note that when the associated attached image indicates that many current climate models are accounting for ice sheet feedbacks they only mean MISI models not MICI models:

Title: "Supercomputers, Climate Models and 40 Years of the World Climate Research Programme"

https://insideclimatenews.org/news/06122019/climate-models-supercomputer-world-research-program-agu-100-anniversary-cheyenne-wyoming

Extract: "Earlier this week, a group of scientists published a peer-reviewed paper comparing the early climate models published between 1970 and the mid-2000s with what actually happened. They found that 14 of the 17 early models' projections about temperature change as emissions rise were almost indistinguishable from the observed record.

Today's computer models are far more complex, requiring supercomputers to account for everything from the forces melting Antarctica's ice to the impact of vegetation on temperature and moisture. But there are still uncertainties, such as how aerosols impact cloud formation that could affect temperature and how and when tipping points such as loss of sea ice or thawing of permafrost will trigger faster global changes.

The next generation models—running on even more powerful supercomputers—are being designed to incorporate more detail to help answer increasingly difficult questions."

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AbruptSLR

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2267 on: December 15, 2019, 10:47:34 PM »
...
Nature is not 'biased' against anything. Perhaps you mean that living nature experiences a civilisation-induced mass extinction because it is biased against civilisation? ;)

This post is not meant as an attack. I think this is a very important but perhaps difficult to see subject.


nanning,

While I appreciate that your post was not an attack, I note that the words that you quoted were not my words but those of the author of the cited article.  Furthermore, I note that virtually all of my posts are not intended to provide a definitive account for our extremely complex climate change situation; but rather they are intended to provide more pieces of this complex puzzle slowly bringing the reality of our current situation into focus by progressively reducing uncertainty.

Best,
ASLR
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AbruptSLR

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2268 on: December 15, 2019, 11:16:48 PM »
It appears to be more difficult for COP nations to agree to take effective climate action than some posts in this thread seem to indicate:

Title: "Major states snub calls for climate action as U.N. summit wraps up"

https://www.reuters.com/article/us-climate-change-accord/major-states-snub-calls-for-climate-action-as-un-summit-wraps-up-idUSKBN1YJ02D

Extract: "A handful of major states resisted pressure on Sunday to ramp up efforts to combat global warming as a U.N. climate summit ground to a close, angering smaller countries and a growing protest movement that is pushing for emergency action.

Brazil, China, Australia, Saudi Arabia and the United States had led resistance to bolder action, delegates said."
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2269 on: December 15, 2019, 11:39:17 PM »
The linked reference finds that: "Thus, models that have missed out on considering this contribution could have underestimated the extent of oxygen depletion we are to expect in a future, warming world. A more intense expansion of dead zones than expected could have severe ecological, economical (fisheries), and climatic consequences."

Sabine K. Lengger et al. (06 December 2019), "Dark carbon fixation in the Arabian Sea oxygen minimum zone contributes to sedimentary organic carbon (SOM)", Global Biogeochemical Cycles,
https://doi.org/10.1029/2019GB006282

https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019GB006282
&
https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1029/2019GB006282?referrer_access_token=3UzHv2eeWLjkTpg9Ct_HesOuACxIJX3yJRZRu4P4ervSH3IgF-dOHgRHvW_nefh_mVeJv0V8Lu-avjVuqLf9BaztwyUeIQyHDbsj8NTMHpfk6sEJw70Cpsa1nMtAsQ747bdsauNzv8Sg7eW8uv85xg%3D%3D

Abstract
In response to rising CO2 concentrations and increasing global sea surface temperatures, oxygen minimum zones (OMZ), or “dead zones”, are expected to expand. OMZs are fueled by high primary productivity, resulting in enhanced biological oxygen demand at depth, subsequent oxygen depletion, and attenuation of remineralization. This results in the deposition of organic carbon‐rich sediments. Carbon drawdown is estimated by biogeochemical models; however, a major process is ignored: carbon fixation in the mid‐ and lower water column. Here, we show that chemoautotrophic carbon fixation is important in the Arabian Sea OMZ; and manifests in a 13C‐depleted signature of sedimentary organic carbon. We determined the δ13C values of SOM deposited in close spatial proximity but over a steep bottom‐water oxygen gradient, and the δ13C composition of biomarkers of chemoautotrophic bacteria capable of anaerobic ammonia oxidation (anammox). Isotope mixing models show that detritus from anammox bacteria or other chemoautotrophs likely forms a substantial part of the organic matter deposited within the Arabian Sea OMZ (~17%), implying that the contribution of chemoautotrophs to settling organic matter is exported to the sediment. This has implications for the evaluation of past, and future, OMZs: biogeochemical models that operate on the assumption that all sinking organic matter is photosynthetically derived, without new addition of carbon, could significantly underestimate the extent of remineralization. Oxygen demand in oxygen minimum zones could thus be higher than projections suggest, leading to a more intense expansion of OMZs than expected.

Plain Language Summary

Oxygen minimum zones are areas in the ocean in which algae produce large amounts of organic material. When this sinks towards the seafloor, all oxygen at depth is used up. This results in vast “dead zones” where almost no oxygen is available to sustain life. With global warming, and increased nutrients from rivers, dead zones are forecast to expand. Computer models can calculate this, by considering algal production, and the amount of material delivered to the seafloor. However, these models often ignore a major process: anaerobic bacteria in the deeper water column, that can live at the edge or in the middle of these dead zones, which can also produce organic material from the dissolved CO2. In this study, we used the fact that these bacteria add a distinct signature to the organic material, to show that one fifth of the organic matter on the seafloor could stem from bacteria living in these dead zones. Thus, models that have missed out on considering this contribution could have underestimated the extent of oxygen depletion we are to expect in a future, warming world. A more intense expansion of dead zones than expected could have severe ecological, economical (fisheries), and climatic consequences.

See also:

Title: "We May Have Gravely Underestimated The Threat of 'Dead Zones' in The World's Oceans"

https://www.sciencealert.com/dead-zones-in-the-world-s-oceans-could-be-a-much-greater-threat-than-we-realised
« Last Edit: December 16, 2019, 03:34:36 AM by AbruptSLR »
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2270 on: December 16, 2019, 12:35:42 AM »
As an update to the linked article about this season's field work for the ITGC, I post the first image from Andreas T showing where the field team plans to drill through the Eastern Thwaites Ice Shelf (ETIS) to "... install instrumentation to measure the ocean, and use seismic and radar systems to map the ice thickness and the cavity beneath the ice. Teams will also collect sample sediment cores from the sub-ice seabed."  I presume that they are drilling at the base of the ETIS instead of at the base of the Thwaites Ice Tongue (see the second image) is due to safety associate with the risk that the ice tongue might surge downstream soon.

Also, I provide the third image which presents another perspective on the bed topology near the Thwaites Glacier gateway:

Title: "Land Ice Field Season 2019-2020, Antarctica"

https://thwaitesglacier.org/events/land-ice-field-season-2019-2020-antarctica

Extract: "MELT, TARSAN, GHC, THOR, and TIME teams will depart for McMurdo in early November 2019, and will deploy to the field between late November 2019 and January 2020.

ITGC teams plan to drill through the floating ice at the edge of the ice sheet, install instrumentation to measure the ocean, and use seismic and radar systems to map the ice thickness and the cavity beneath the ice. Teams will also collect sample sediment cores from the sub-ice seabed.  A geoscience team will collect rock samples from nearby mountains to examine the past history of the ice sheet. Farther upstream, another field team will investigate the boundary between the fast-flowing ice of Thwaites Glacier and the near-stationary ice next to it."

Edit: I provide the fourth image which is that same as the third image (of the Thwaites Gateway bed topology) except that it has a vertical scale.
« Last Edit: December 16, 2019, 04:28:06 PM by AbruptSLR »
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2271 on: December 16, 2019, 07:59:46 AM »
My apologies AbruptSLR for presenting that quote as yours  :-[. I guess I just hopped on the opportunity to post my bubble-breaking message and didn't read futher. I'll try to be more careful.

