Sea Level Rise and Social Cost of Carbon

[Lennart van der Linde]

National Geographic article on Hansen et al:
http://news.nationalgeographic.com/2015/07/150721-james-hansen-sea-level-rise-climate-change-global-warming-science/?utm_source=Twitter&utm_medium=Social&utm_content=link_tw20150722news-sealevel&utm_campaign=Content&sf11210763=1

[Lennart van der Linde]

The paper itself should appear here, one of these days:
http://www.atmos-chem-phys-discuss.net/papers_in_open_discussion.html

[AbruptSLR]

The following extract about Hansen et al (2015) new paper indicates that: (a) sea level could rise by 4.9m (16-ft) by 2100; and (b) this paper is primarily an elaboration on projections that Hansen and his various co-authors have been making for at least 20-years.


http://news.discovery.com/earth/global-warming/dire-climate-warning-raises-questions-not-answers-150721.htm

Extract: "The paper uses paleoclimate data and modeling to show that if ice sheets in Greenland and West Antarctica continue to double their melt rates every 10 years as they currently are, sea levels could rise up to 16 feet as soon as 2100.
A sudden influx of fresh, cold water to oceans around Antarctica and Greenland could have other notable impacts. The study argues that it could slow down ocean conveyor belts that shuttle water around the world’s oceans and alter air temperatures and storm tracks. Most provocatively, the study indicates it could cause cooling over the southern third of the globe as well as parts of the northern Atlantic and Europe and slow warming in other parts of the globe."

[Shared Humanity]

It's game over if we get 5m SLR by 2100. The world economy will be delivered a gut punch which it cannot survive.

[Sleepy]

SH, I think 3m is enough to 2100 and it's also what I think is plausible. Let's see what happens with the measurements when the ongoing El Nino fades out. It will drop back initially but then I think we will see larger increases the following two years after.

[Sleepy]

And oh, it's nice to see you posting again ASLR!
Guess I'm not the only one waiting for the Hansen paper.

[AbruptSLR]

And oh, it's nice to see you posting again ASLR!
Guess I'm not the only one waiting for the Hansen paper.

Sleepy,

It is an honor to be posting again with such fine fellows.  Also, Lennart provided the following link to Hansen et al's paper in another thread:

Hansen, J., Sato, M., Hearty, P., Ruedy, R., Kelley, M., Masson-Delmotte, V., Russell, G., Tselioudis, G., Cao, J., Rignot, E., Velicogna, I., Kandiano, E., von Schuckmann, K., Kharecha, P., Legrande, A. N., Bauer, M., and Lo, K.-W.: Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modeling, and modern observations that 2 °C global warming is highly dangerous, Atmos. Chem. Phys. Discuss., 15, 20059-20179, doi:10.5194/acpd-15-20059-2015, 2015.

http://www.atmos-chem-phys-discuss.net/15/20059/2015/acpd-15-20059-2015.html

Abstract. There is evidence of ice melt, sea level rise to +5–9 m, and extreme storms in the prior interglacial period that was less than 1 °C warmer than today. Human-made climate forcing is stronger and more rapid than paleo forcings, but much can be learned by combining insights from paleoclimate, climate modeling, and on-going observations. We argue that ice sheets in contact with the ocean are vulnerable to non-linear disintegration in response to ocean warming, and we posit that ice sheet mass loss can be approximated by a doubling time up to sea level rise of at least several meters. Doubling times of 10, 20 or 40 years yield sea level rise of several meters in 50, 100 or 200 years. Paleoclimate data reveal that subsurface ocean warming causes ice shelf melt and ice sheet discharge. Our climate model exposes amplifying feedbacks in the Southern Ocean that slow Antarctic bottom water formation and increase ocean temperature near ice shelf grounding lines, while cooling the surface ocean and increasing sea ice cover and water column stability. Ocean surface cooling, in the North Atlantic as well as the Southern Ocean, increases tropospheric horizontal temperature gradients, eddy kinetic energy and baroclinicity, which drive more powerful storms. We focus attention on the Southern Ocean's role in affecting atmospheric CO2 amount, which in turn is a tight control knob on global climate. The millennial (500–2000 year) time scale of deep ocean ventilation affects the time scale for natural CO2 change, thus the time scale for paleo global climate, ice sheet and sea level changes. This millennial carbon cycle time scale should not be misinterpreted as the ice sheet time scale for response to a rapid human-made climate forcing. Recent ice sheet melt rates have a doubling time near the lower end of the 10–40 year range. We conclude that 2 °C global warming above the preindustrial level, which would spur more ice shelf melt, is highly dangerous. Earth's energy imbalance, which must be eliminated to stabilize climate, provides a crucial metric.


However, as the linked Mashable article on this subject, the science establishment is stating that the Hansen et al paper raises more questions than it provides answers:

http://mashable.com/2015/07/22/james-hansen-scary-new-climate-study/

[Sleepy]

Thanks ASLR!
I only checked my mail this morning and not the topics, I see now that he posted it one hour before my comment here this morning.
Time to read.

[Laurent]

There is no way we will limit temperature at 2°C we are on track for 4°C and more. The doubling every 10 years is now, but there is an acceleration in the acceleration, Does someone plot that ?

[AbruptSLR]

There is no way we will limit temperature at 2°C we are on track for 4°C and more. The doubling every 10 years is now, but there is an acceleration in the acceleration, Does someone plot that ?

Laurent,

The following is a re-post from January in this thread; however, to check to see ice sheet mass loss acceleration trends I recommend looking at the Antarctic thread, and/or to wait for the Alley et al paper on that topic later this fall.

Best,
ASLR

Re-post begins here:

The linked reference finds that the acceleration in sea level rise seen in recent decades is more rapid (by about 25% since 1990, see attached plot & caption) than scientists previously thought:

Hay CC, Morrow E, Kopp RE, Mitrovica JX, (2015) "Probabilistic reanalysis of twentieth-century sea-level rise", Nature. 2015 Jan 14. doi: 10.1038/nature14093

http://www.nature.com/nature/journal/vaop/ncurrent/full/nature14093.html

Abstract: "Estimating and accounting for twentieth-century global mean sea-level (GMSL) rise is critical to characterizing current and future human-induced sea-level change. Several previous analyses of tide gauge records—employing different methods to accommodate the spatial sparsity and temporal incompleteness of the data and to constrain the geometry of long-term sea-level change—have concluded that GMSL rose over the twentieth century at a mean rate of 1.6 to 1.9 millimetres per year. Efforts to account for this rate by summing estimates of individual contributions from glacier and ice-sheet mass loss, ocean thermal expansion, and changes in land water storage fall significantly short in the period before 1990. The failure to close the budget of GMSL during this period has led to suggestions that several contributions may have been systematically underestimated. However, the extent to which the limitations of tide gauge analyses have affected estimates of the GMSL rate of change is unclear. Here we revisit estimates of twentieth-century GMSL rise using probabilistic techniques and find a rate of GMSL rise from 1901 to 1990 of 1.2 ± 0.2 millimetres per year (90% confidence interval). Based on individual contributions tabulated in the Fifth Assessment Report of the Intergovernmental Panel on Climate Change, this estimate closes the twentieth-century sea-level budget. Our analysis, which combines tide gauge records with physics-based and model-derived geometries of the various contributing signals, also indicates that GMSL rose at a rate of 3.0 ± 0.7 millimetres per year between 1993 and 2010, consistent with prior estimates from tide gauge records. The increase in rate relative to the 1901–90 trend is accordingly larger than previously thought; this revision may affect some projections of future sea-level rise."