After the bad treatment by police of youth and indiginous protesters outside after they were excluded from meaningful U.N. talks, and the COP25 failure in a declared climate emergency, I was a bit agitated.

When in doubt, please be assured that I have much respect and gratitude for your unremitting informative science posts and views. I can be somewhat clumsy in my wordings but I love you.



Quote from: AbruptSLR
"virtually all of my posts are not intended to provide a definitive account for our extremely complex climate change situation; but rather they are intended to provide more pieces of this complex puzzle slowly bringing the reality of our current situation into focus by progressively reducing uncertainty."

Thanks again AbruptSLR.
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
   Simple: minimize your possessions and be free and kind    It's just a mindset.       Refugees welcome

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2272 on: December 16, 2019, 11:26:43 AM »
...
After the bad treatment by police of youth and indiginous protesters outside after they were excluded from meaningful U.N. talks, and the COP25 failure in a declared climate emergency, I was a bit agitated.



nanning,

I frequently get agitated myself by our current situation, but I find that I make more progress when I clear my head.

Best,
ASLR
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2273 on: December 16, 2019, 11:43:57 AM »
The linked reference finds that: "Thus, models that have missed out on considering this contribution could have underestimated the extent of oxygen depletion we are to expect in a future, warming world. A more intense expansion of dead zones than expected could have severe ecological, economical (fisheries), and climatic consequences."

Sabine K. Lengger et al. (06 December 2019), "Dark carbon fixation in the Arabian Sea oxygen minimum zone contributes to sedimentary organic carbon (SOM)", Global Biogeochemical Cycles,
https://doi.org/10.1029/2019GB006282

https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019GB006282


Per Kengger et al. (2019), the model projections cited below err on the side of least drama:

Title: "Ocean Deoxygenation"

https://www.iucn.org/theme/marine-and-polar/our-work/climate-change-and-oceans/ocean-deoxygenation

Extract: "Ocean deoxygenation is one of the most pernicious, yet under-reported side-effects of human-induced climate change. The primary causes of deoxygenation are eutrophication (increased nutrient run-off from land and sewage pollution) and nitrogen deposition from the burning of fossil fuels, coupled with the widespread impacts from ocean warming. Oxygen loss from warming has alarming consequences for global oceanic oxygen reserves, which have already been reduced by 2% over a period of just 50-years (from 1960 to 2010)."

&

Title: "Ocean deoxygenation : everyone's problem...summary for policy makers"

https://portals.iucn.org/library/node/48896

Extract: "Ocean model simulations project a further decline in the dissolved oxygen inventory of the global ocean of 1 to 7% by the year 2100, caused by a combination of warming-induced decline in oxygen solubility and temporal scales."
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2274 on: December 16, 2019, 11:54:07 AM »
The impacts of wildfires are also ready underestimated in climate models, and the linked article provides evidence for 2019 suggesting that the impacts of wildfires may well already be accelerating:

Title: "Staggering Video Shows How Much of Earth Was Actually on Fire in 2019"

https://www.sciencealert.com/this-alarming-video-shows-everywhere-the-world-was-burning-in-2019

Extract: "The data were pulled together and made available through an initiative called the Copernicus Atmosphere Monitoring Service (CAMS). It's organised by the European Centre for Medium-Range Weather Forecasts, and is designed to help governments and companies plan for wildfires and the resulting pollution.

"It has been an extremely busy year for CAMS regarding the monitoring of wildfires," says CAMS senior scientist Mark Parrington. "Throughout the year we have been closely watching the intensity of the fires and the smoke they emit all around the world and have experienced at times some quite exceptional fire activity."
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2275 on: December 16, 2019, 04:50:20 PM »
Per the linked article, Copernicus indicates that: "The twelve-month average temperature to November 2019 is 1.2°C above the level. The average for November 2019 alone is 1.3°C above the level."  Also, I note that currently GMSTA for the month of December is running warmer than November, so it is likely that GSMTA for 2019 may well be warmer than 1.2C above pre-industrial.

Title: "Surface air temperature for November 2019"

https://climate.copernicus.eu/surface-air-temperature-november-2019

Extract: "Averaging over twelve-month periods smooths out the shorter-term variations. Globally, the twelve-month period from December 2018 to November 2019 was 0.58°C warmer than the 1981-2010 average. The warmest twelve-month period was from October 2015 to September 2016, with a temperature 0.66°C above average. 2016 is the warmest calendar year on record, with a global temperature 0.63°C above that for 1981-2010. The second warmest calendar year, 2017, had a temperature 0.54°C above average, while the third warmest year, 2018, was 0.46°C above the 1981-2010 average.

0.63°C should be added to these values to relate recent global temperatures to the pre-industrial level defined in the IPCC Special Report on “Global Warming of 1.5°C”. The twelve-month average temperature to November 2019 is 1.2°C above the level. The average for November 2019 alone is 1.3°C above the level."
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2276 on: December 16, 2019, 05:32:34 PM »
The linked perspective piece suggests that in order to stop climate change, the global society needs to not only get to zero carbon emissions soon, but also to stop using carbon altogether:

Bernstein, S., Hoffmann, M. Climate politics, metaphors and the fractal carbon trap. Nat. Clim. Chang. 9, 919–925 (2019) doi:10.1038/s41558-019-0618-2

https://www.nature.com/articles/s41558-019-0618-2

Abstract: "The international community has treated climate change as an emissions reduction challenge, drawing on the analytical metaphor of the global commons, and thus the politics of collective action and international cooperation. So far, these strategies have failed to produce an effective global response. We propose decarbonization as the defining challenge and a new guiding metaphor for the problem structure: the global fractal. This metaphor aptly describes the decarbonization challenge, capturing the multilevel and interdependent nature of carbon lock-in and the fractal carbon trap facing decarbonization efforts. It also provides a means to explore the range of diverse policies and practices that can potentially escape the fractal carbon trap and catalyse deep decarbonization."

See also:

Title: "Halting climate change means a world without fossil fuels—not merely curbing emissions"

https://phys.org/news/2019-12-halting-climate-world-fossil-fuelsnot.html

Extract: ""Focusing only on emissions reductions can potentially miss—and mischaracterize—the more important challenge of decarbonization," says Matthew Hoffmann, a professor of political science at U of T Scarborough who co-authored the study.

"We need a new way to think about the decarbonization challenge and a new means to explore policies and practices that can begin deep, meaningful decarbonization efforts.""
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2277 on: December 16, 2019, 07:14:30 PM »
Quote
stop using carbon altogether
So much for eating anything ever again!
Quote
There are 6 elements found in almost all foods. These elements are carbon, hydrogen, nitrogen, phosphorus, and sulfur.
from https://thallchemhonors.weebly.com/elements-found-in-food.html

Per the quoted ban, canibalism is out, too:
Quote
We're each about 18 percent carbon by weight. If the average human weight is around 120 pounds—that's the Explainer's very rough estimate, encompassing both children and adults—there are about 21.6 pounds of carbon stored in the average person.
from Slate

Oh, that's not what ASLR's links meant ...   :D :D :D
Arctic ice is healthy for children and other living things.

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2278 on: December 16, 2019, 07:47:01 PM »
...
Oh, that's not what ASLR's links meant ...   :D :D :D

I was thinking of changing the articles recommendations to recommend that all coal, oil and gas (fossil fuels/feedstock) production/extraction should be stopped, but I didn't want to put words in the authors' mouths.  ;)
« Last Edit: December 16, 2019, 08:11:13 PM by AbruptSLR »
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2279 on: December 16, 2019, 08:08:25 PM »
As an update to the linked article about this season's field work for the ITGC, I post the first image from Andreas T showing where the field team plans to drill through the Eastern Thwaites Ice Shelf (ETIS) to "... install instrumentation to measure the ocean, and use seismic and radar systems to map the ice thickness and the cavity beneath the ice. Teams will also collect sample sediment cores from the sub-ice seabed."  I presume that they are drilling at the base of the ETIS instead of at the base of the Thwaites Ice Tongue (see the second image) is due to safety associate with the risk that the ice tongue might surge downstream soon.


Here is a photo of the drilling site for downstream of the grounding zone from Dec. 14, 2019.  Hopefully, they will learn about the tidal amplification driving the current subglacial cavity expansion due to warm modified CDW.
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2280 on: December 16, 2019, 09:10:52 PM »
As we have seen in Replies #2132 & #2160 , Hausfather et al. (2019) demonstrated that many historical climate model projections of GMSTA show a good correlation with the observed record, when correcting the projections for the assumed radiative forcing.  Unfortunately, these projections did not account for most ice-climate (ice sheet) feedback mechanisms so while these historical GMSTA projection may have demonstrated skill so far, they will likely exhibit a lower skill level if/when ice sheet mass loss increases nonlinearly.  While sea level rise, SLR, projections are influenced by other factors beside ice sheet mass loss (such as: water from land, mountain glacier mass loss and thermal expansion), it is possible that sometime after 2040 ice sheet mass loss contributions may dominate SLR.  While the linked 2017 article discusses reasoning for why the SLR projections from FAR to SAR to TAR to AR4 to AR5 have changed, it only mentions the possible significance of accelerating ice sheet mass loss in passing.  Furthermore, I strongly suspect that AR6 will have higher SLR projections than any of the earlier five AR projections; and that AR7 will have higher SLR projections than AR6.  Only time will tell what actually happens, but I suspect that rationalizations (which downplay the risks of nonlinear increases in ice sheet mass loss in coming decades) of IPCC SLR projections such as those presented in the linked article have slowed the implementation of action to effectively fight climate change:

Title: "How good were the old forecasts of sea level rise?", by Clint Conrad - edited by Grace Shephard September 13, 2017

https://blogs.egu.eu/divisions/gd/2017/09/13/modern-day-sea-level-rise/

Extract: "I plotted the sea level projections of the five reports that the IPCC has released between 1990 and 2013 (Figure 2). Indeed, the 1990 report predicted slightly higher sea level for the year 2100 (31-110 cm higher) than did the most recent report from 2013 (28-98 cm higher). In fact, the IPCC projections for 2100 sea level declined from 1990 through 2007, until they increased again in the most recent report in 2013 (Figure 2). Why is this? Well, we have nearly 3 decades of observations that could help us to answer this question!

I have plotted (Figure 3) the 1990 report’s sea level projection from 1990-2100 (Fig. 9.6 of that report) along with actual sea level observations made using satellite altimetry between 1992 and 2016, which have been nicely compiled by the University of Colorado’s Sea Level Research Group. The comparison shows (Figure 3) that the actual sea level change for the past 24 years has fallen slightly below the “best” estimate of the 1990 report, and well above the “low” estimate.

Thus, the IPCC’s 1990 sea level projection did a remarkably good job for the first three decades of its prediction timetable, and the next 8 decades don’t seem so unreasonable as a result. What did the 1990 report do right? Here the 1990 IPCC report helps us again, by breaking down its projection into contributions from four factors: thermal expansion of the seawater due to warming, the melting of mountain glaciers, and changes in the mass of the great ice sheets in Greenland and Antarctica. The 1990 report makes predictions for the changes in sea level caused by these factors for a 45-year timeframe of 1985-2030, and I have plotted these predictions as a rate (in mm/yr) in Figure 4. Thermal expansion and deglaciation in mountainous areas were predicted to be the largest contributors. Greenland was predicted to contribute only slightly, and Antarctica was predicted to gain ice, resulting in a drop in sea level.

Thus, in 2010 the predicted rates of sea level rise from two factors (thermal expansion and mountain glaciers) had not yet reached the 2030 predictions of the 1990 report, but the contributions from Greenland, Antarctica, and land water loss have already nearly met or exceeded the predictions of 1990. Indeed, recent satellite observations between 2002 and 2014 show an acceleration of melting in Antarctica (Harig et al., 2015) and especially in Greenland (Harig et al., 2016). The recognition that Antarctica and Greenland may contribute significantly more to sea level rise in the future compared to earlier estimates is reflected in the 2013 IPCC report (Figure 2)."
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2281 on: December 16, 2019, 11:17:50 PM »
While Michael Mann emphasizes the potentially positive side of his (& his co-author's) work on quasi-resonant amplification; his/their work also raises the specter that Arctic Amplification may increase faster than previously assumed (depending on the assumptions that one makes about the future):

Title: "Climate Change and Extreme Summer Weather Events – The Future is still in Our Hands"

http://www.realclimate.org/index.php/archives/2018/10/climate-change-and-extreme-summer-weather-events-the-future-is-still-in-our-hands/

Extract: "Something else happens in addition during summer, when the poleward temperature contrast is especially weak. The atmosphere can behave like a “wave guide”, trapping the shorter wavelength Rossby waves (those that that can fit 6 to 8 full wavelengths in a complete circuit around the Northern Hemisphere) to a relatively narrow range of latitudes centered in the mid-latitudes, preventing them from radiating energy away toward lower and higher latitudes. That allows the generally weak disturbances in this wavelength range to intensify through the physical process of resonance, yielding very large peaks and troughs at the sub-continental scale, i.e. unusually extreme regional weather anomalies.

The increase in the frequency of these events over time is seen to coincide with an index of Arctic amplification (the difference between warming in the Arctic and the rest of the Northern Hemisphere), suggestive of a connection (see Figure below).

See also:

Michael E. Mann et al (31 Oct 2018), "Projected changes in persistent extreme summer weather events: The role of quasi-resonant amplification", Science Advances, Vol. 4, no. 10, eaat3272, DOI: 10.1126/sciadv.aat3272

http://advances.sciencemag.org/content/4/10/eaat3272

Abstract: "Persistent episodes of extreme weather in the Northern Hemisphere summer have been associated with high-amplitude quasi-stationary atmospheric Rossby waves, with zonal wave numbers 6 to 8 resulting from the phenomenon of quasi-resonant amplification (QRA). A fingerprint for the occurrence of QRA can be defined in terms of the zonally averaged surface temperature field. Examining state-of-the-art [Coupled Model Intercomparison Project Phase 5 (CMIP5)] climate model projections, we find that QRA events are likely to increase by ~50% this century under business-as-usual carbon emissions, but there is considerable variation among climate models. Some predict a near tripling of QRA events by the end of the century, while others predict a potential decrease. Models with amplified Arctic warming yield the most pronounced increase in QRA events. The projections are strongly dependent on assumptions regarding the nature of changes in radiative forcing associated with anthropogenic aerosols over the next century. One implication of our findings is that a reduction in midlatitude aerosol loading could actually lead to Arctic de-amplification this century, ameliorating potential increases in persistent extreme weather events."

&

Mann et al (2017), "Influence of Anthropogenic Climate Change on Planetary Wave Resonance and Extreme Weather Events", Scientific Reports 7, No. 45242, doi: https//doi.org/10.1038/srep45242

https://www.nature.com/articles/srep45242
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2282 on: December 16, 2019, 11:21:33 PM »
The linked reference indicates that climate models need to account for the geographic distribution of anthropogenic aerosol emissions in order to correctly simulate the associated radiative forcing impacts on global warming:

Geeta G. Persad & Ken Caldeira (2018), "Divergent global-scale temperature effects from identical aerosols emitted in different regions", Nature Communications, volume 9, Article number: 3289, DOI: https://doi.org/10.1038/s41467-018-05838-6

https://www.nature.com/articles/s41467-018-05838-6

Abstract: "The distribution of anthropogenic aerosols’ climate effects depends on the geographic distribution of the aerosols themselves. Yet many scientific and policy discussions ignore the role of emission location when evaluating aerosols’ climate impacts. Here, we present new climate model results demonstrating divergent climate responses to a fixed amount and composition of aerosol—emulating China’s present-day emissions—emitted from 8 key geopolitical regions. The aerosols’ global-mean cooling effect is fourteen times greater when emitted from the highest impact emitting region (Western Europe) than from the lowest (India). Further, radiative forcing, a widely used climate response proxy, fails as an effective predictor of global-mean cooling for national-scale aerosol emissions in our simulations; global-mean forcing-to-cooling efficacy differs fivefold depending on emitting region. This suggests that climate accounting should differentiate between aerosols emitted from different countries and that aerosol emissions’ evolving geographic distribution will impact the global-scale magnitude and spatial distribution of climate change."
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2283 on: December 16, 2019, 11:23:04 PM »
The linked reference provides evidence that CMIP5 model projections 'have underestimated the cooling effect that aerosol particles have had on climate in recent decades"; which 'suggests that the models are not sensitive enough to increasing greenhouse gas concentrations in the atmosphere'.  In other words, this reference finds that the CMIP5 models (as a group) underestimated both TCR & ECS:

Trude Storelvmo et al. (29 August 2018), "Lethargic response to aerosol emissions in current climate models", Geophysical Research Letters, https://doi.org/10.1029/2018GL078298

https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2018GL078298

Abstract
The global temperature trend observed over the last century is largely the result of two opposing effects – cooling from aerosol particles and greenhouse gas (GHG) warming. While the effect of increasing GHG concentrations on Earth's radiation budget is well‐constrained, that due to anthropogenic aerosols is not, partly due to a lack of observations. However, long‐term surface measurements of changes in downward solar radiation (SDSR), an often‐used proxy for aerosol radiative impact, are available worldwide over the last half‐century. We compare SDSR changes from ∼1,400 stations to those from the CMIP5 global climate simulations over the period 1961‐2005. The observed SDSR shows a strong early downward trend followed by a weaker trend‐reversal, broadly consistent with historical aerosol emissions. However, despite considerable changes to known aerosol emissions over time, the models show negligible SDSR trends, revealing a lethargic response to aerosol emissions, and casting doubt on the accuracy of their future climate projections.

Plain Language Summary

Observations of incoming solar radiation, as measured at approximately 1400 surface stations worldwide, show a strong downward trend from the 1960s to the 1980s, followed by a weaker trend reversal thereafter. These trends are thought to be due to changes in the amount of aerosol particles in the atmosphere, and we find support for that here in the temporal evolution of anthropogenic aerosol emissions. This is expected because aerosol particles reflect and/or absorb sunlight back to space, and have a net cooling effect on Earth's climate. However, we find that the current generation of climate models simulate negligible solar radiation trends over the last half‐century, suggesting that they have underestimated the cooling effect that aerosol particles have had on climate in recent decades. Despite this, climate models tend to reproduce surface air temperature over the time period in question reasonably well. This, in turn, suggests that the models are not sensitive enough to increasing greenhouse gas concentrations in the atmosphere, with important implications for their ability to simulate future climate.
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2284 on: December 16, 2019, 11:29:10 PM »
The linked reference indicates increases in GMSTA of between 0.5 to 1.1C due to expected reductions in anthropogenic aerosols this century.

B. H. Samset, M. Sand, C. J. Smith, S. E. Bauer, P. M. Forster, J. S. Fuglestvedt, S. Osprey & C.-F. Schleussner (24 January 2018), "Climate Impacts From a Removal of Anthropogenic Aerosol Emissions", Geophysical Research Letters, DOI: 10.1002/2017GL076079

http://onlinelibrary.wiley.com/doi/10.1002/2017GL076079/full

Abstract: "Limiting global warming to 1.5 or 2.0°C requires strong mitigation of anthropogenic greenhouse gas (GHG) emissions. Concurrently, emissions of anthropogenic aerosols will decline, due to coemission with GHG, and measures to improve air quality. However, the combined climate effect of GHG and aerosol emissions over the industrial era is poorly constrained. Here we show the climate impacts from removing present-day anthropogenic aerosol emissions and compare them to the impacts from moderate GHG-dominated global warming. Removing aerosols induces a global mean surface heating of 0.5–1.1°C, and precipitation increase of 2.0–4.6%. Extreme weather indices also increase. We find a higher sensitivity of extreme events to aerosol reductions, per degree of surface warming, in particular over the major aerosol emission regions. Under near-term warming, we find that regional climate change will depend strongly on the balance between aerosol and GHG forcing."
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2285 on: December 16, 2019, 11:48:19 PM »
The linked reference on structured expert judgment of ice sheet contributions to future SLR, states: "We find that a global total SLR exceeding 2 m by 2100 lies within the 90% uncertainty bounds for a high emission scenario. This is more than twice the upper value put forward by the Intergovernmental Panel on Climate Change in the Fifth Assessment Report."

Jonathan L. Bamber, Michael Oppenheimer, Robert E. Kopp, Willy P. Aspinall, and Roger M. Cooke (June 4, 2019, first published May 20, 2019), "Ice sheet contributions to future sea-level rise from structured expert judgment", PNAS, 116 (23), 11195-11200; https://doi.org/10.1073/pnas.1817205116

https://www.pnas.org/content/116/23/11195

Significance
Future sea level rise (SLR) poses serious threats to the viability of coastal communities, but continues to be challenging to project using deterministic modeling approaches. Nonetheless, adaptation strategies urgently require quantification of future SLR uncertainties, particularly upper-end estimates. Structured expert judgement (SEJ) has proved a valuable approach for similar problems. Our findings, using SEJ, produce probability distributions with long upper tails that are influenced by interdependencies between processes and ice sheets. We find that a global total SLR exceeding 2 m by 2100 lies within the 90% uncertainty bounds for a high emission scenario. This is more than twice the upper value put forward by the Intergovernmental Panel on Climate Change in the Fifth Assessment Report.

Abstract

Despite considerable advances in process understanding, numerical modeling, and the observational record of ice sheet contributions to global mean sea-level rise (SLR) since the Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change, severe limitations remain in the predictive capability of ice sheet models. As a consequence, the potential contributions of ice sheets remain the largest source of uncertainty in projecting future SLR. Here, we report the findings of a structured expert judgement study, using unique techniques for modeling correlations between inter- and intra-ice sheet processes and their tail dependences. We find that since the AR5, expert uncertainty has grown, in particular because of uncertain ice dynamic effects. For a +2 °C temperature scenario consistent with the Paris Agreement, we obtain a median estimate of a 26 cm SLR contribution by 2100, with a 95th percentile value of 81 cm. For a +5 °C temperature scenario more consistent with unchecked emissions growth, the corresponding values are 51 and 178 cm, respectively. Inclusion of thermal expansion and glacier contributions results in a global total SLR estimate that exceeds 2 m at the 95th percentile. Our findings support the use of scenarios of 21st century global total SLR exceeding 2 m for planning purposes. Beyond 2100, uncertainty and projected SLR increase rapidly. The 95th percentile ice sheet contribution by 2200, for the +5 °C scenario, is 7.5 m as a result of instabilities coming into play in both West and East Antarctica. Introducing process correlations and tail dependences increases estimates by roughly 15%.
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2286 on: December 16, 2019, 11:52:06 PM »
The linked reference provides evidence that CMIP5 model projections 'have underestimated the cooling effect that aerosol particles have had on climate in recent decades"; which 'suggests that the models are not sensitive enough to increasing greenhouse gas concentrations in the atmosphere'.  In other words, this reference finds that the CMIP5 models (as a group) underestimated both TCR & ECS:

Trude Storelvmo et al. (29 August 2018), "Lethargic response to aerosol emissions in current climate models", Geophysical Research Letters, https://doi.org/10.1029/2018GL078298

https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2018GL078298

Abstract
The global temperature trend observed over the last century is largely the result of two opposing effects – cooling from aerosol particles and greenhouse gas (GHG) warming. While the effect of increasing GHG concentrations on Earth's radiation budget is well‐constrained, that due to anthropogenic aerosols is not, partly due to a lack of observations. However, long‐term surface measurements of changes in downward solar radiation (SDSR), an often‐used proxy for aerosol radiative impact, are available worldwide over the last half‐century. We compare SDSR changes from ∼1,400 stations to those from the CMIP5 global climate simulations over the period 1961‐2005. The observed SDSR shows a strong early downward trend followed by a weaker trend‐reversal, broadly consistent with historical aerosol emissions. However, despite considerable changes to known aerosol emissions over time, the models show negligible SDSR trends, revealing a lethargic response to aerosol emissions, and casting doubt on the accuracy of their future climate projections.