Caption: "Time series of global mean sea level for the period 1900-2010. Figure shows estimates of sea level from the two methods used in this study: 'KS' (blue line) and 'GPR' (black line), and two methods used in the latest IPCC report: 'Ref.4' (purple line) from Church et al. ( 2011) and 'Ref. 3' (red line) from Jevrejeva et al. ( 2008). Inset table shows trends for three different time periods. Source: Hay et al. (2015)"

See also:
http://www.carbonbrief.org/blog/2015/01/global-sea-levels-rising-faster-than-previously-thought-study-shows/
http://in.reuters.com/article/2015/01/14/climatechange-seas-idINL6N0US3IZ20150114

[Anne]

English language interview with Stefan Rahmstorf by Irene Quaile of Deutsche Welle, broadcast on 16 July. No real news except his optimism about the possibility of reducing FF use and keeping below 2^oC increase in the light of progress in development of renewables. He has hopes of the UN Paris summit and says he sees an increase in political will but doesn't explain why he sees this... He goes on to outline the horrors of SLR.
(Just under 8 minutes)
http://www.dw.com/en/living-planet-living-planet-in-harmony-with-nature-2015-07-17/e-18531083#18589842

[Laurent]

Thanks AbruptSLR !

[AbruptSLR]

Thanks AbruptSLR !

Since I raised the topic of accelerating ice mass loss from the WAIS, I thought that I would provide the following linked reference and associated image, in order to help quantify the current rate of acceleration, i.e. "Ignoring GIA model uncertainty, over the period 2003–2014, West Antarctica has been losing ice mass at a rate of −121 ±8 Gt/yr and has experienced large acceleration of ice mass losses along the Amundsen Sea coast of −18 ±5 Gt/yr2, doubling the mass loss rate in the past six years":

Christopher Harig & Frederik J. Simons (2015), "Accelerated West Antarctic ice mass loss continues to outpace East Antarctic gains", Earth Planet. Sc. Lett., 415, 134-141, doi:10.1016/j.epsl.2015.01.029
 

http://www.princeton.edu/geosciences/people/simons/pdf/EPSL-2015a.pdf


Abstract: "While multiple data sources have confirmed that Antarctica is losing ice at an accelerating rate, different measurement techniques estimate the details of its geographically highly variable mass balance with different levels of accuracy, spatio-temporal resolution, and coverage. Some scope remains for methodological improvements using a single data type. In this study we report our progress in increasing the accuracy and spatial resolution of time-variable gravimetry from the Gravity Recovery and Climate Experiment (GRACE). We determine the geographic pattern of ice mass change in Antarctica between January 2003 and June 2014, accounting for glacio-isostatic adjustment (GIA) using the IJ05_R2 model.  Expressing the unknown signal in a sparse Slepian basis constructed by optimization to prevent leakage out of the regions of interest, we use robust signal processing and statistical estimation methods.  Applying those to the latest time series of monthly GRACE solutions we map Antarctica’s mass loss in space and time as well as can be recovered from satellite gravity alone. Ignoring GIA model uncertainty, over the period 2003–2014, West Antarctica has been losing ice mass at a rate of −121 ±8 Gt/yr and has experienced large acceleration of ice mass losses along the Amundsen Sea coast of −18 ±5 Gt/yr2, doubling the mass loss rate in the past six years. The Antarctic Peninsula shows slightly accelerating ice mass loss, with larger accelerated losses in the southern half of the Peninsula. Ice mass gains due to snowfall in Dronning Maud Land have continued to add about half the amount of West Antarctica’s loss back onto the continent over the last decade. We estimate the overall mass losses from Antarctica since January 2003 at −92 ±10 Gt/yr."


See also
http://www.princeton.edu/main/news/archive/S43/04/11E77/index.xml?section=topstories

Caption: "Princeton University researchers "weighed" Antarctica's ice sheet using gravitational satellite data and found that during the past decade, Antarctica's massive ice sheet lost twice the amount of ice in its western portion compared to what it accumulated in the east. The researchers used monthly data from GRACE, or the Gravity Recovery and Climate Experiment, a dual-satellite mission that measures gravity changes; as Antarctic land ice melts, the reduction in ice mass is picked up by GRACE. In the past 11 years, the Antarctic ice sheet lost 92 billion tons of ice per year, which, if stacked on the island of Manhattan, would be more than a mile high — more than five times the height of the Empire State Building. As shown in the figure above, from Jan. 2003 to June 2014, the vast majority of ice loss was from West Antarctica's Amundsen Sea region (box a) and the Antarctic Peninsula (box b) that winds up toward South America. The ice sheet on East Antarctica (box c) primarily thickened during that same time. The color scale indicates mass — equivalent to centimeters of water — of the land ice, with red denoting the largest loss and blue standing for the largest gain. (Image by Christopher Harig)