Plain Language Summary

Observations of incoming solar radiation, as measured at approximately 1400 surface stations worldwide, show a strong downward trend from the 1960s to the 1980s, followed by a weaker trend reversal thereafter. These trends are thought to be due to changes in the amount of aerosol particles in the atmosphere, and we find support for that here in the temporal evolution of anthropogenic aerosol emissions. This is expected because aerosol particles reflect and/or absorb sunlight back to space, and have a net cooling effect on Earth's climate. However, we find that the current generation of climate models simulate negligible solar radiation trends over the last half‐century, suggesting that they have underestimated the cooling effect that aerosol particles have had on climate in recent decades. Despite this, climate models tend to reproduce surface air temperature over the time period in question reasonably well. This, in turn, suggests that the models are not sensitive enough to increasing greenhouse gas concentrations in the atmosphere, with important implications for their ability to simulate future climate.

Compensatary error - amazing.
There is a principle which is a bar against all information, which cannot fail to keep a man in everlasting ignorance. That principle is contempt prior to investigation. - Herbert Spencer

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2287 on: December 17, 2019, 03:28:10 AM »
The linked pdf presents a good review paper about the mathematics of dynamic/nonlinear climate change; however, it does not explain how to incorporate the risks of ice-climate feedback mechanism into such mathematics:

Title: "The Physics of Climate Variability and Climate Change" by Michael Ghil (2019)

https://arxiv.org/pdf/1910.00583.pdf

Abstract: "The climate system is a forced, dissipative, nonlinear, complex and heterogeneous system that is out of thermodynamic equilibrium. The system exhibits natural variability on many scales of motion, in time as well as space, and it is subject to various external forcings, natural as well as anthropogenic. This paper reviews the observational evidence on climate phenomena and the governing equations of planetary-scale flow, as well as presenting the key concept of a hierarchy of models as used in the climate sciences. Recent advances in the application of dynamical systems theory, on the one hand, and of nonequilibrium statistical physics, on the other, are brought together for the first time and shown to complement each other in helping understand and predict the system’s behavior. These complementary points of view permit a self-consistent handling of subgrid-scale phenomena as stochastic processes, as well as a unified handling of natural climate variability and forced climate change, along with a treatment of the crucial issues of climate sensitivity, response, and predictability."
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2288 on: December 17, 2019, 07:02:04 PM »
The Earth's magnetic pole has recently been drifting so fast that the World Magnetic Model 2020 (WMM2020) projections (see images) had to be updated and released early.  However, the projections ignore the risk that ice sheet mass loss may be associated with this recent increase in the rate of drift, and so the model projects that the rate of drift will soon slow down.  Thus, I will not be surprised if the WMM2025 projections have to updated and released well before 2025:

Title: "World Magnetic Model 2020 Released" released Dec 10, 2019.

https://www.ncei.noaa.gov/news/world-magnetic-model-2020-released

Extract: "A new and updated version of the WMM is released every five years. The latest WMM2020 model will extend to 2025.

The WMM2020 forecasts that the northern magnetic pole will continue drifting toward Russia, although at a slowly decreasing speed—down to about 40 km per year compared to the average speed of 55 km over the past twenty years."

See also:

Title: "The World Magnetic Model"

https://www.ngdc.noaa.gov/geomag/WMM/
https://www.ngdc.noaa.gov/geomag/WMM/soft.shtml#downloads

Extract: "12/10/2019: WMM2020 Release
The full release of the WMM (WMM2020) is now available. All WMM products and services have been updated."

&

Title: "Earth's Magnetic North Pole Continues Drifting, Crosses Prime Meridian"

https://www.livescience.com/earth-magnetic-north-passes-prime-meridian.html

Extract: "Earth's magnetic north pole, which has been wandering faster than expected in recent years, has now crossed the prime meridian."
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2289 on: December 17, 2019, 07:57:57 PM »
Some posters in this thread have expressed surprise that I have been able to provide so many peer reviewed references indicating that consensus climate science prior to the release of AR5 have erred on the side of least drama (ESLD) so many different ways.  However, as an engineer I am amazed that the public has been exposed to so little discuss about climate risks and public safety.  In this regard, I note that even if/when AR6, AR7 and/or AR8 finally address many/most of the technical short-comings of earlier consensus climate projections the general public will likely still not understand the risk that has been transferred to them by those with much more power.  While the topic of risk assessment is too complex to address in this post, nevertheless I provide the following examples of risk that the general public likely misunderstands.

The first image shows how currently the partial load and resistance safety approach is applied to safeguard the public.  This image shows how for each load pdf a relevant partial load factor is applied to increase the partial design load, and that for each capacity pdf a relevant partial capacity factor is applied to decrease the partial design capacity and any acceptable design must maintain at a probability of failure below the acceptable level for the given design limit state.  Currently, policy makers are shifting criteria for much of our infrastructure to resiliency limit states where failure is allowed, on the assumption that the general public is tough enough to take some abuse before collapsing.  In this image note that load pdf is assumed to be un-skewed.

The second image shows that as one accepts the reality of more and more positive climate feedback mechanisms that the pdf for climate sensitivity becomes more and more right-skewed and I note that if this image considered ice sheet forcing mechanisms the ECS pdf would be even more right-skewed and fat-tailed.

The third image shows that for right-skewed load probability density functions (the image shows the case for right-skewed wind gust loading for an aircraft design) it is rather complicated (& thus is not commonly used for evaluating infrastructure to keep the public safe) to calculate the probability of failure (or as shown the related reliability probability)  and that for an acceptable design the capacity pdf has to engineered to be far to the right.  Furthermore, as the right-skewed climate sensitivity pdf is used for determining likely climate change consequences and as there is only one Earth one would assume that decision makers would maintain an adequate factor of safety against the risk of a cascade of Earth System tipping points, but they do not.

Lastly, the fourth image illustrates the concept of lifetime factor of safety to account for system deterioration with time.  If this reliability concept were to be applied to climate change one would need to evaluate how the deterioration of various Earth Systems (like permafrost, etc.) decreases system reliability with time thus progressively increasing our joint risk as GMSTA increases (a concept that is not adequately conveyed to the public by the Carbon Budget approach).


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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2290 on: December 17, 2019, 08:28:11 PM »
The linked pdf presents a good review paper about the mathematics of dynamic/nonlinear climate change; however, it does not explain how to incorporate the risks of ice-climate feedback mechanism into such mathematics:

Title: "The Physics of Climate Variability and Climate Change" by Michael Ghil (2019)

https://arxiv.org/pdf/1910.00583.pdf

Abstract: "The climate system is a forced, dissipative, nonlinear, complex and heterogeneous system that is out of thermodynamic equilibrium. The system exhibits natural variability on many scales of motion, in time as well as space, and it is subject to various external forcings, natural as well as anthropogenic. This paper reviews the observational evidence on climate phenomena and the governing equations of planetary-scale flow, as well as presenting the key concept of a hierarchy of models as used in the climate sciences. Recent advances in the application of dynamical systems theory, on the one hand, and of nonequilibrium statistical physics, on the other, are brought together for the first time and shown to complement each other in helping understand and predict the system’s behavior. These complementary points of view permit a self-consistent handling of subgrid-scale phenomena as stochastic processes, as well as a unified handling of natural climate variability and forced climate change, along with a treatment of the crucial issues of climate sensitivity, response, and predictability."

What a truly fascinating paper! Thank you ASLR.

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2291 on: December 17, 2019, 09:01:49 PM »
Some posters in this thread have expressed surprise that I have been able to provide so many peer reviewed references indicating that consensus climate science prior to the release of AR5 have erred on the side of least drama (ESLD) so many different ways.  However, as an engineer I am amazed that the public has been exposed to so little discuss about climate risks and public safety.  In this regard, I note that even if/when AR6, AR7 and/or AR8 finally address many/most of the technical short-comings of earlier consensus climate projections the general public will likely still not understand the risk that has been transferred to them by those with much more power.  While the topic of risk assessment is too complex to address in this post, nevertheless I provide the following examples of risk that the general public likely misunderstands.

The first image shows how currently the partial load and resistance safety approach is applied to safeguard the public.  This image shows how for each load pdf a relevant partial load factor is applied to increase the partial design load, and that for each capacity pdf a relevant partial capacity factor is applied to decrease the partial design capacity and any acceptable design must maintain at a probability of failure below the acceptable level for the given design limit state.  Currently, policy makers are shifting criteria for much of our infrastructure to resiliency limit states where failure is allowed, on the assumption that the general public is tough enough to take some abuse before collapsing.  In this image note that load pdf is assumed to be un-skewed.

The second image shows that as one accepts the reality of more and more positive climate feedback mechanisms that the pdf for climate sensitivity becomes more and more right-skewed and I note that if this image considered ice sheet forcing mechanisms the ECS pdf would be even more right-skewed and fat-tailed.

The third image shows that for right-skewed load probability density functions (the image shows the case for right-skewed wind gust loading for an aircraft design) it is rather complicated (& thus is not commonly used for evaluating infrastructure to keep the public safe) to calculate the probability of failure (or as shown the related reliability probability)  and that for an acceptable design the capacity pdf has to engineered to be far to the right.  Furthermore, as the right-skewed climate sensitivity pdf is used for determining likely climate change consequences and as there is only one Earth one would assume that decision makers would maintain an adequate factor of safety against the risk of a cascade of Earth System tipping points, but they do not.

Lastly, the fourth image illustrates the concept of lifetime factor of safety to account for system deterioration with time.  If this reliability concept were to be applied to climate change one would need to evaluate how the deterioration of various Earth Systems (like permafrost, etc.) decreases system reliability with time thus progressively increasing our joint risk as GMSTA increases (a concept that is not adequately conveyed to the public by the Carbon Budget approach).

ASLR,

As an engineer I am not at all surprised. We engineers truly think differently. For us, facts and technical analysis like these have tangible reality and extreme importance. Understanding risks requires understanding all of these things and more.

For the lay person, the process isn't just different, it is fundamentally different. The facts as we would know them have little to do with their analysis, reasoning or response. Rhetorical arguments, and more importantly emotional arguments have the largest sway. They are completely unable to understand, let alone evaluate, the technical merits of the analyses or even of the underlying data and facts. Theirs is not an analysis of what is happening in real terms. Theirs is analysis of trust of those speaking based on other factors. Someone speaking definitely and confidently (regardless of the merits of their speech) is assessed as more credible. Someone speaking emotionally and powerfully is assigned either greater or lesser credibility based on the character of that emotion, the degree to which they are able to engage the listeners mirror neuron network, and the degree to which the speech and emotion matches the existing state of the listener. I.e. is it supportive of what they already believe or desire.

What they already believe is highly dependent on what is beneficial to them in their near term environment, and in terms of their desires.

Conversely, if the speaker can strongly engage the mirror neuron network to get past the persons filters, they become viewed as an ally and someone to trust. Once there, the speaker can engender strong fears which the listener will take on as their own. Fear is a powerful driver. It speaks to personal physical safety, or lack of safety. That drives action to minimize the things causing the fear. But none of that need be based on reality. Neither does it even have to align in any way with reality and truth. It can and often is direct opposed to objective reality and truth.

The papers you have posted have been and continue to be an amazing summary of the state of our current knowledge of the physical world, of the path we are now on, and of the potentials for where that takes the Earth's systems, and with them - us.

The picture is terrifying. We still have fundamental uncertainties about precisely where the points of no return are. But what is clear is that knowing that will not matter. Humanity has chosen to push beyond those limits and to only respond AFTER it is clear that we have entered thermal run away to a different stable state for the Earth. We humans do respond to direct palpable information. We do not generally (with exceptions) respond to reason or reasoning. We are really bad at using precautionary principles, safety bounds and margins, or any related ideas. We are particularly terrible at those when there are countering forces, such as near term gain or emotional desires, wishes, dreams, conceptions, and preconceptions involved. All of those are involved here.

As a result, we will push the Earth beyond the points of no return. We will collectivley wail and scream about how horrible it is and about how someone else should have done something. By then it will of course be far too late to do anything. All of the emotional responses are rendered meaningless drivel. Worse, they will likely engender actions that are counter productive to where we find ourselves.

One example of billions of that.... When the cod fisheries were collapsing on the great bank, then President Reagan responded by supporting the fishermen buying and building bigger and better boats with better equipment to catch more fish to maintain their lifestyle and their catch. That of course accelerated the destruction of the ecosystem and the evolutionary response to fish becomming smaller than the nets could catch, and smaller than were economically viable. This only stopped when there were simply no more fish to catch. At no point were those in charge or involved able or willing to recognize the right answer. They had to not just dramatically reduce the catch to allow the stocks to recover, they had to stop fishing for them entirely. Instead they chose precisely the opposite action and destroyed the ecosystem, and with it any potential of returning to "normal" in anyones lifetime.

We face the same fate here. We humans are responding in exactly the same fashion in a myriad of different decisions and ways.

Rather than recognize the catastrophe we are in and doing what is required to save ourselves, the current leadership in the US (and several other countries) is making decisions that not only ignore that reality, but rather instead drive in exactly the wrong direction. Just as with the great banks cod, the result will be an acceleration of the shifts and a magnification of the catastrophe both in scope, size, and speed.

Whereas 20 years ago I thought we could avert what was coming, I have come to realize now that what I thought I knew then was wholly insufficient, and that our last real chance to avert major shifts in the environment likely passed in about 1970 - fifty years ago. Likewise, I recognize that we still lack understanding of major aspects needed for where we truly are and how fast and severe the shifts will be.

I now fully expect that climate change (through its subsidiary catastrophes on economy, finance, health, etc...) will likely play a major and possibly deciding role in when and how I personally will die. I am no spring chicken. For the young the situation is far more dire. For them other aspects like war, pestilence, disease and economic and ecological collapse are likely deciding factors in their demise.

And still - humanity will not listen, at least not until it is far far too late to do anything meaningful.

Sam

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2292 on: December 17, 2019, 09:35:49 PM »

Theirs is not an analysis of what is happening in real terms. Theirs is analysis of trust of those speaking based on other factors. Someone speaking definitely and confidently (regardless of the merits of their speech) is assessed as more credible.


Probably those who speak confidently that the general public put their trust in do so because they mistakenly think that they have solved the right-skewed (fat-tailed) ECS pdf by creating hardened luxury retreats for themselves if/when climate consequences come home to roost.  Unfortunately, there will not be enough room to harbor the general public in such hardened shelter when that time comes:

Title: "A cinema, a pool, a bar: inside the post-apocalyptic underground future"

https://www.theguardian.com/cities/2019/dec/16/a-cinema-a-pool-a-bar-inside-the-post-apocalyptic-underground-future

Extract: "A missile silo converted into a 15-storey luxury subterranean apartment complex could be a taste of what lies in store in cities around the world

Hall says 75 individuals can survive inside the sealed, self-sufficient converted silo for up to five years during social, political or environmental instability – even total collapse. When the crisis passes, silo residents expect to be able to emerge into the post-apocalyptic world to rebuild."