[AbruptSLR]

The University of Colorado has updated both their change in global mean sea level trend line and their correlation of the detrended GMSL time series vs the MEI time series (see attached plots, respectively) through July 23 2015.  As it seems likely to me that we are very likely headed towards a super El Nino event in 2015-2016 comparable to the 97-98 event; it seems to me that not only is the El Nino leading to record high sea levels but also that SLR contributions from the ice sheets are accelerating:

http://sealevel.colorado.edu/

[Lennart van der Linde]

Yi et al 2015 find a recent acceleration in SLR (as posted earlier, but good to keep in mind here):
http://onlinelibrary.wiley.com/wol1/doi/10.1002/2015GL063902/abstract

Abstract
"The global mean sea level (GMSL) was reported to have dropped 5 mm due to the 2010/2011 La Niña and have recovered in 1 year. With longer observations, it is shown that the GMSL went further up to a total amount of 11.6 mm by the end of 2012, excluding the 3.0 mm/yr background trend. A reconciled sea level budget, based on observations by Argo project, altimeter, and gravity satellites, reveals that the true GMSL rise has been masked by El Niño–Southern Oscillation-related fluctuations and its rate has increased since 2010. After extracting the influence of land water storage, it is shown that the GMSL has been rising at a rate of 4.4 ± 0.5 mm/yr for more than 3 years, due to an increase in the rate of both land ice loss and steric change."

[Sigmetnow]

"Compound flooding."  The risks are increasing.

Scientists Identify 'Triple Threat' Endangering US Coastal Cities

A trio of phenomena attributed at least in part to climate change—sea-level rise, storm surges, and heavy rainfall—poses an increasing risk to residents of major U.S. cities including Boston, New York, Houston, San Diego, and San Francisco, according to new research published Monday in the journal Nature Climate Change.

http://www.commondreams.org/news/2015/07/27/scientists-identify-triple-threat-endangering-us-coastal-cities

[Sigmetnow]

Florida leads nation in property at risk from climate change

Florida has more private property at risk from flooding linked to climate change than any other state, an amount that could double in the next four decades, according to a new report by the Risky Business Project.

By 2030, $69 billion in coastal property in Florida could flood at high tide that is not at risk today, the report found. That amount is projected to climb to $152 billion by 2050.

http://www.miamiherald.com/news/local/environment/article29029159.html

[Shared Humanity]

Florida leads nation in property at risk from climate change

Florida has more private property at risk from flooding linked to climate change than any other state, an amount that could double in the next four decades, according to a new report by the Risky Business Project.

By 2030, $69 billion in coastal property in Florida could flood at high tide that is not at risk today, the report found. That amount is projected to climb to $152 billion by 2050.

http://www.miamiherald.com/news/local/environment/article29029159.html

If you want to retire to Miami, go for it. Just make sure you rent and don't buy. In fact, I would hesitate to buy any property in low lying coastal regions of the U.S. Except in North Carolina, of course, where the legislature passed laws prohibiting sea level rise....or something like that.

[AbruptSLR]

The linked August 26 2015 announcement indicates that several feet of SLR is unavoidable in the future:

http://www.jpl.nasa.gov/news/news.php?feature=4700

[Sigmetnow]

After Hurricane Katrina, New Orleans' Climate Conundrum: Fight or Flight?
A decade later, many still wrestle with staying home vs. leaving—a decision millions more will face along the coasts as seas rise and storms intensify.
http://insideclimatenews.org/news/27082015/after-katrina-new-orleans-climate-conundrum-fight-or-flight

[Sigmetnow]

WaPo on NASA's "Oceans Melting Greenland" study.

The troubling reasons why NASA is so focused on studying sea level rise
http://www.washingtonpost.com/news/energy-environment/wp/2015/08/26/the-troubling-reasons-why-nasa-is-so-focused-on-studying-on-sea-level-rise/

[Lennart van der Linde]

SLR over the past 20 yrs was 7.4cm, so on average 3.7mm/yr:
http://www.carbonbrief.org/blog/2015/08/new-nasa-videos-show-stark-ice-loss-from-earths-ice-sheets/?utm_content=buffer0f12f&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer

Acceleration?

[Sigmetnow]

@Climatologist49: Coastal #flooding happening in #Barrow, AK, right now. Image source: http://t.co/gN4AZL2Eml http://t.co/1sOsFe5jln

https://twitter.com/climatologist49/status/636960959265828864

Barrow Sea Ice Webcam
http://seaice.alaska.edu/gi/observatories/barrow_webcam

[Sigmetnow]

Barrow, AK.  Waves crashing over sea wall.

[Sigmetnow]

Gale.

[AbruptSLR]

SLR over the past 20 yrs was 7.4cm, so on average 3.7mm/yr:
http://www.carbonbrief.org/blog/2015/08/new-nasa-videos-show-stark-ice-loss-from-earths-ice-sheets/?utm_content=buffer0f12f&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer

Acceleration?

As the two IPCC figures point-out, until now the acceleration of ice mass loss from ice sheets has been masked by the deceleration of ice mass loss from glaciers.  However, now the ice sheets are beginning to dominate the SLR trend so we can expect an upward bending curve instead of a straight line:

Caption for Figure 1: Recent trends in glacier mass loss during (a) 1850-2010 and (b) 1961-2010. Coloured lines indicate different models, shaded areas show uncertainty. Blue bars display number of measured mass balance glaciers (IPCC, 2013).

Caption for Figure 2: Contribution of global glaciers (red), Greendland (green) and Antarctica (blue) to sea level rise between 1992-2012. Positive correlation between cumulative ice mass loss and sea level equivalent, shaded areas indicate uncertainty.

[AbruptSLR]

Also, note that in the attached NASA (Gollard 2015) image GRACE shows that the combined ice mass loss has contributed 1.9 mm/year to SLR; and as ice mass loss from ice sheets accelerate you can expect this number to increase:

[Sigmetnow]

Barrow: Attempting to reinforce the sea wall.

[Sigmetnow]

Examining Bjørn Lomborg's (denier) position on sea level rise.  By Stefan Rahmstorf.

...Lomborg has a simple, single message: don’t worry about reducing fossil emissions. Whether he denies or plays down the seriousness of global warming, sings the praises of adaptation, advocates to prioritize other problems or pushes geoengineering, the message is always the same: anything is better than phasing out fossil fuels.

http://www.realclimate.org/index.php/archives/2015/08/bjorn-lomborg-just-a-scientist-with-a-different-opinion/#.dpuf

[skanky]

This article on NASA's issues from SLR gives an indicator to future problems. Magnify these issues across the country, with multiple civilian ownership and critical infrastructure, etc. and contrast that to a single, scientific and engineering agency planning, then also consider the same issues across many different countries.

http://earthobservatory.nasa.gov/Features/NASASeaLevel/?src=features-hp&eocn=home&eoci=feature

[Steven]

New paper on sea level during the mid-Pliocene warm period:

http://geology.gsapubs.org/content/early/2015/08/21/G36999.1.abstract

From the abstract:

The mid-Pliocene warm period (MPWP, 3.3-2.9 Ma), with reconstructed atmospheric pCO2 of 350-450 ppm, represents a potential analogue for climate change in the near future. Current highly cited estimates place MPWP maximum global mean sea level (GMSL) at 21 ± 10 m above modern, requiring total loss of the Greenland and marine West Antarctic Ice Sheets and a substantial loss of the East Antarctic Ice Sheet, with only a concurrent 2–3 °C rise in global temperature.