Edit: When I say: "Probably those who speak confidently that the general public put their trust in do so because they mistakenly think …", I mean that they are mistaken because by the time that these few emerge from their shelters climate change impacts will only be worse as it will take millennia for the GHGs in the atmosphere to dissipate.  Thus, these powerful few would do better to learn from the Bushmen how to live in the Kalahari desert rather than on planning to hide in a spider-hole like Saddam Hussein.
« Last Edit: December 17, 2019, 10:25:52 PM by AbruptSLR »
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2293 on: December 17, 2019, 09:43:33 PM »
The linked article indicates that methane emissions from the U.S. oil and gas sector are about 60% higher than EPA authorities acknowledge due to the neglected contributions from super emitter gas well blowouts.  It time to update consensus science anthropogenic methane emission scenarios to reflect this hazard particularly as U.S. oil and gas companies are currently busy exporting their hydrofracturing technology to produce more high-risk natural gas wells around the world.

Title: "Satellite uncovers Ohio gas well blowout's massive methane leak"

https://www.axios.com/satellite-uncovers-ohio-gas-blast-huge-methane-leak-0d42c47a-5711-47ea-bb96-de67a47ebc5c.html

Extract: "The EDF revealed last year that studies it had organize by EDF over five years found emissions from the U.S. oil and gas sector were 60% higher than Environmental Protection Authority estimates.

"Research has also shown that large, unpredictable events — referred to in the literature as 'super-emitters,' of which the Ohio incident was an extreme case — are responsible for a disproportionate share of total oil and gas methane emissions, " the EDF notes. But these emissions have generally not been included in EPA inventories.""
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2294 on: December 17, 2019, 10:02:44 PM »
...
One example of billions of that.... When the cod fisheries were collapsing on the great bank, then President Reagan responded by supporting the fishermen buying and building bigger and better boats with better equipment to catch more fish to maintain their lifestyle and their catch. That of course accelerated the destruction of the ecosystem and the evolutionary response to fish becomming smaller than the nets could catch, and smaller than were economically viable. This only stopped when there were simply no more fish to catch. At no point were those in charge or involved able or willing to recognize the right answer. They had to not just dramatically reduce the catch to allow the stocks to recover, they had to stop fishing for them entirely. Instead they chose precisely the opposite action and destroyed the ecosystem, and with it any potential of returning to "normal" in anyones lifetime.


Sam,

As an engineer I concur with your various assessments, and I note that not only does your example of conservative President Reagan counterproductive efforts to help cod fisherman work to accelerate the degradation of the environment, but the linked article discusses how left-wing efforts to implement green technology can also work to create a rebound effect that encourages the general public to consume more goods and thus to work to further degrade various Earth Systems:

Title: "Green technology will not save us"

https://ftalphaville.ft.com/2019/06/27/1561608044000/Green-technology-will-not-save-us/

Extract: "The UN also warns that using green technology may be less beneficial (and in some cases, more harmful) than expected. It’s called the rebound effect - instances where technologically-driven advances in energy efficiency increase, rather than decrease, consumption leading to net-zero (or worse) emissions. For example, because electric cars cost less to run, consumers may drive them further and more often which wipes out the eco-advantage these vehicles have over their gasoline-powered counterparts. According to the Breakthrough Institute, a research centre that promotes tech solutions for environmental and human challenges, this effect means that “for every two steps forward we take in energy savings through efficiency, rebound effects take us one (and sometimes more) steps backwards.” This may erode up to 50 per cent of the eco-benefits promised by green technology by 2030, according to a paper by Barker, Dagoumas and Rubin."

Best,
ASLR
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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2295 on: December 17, 2019, 10:14:37 PM »
...
The papers you have posted have been and continue to be an amazing summary of the state of our current knowledge of the physical world, of the path we are now on, and of the potentials for where that takes the Earth's systems, and with them - us.


The peer reviewed papers that I have hyperlinked to were made easier to find by reading the caveats cited by AR5 for all of their projections (note that consensus climate scientists are typically fully aware of the climate risks that they ignore, otherwise they would not state these caveats in the footnotes/appendices).  Once one knowns what to search for, almost any search engine can find the numerous subsequent papers written by other scientists whose job it is to investigate the numerous caveats cited in AR5-like consensus documents.
« Last Edit: December 17, 2019, 10:27:40 PM by AbruptSLR »
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AbruptSLR

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2296 on: December 17, 2019, 10:42:15 PM »
Per the linked article, Copernicus indicates that: "The twelve-month average temperature to November 2019 is 1.2°C above the level. The average for November 2019 alone is 1.3°C above the level."  Also, I note that currently GMSTA for the month of December is running warmer than November, so it is likely that GSMTA for 2019 may well be warmer than 1.2C above pre-industrial.

Title: "Surface air temperature for November 2019"

https://climate.copernicus.eu/surface-air-temperature-november-2019


I note that the European Copernicus projections indicate that GMSTA will almost certainly be above 1.2C, the first attached image/plot by Gavin Schmidt indicates that GISTEMP (baselined to pre-industrial) will likely be below 1.2C for 2019 (note that per GISTEMP 2016 was 1.23C above a pre-industrial baseline).  Assuming the Schmidt knows very well how to project GISTEMP values one month into the future, to me this highlights the variations in GMSTA measurements; which to my way of think represents yet another climate risk if one were to rely on only GISTEMP measurements.

Edit, the second attached image from the following linked website shows that the GMSTA for the month of December is currently running well above that for November 2019:
http://www.moyhu.org.s3.amazonaws.com/data/freq/ncep.html
« Last Edit: December 17, 2019, 10:50:18 PM by AbruptSLR »
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AbruptSLR

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2297 on: December 17, 2019, 11:55:45 PM »
The linked article discusses not only the risk of methane being released from subsea methane hydrates into the ocean, and eventually into the atmosphere, but also the risk that hydrate-capped reservoirs of liquid CO2 could also be abruptly released from the seafloor if/when the overlying hydrate cap is destabilized:

Title: "Huge amounts of greenhouse gases lurk in the oceans, and could make warming far worse"

https://www.nationalgeographic.com/science/2019/12/greenhouse-gases-lurk-in-oceans-could-make-warming-far-worse/

Extract: "Stores of methane and CO2 in the world's seas are in a strange, icy state, and the waters are warming, creating a ticking carbon time bomb."

“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

Sam

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2298 on: December 18, 2019, 12:02:17 AM »
...
One example of billions of that.... When the cod fisheries were collapsing on the great bank, then President Reagan responded by supporting the fishermen buying and building bigger and better boats with better equipment to catch more fish to maintain their lifestyle and their catch. That of course accelerated the destruction of the ecosystem and the evolutionary response to fish becomming smaller than the nets could catch, and smaller than were economically viable. This only stopped when there were simply no more fish to catch. At no point were those in charge or involved able or willing to recognize the right answer. They had to not just dramatically reduce the catch to allow the stocks to recover, they had to stop fishing for them entirely. Instead they chose precisely the opposite action and destroyed the ecosystem, and with it any potential of returning to "normal" in anyones lifetime.


Sam,

As an engineer I concur with your various assessments, and I note that not only does your example of conservative President Reagan counterproductive efforts to help cod fisherman work to accelerate the degradation of the environment, but the linked article discusses how left-wing efforts to implement green technology can also work to create a rebound effect that encourages the general public to consume more goods and thus to work to further degrade various Earth Systems:

Title: "Green technology will not save us"

https://ftalphaville.ft.com/2019/06/27/1561608044000/Green-technology-will-not-save-us/

Extract: "The UN also warns that using green technology may be less beneficial (and in some cases, more harmful) than expected. It’s called the rebound effect - instances where technologically-driven advances in energy efficiency increase, rather than decrease, consumption leading to net-zero (or worse) emissions. For example, because electric cars cost less to run, consumers may drive them further and more often which wipes out the eco-advantage these vehicles have over their gasoline-powered counterparts. According to the Breakthrough Institute, a research centre that promotes tech solutions for environmental and human challenges, this effect means that “for every two steps forward we take in energy savings through efficiency, rebound effects take us one (and sometimes more) steps backwards.” This may erode up to 50 per cent of the eco-benefits promised by green technology by 2030, according to a paper by Barker, Dagoumas and Rubin."

Best,
ASLR

ASLR,

I can go you one better - closer - in terms of impacts on climate change. The Powers that be (TPTB) decided that electricity use for lighting was low hanging fruit that they could attack to reduce energy consumption in the battle against climate change. New lighting was developed with a discovery in Japan that allowed for the energetically efficient production of blue light using photodiodes. This discovery was combined with phosphors (mostly pure orange) place on top of the diodes to absorb some of the blue and remit it as orange to produce a light that appears to humans to be sort of white. Depending on the mix of blue and orange the light is either harshly blue, or orangish (warm).

The technology advanced and the devices went into mass production. Governments around the world then mandated that these highly energy efficient lights be used and that "wasteful" incandescent lights be banned. The US passed this in the 2007 Energy and Infrastructure act.

Unfortunately no one seems to have thought this through. The safety standards for the lights are based off of retinal heating lessons involving lasers and bright light sources, with some minor recognition of the blue light hazard. In the case of LED lights they chose to set a "safe" standard of 1,000,000 watt-seconds/square meter/steradian. They then set a series of groups RG0, RG1, RG2 that allowed different illuminance values (100 watts/square meter/steradian for RG0) and allowed exposure times per day (10,000 seconds for RG0). The thinking was I suspect that 10,000 is a big number and 100 is sufficiently bright, that that seems a good combination to define as "exempt".

10,000 seconds is 2 hours and 47 minutes. After that period of exposure, no additional exposure is safe for the rest of the day.The body needs time to recover from the photobleaching of the retina.  Almost all of the lights being sold commercially are of this type. One manufacturer, SORAA, has lights that are somewhat different. They are based on producing violet light and using a broader range of colored phosphors.

A number of factors were not considered.

1) How people actually use light. (more than 10,000 seconds a day, and computer and device use adds to the exposure).
2) That once this level of exposure is exceeded that retinal injury IS occurring - and that that leads to insidious progressive blindness as the blue light bleaches the retina and triggers the body to order cells showing excessive damage to commit suicide.
3) That blue light also impacts the intrinsic photosensitive retinal ganglion cells (ipRGC) which control the circadian rhythm response
4) That the conversion of AC power to DC with inexpensive circuitry results in light that oscillates at twice the power frequency (100 or 120 hz in most of the world), AND shifts back and forth from intensely blue to intensely orange as the diodes drive the phosphors out of phase with themselves. This results in all manner of eye stress, guaranteed inability to focus as the eye tries to focus at two different focal lengths, and loud tinnitus, optical migraines and migraines as the brain sees motion everywhere in the visual field and activates the default mode network warning of danger.
5) That the LED lights do not have the throw of the lights they replaced, necessitating twice as many street lights
6) That the disruption of the circadian rhythm would inevitably lead to increase rates of hormone sensitive cancers, heart disease, obesity, type 2 diabetes, depression, suicide, behavior disorders, performance disorders, etc...
7) That advertisers would quickly realize that they could use this technology to light entire sides of buildings in full color displays, thereby increasing light pollution, circadian rhythm disruption and light pollution.
8 ) That the increase in blue light would destroy the night sky and astronomy
9) That animals, plants and insects would respond adversely to such light at night (e.g. salmon will not migrate upstream at night under bridges using LED light; that bird migration is disrupted, that insects are highly disrupted)
10) That people vary in the way they see and respond to light, with some being highly sensitive, and some much less so, that they have strong differences in color and light level response, that these change with age (young and old are especially vulnerable), or that some people are distinctly different in having eye diseases (AMD) or immune system disorders that are strongly impacted by intense blue light
11) That green light (which these lights generally do not produce) is incredibly important in reducing pain, and thereby offsetting opiate needs
12) That red light is essential in driving mitochondrial function through skin and tissue exposure to red light
10) and on and on and on

Lets look at just two of these aspects.

1) The sleep disrupting effects of blue light impacting the ipRGCs is well documented. The most recent study from Barcelona, Spain last year documented an actual observed 47% increase in the rate of breast cancers and a 105% increase in the rate of prostate cancers from the introduction of LED streetlights alone. Indoor use in the home of LED lighting further increased these rates by 50%.

Applied to the United States for example the first 15 years use of LED lighting (the expected life of the lights), should result in an increase of 20 million cancers and 4-5 million cancer fatalities. At some point attorneys will likely realize that their clients and their families can and should assert that the light injured them through the sleep impacts. Because the increase is so large (105% for prostate cancers), that it is more likely than not that the cancers were -caused- by the lights, making the lighting manufacturers potentially liable for ALL prostate cancers. I am not a lawyer, and this is for the courts to decide. But that seems all too obvious and preventable. For people with macular degeneration, no exposure is acceptable. They are effectively denied their rights to free travel and free association. They are injured everywhere these lights are used.

2) The flicker of the lights is causing differential impact to a small fraction of the population. For them the impact is extreme. They can no longer safely leave their homes at night, shop in stores, or participate in public functions or government. And they cannot safely work. The tinnitus, migraines and optical migraines essentially end their productive lives.

What should be clear is that the solution is to eliminate blue from all light use at night. because of the impact to sensitive people (infants, the elderly, those with AMD ...) that likely means essentially eliminating blue light from all lighting.

Interestingly, the increase in prostate and breast cancers occurred after fluorescent lighting entered the scene. It is conceptually possible that a large fraction of the base rate of these cancers may have been caused by the blue light from fluorescent lamps. This is unproven. But the direct impact of the LED lights on observed cancer rates, and the mechanistic understanding of how that works via the circadian rhythm impacts make that suggestive.

What is needed then to resolve this is the elimination of blue light from LED lighting, and the elimination of flicker. More over, to be effective the base of LED lighting already produced would need to be recalled and destroyed.

ALL of the energy used in the manufacture, distribution, recall, and destruction of these lights is then a sunk energy cost that cannot be recovered by using the lights through to the end of their lives.

Rather than saving energy, the conversion to LED lighting will have cost energy and worked against us in the battle to fight climate change.

Additionally, the Jevon's Paradox is fully on display. The intended reduction in energy use hasn't materialized because of the increased use of the lights compared to their predecessors and because of their use for new purposes.

But the simple idea that these lights are more efficient, therefor better, combined with the incredible complexity involved in understanding how light affects us, makes this a nearly impossible discussion.

Sam
« Last Edit: December 18, 2019, 08:04:25 AM by Sam »

vox_mundi

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Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Reply #2299 on: December 18, 2019, 01:30:34 AM »
Unusual Glacier Flow, First-Ever Look at Ice Stream Formation
https://phys.org/news/2019-12-ice-river-arctic-glacier-seas.html

Scientists have captured the birth of a high-speed ice feature for the first time on top of a Russian glacier.



In a remote archipelago of the Russian Arctic, Vavilov Ice Cap had been moving at a glacial pace for decades. Then, in 2013, it suddenly started spewing ice into the sea, flowing in what scientists call a glacial surge. But a new study suggests this surge has now become something entirely different.

The authors of the new study published in the AGU journal Geophysical Research Letters have documented what they believe is the first observation of a transition from a glacial surge to a longer-lasting flow called an ice stream.

Ice streams and glacial surges were believed to be separate phenomena driven by different mechanisms.

Quote
... if the authors of the new study are correct, glacial surges could instead be an early stage of an ice stream. If surging ice can form an ice stream on a glacier like Vavilov, then other ice caps (... Greenland, Antarctica) might also experience similar rapid ice loss

... "If that's true, we probably have to revise our predictions for the impact of global sea level rise in the future,"


- Whyjay Zheng, Ph.D. - lead author of the new study.

Glacial surges transport massive amounts of ice in a short amount of time, typically a few months to several years. On the other hand, ice streams can maintain a constant, rapid flow for decades to centuries.

From the time the surge at Vavilov began in 2013 until the spring of 2019, the ice cap lost 9.5 billion tons of ice, or 11 percent of the ice mass of the entire glacier basin. ...

Open Access: Whyjay Zheng et al, The Possible Transition From Glacial Surge to Ice Stream on Vavilov Ice Cap, Geophysical Research Letters (2019)
« Last Edit: December 18, 2019, 01:38:01 AM by vox_mundi »
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