...

we present a new Pliocene GMSL estimate of 9-13.5 m above modern, which suggests that the East Antarctic Ice Sheet is less sensitive to radiative forcing than previously inferred from the geologic record.

[AbruptSLR]

As alarming as the linked NASA video is about sea level rise over the past 23-years of the satellite era, it is important to remember that this period is dominated by the hiatus, so get reading to see still faster rates of SLR now that we are in a positive PDO period:

http://www.techinsider.io/nasa-animated-sea-level-rise-map-climate-change-2015-9

[Sigmetnow]

Mashable:
"Those results may be too conservative"

Burn all fossil fuels, lose all of Florida, study says

Burning all of the currently accessible oil, natural gas and coal in the world would have catastrophic consequences for coastal populations around the world, a new study shows.

The amount of planet-warming greenhouse gases released by this combustion would be sufficient to warm the planet by at least 16 degrees Fahrenheit on average and melt the entire Antarctic ice sheet — as well as Greenland.

In other words, we could be headed for a completely ice-free world.
...
The study, published on Friday in the journal Science Advances, is the first to look at the long-term consequences of burning all of the fossil fuels currently in the ground (and considered to be economically accessible) when it comes to temperature trends and sea level rise. It adds to the growing body of evidence showing that in order to avert the worst impacts of global warming, a significant amount of available fossil fuels will have to stay in the ground.

http://mashable.com/2015/09/11/antarctica-complete-melt-fossil-fuels/

[Sigmetnow]

This sign from the People's Climate March, in New York City, September 2014.

[Sigmetnow]

Pacific leaders respond to Australian minister's sea level remarks

Pacific leaders have hit out at the insensitivity of an Australian minister’s apparent joke at the expense of low-lying nations struggling against rising sea levels.

http://www.theguardian.com/australia-news/2015/sep/11/pacific-leaders-australian-minister-sea-levels-tony-de-brum-marshall-islands

[Sigmetnow]

Not surprising, given the previous comment above.

Tony Abbott faces down Pacific island nations' calls for tougher action on climate change
http://www.abc.net.au/news/2015-09-11/pacific-leaders-fail-to-reach-consensus-on-climate-change/6767038

[AbruptSLR]

The following is AVISO SLR data from the begin of 2015 until late June 2015, showing the highest SLR satellite measurement ever reported through that date:

2015.001879 7.390021e-02
2015.029027 7.370672e-02
2015.056175 7.418527e-02
2015.083322 7.546662e-02
2015.110470 7.684320e-02
2015.137617 7.744393e-02
2015.164765 7.704646e-02
2015.191912 7.625656e-02
2015.219060 7.592576e-02
2015.246207 7.635819e-02
2015.273355 7.704768e-02
2015.300503 7.722826e-02
2015.327650 7.661682e-02
2015.354798 7.578150e-02
2015.381945 7.570608e-02
2015.409093 7.665680e-02
2015.436240 7.803072e-02
2015.463388 7.922665e-02
2015.490535 8.002329e-02

Edit: see the attached plot

[Sigmetnow]

Satire from The Onion.

Atlantic Ocean Excited To Move Into Beautiful Beachfront Mansion Soon
http://www.theonion.com/article/atlantic-ocean-excited-move-beautiful-beachfront-m-51303

[Sigmetnow]

This is awesome!    I imagine they could also warn about forecasted storm surge, if done before the storm.

Moo-ve to Higher Ground- The Tsunami Sirens of Cannon Beach Oregon
When staring at a grave threat, be funny about it.
https://medium.com/west-coast-life-frankystein123/moo-ve-to-higher-ground-the-tsunami-sirens-of-cannon-beach-oregon-d30f0e683f1

[Sigmetnow]

Pacific Islanders Plead for Urgent Climate Action as Seas Rise
http://www.bloomberg.com/news/articles/2015-09-21/pacific-islanders-plead-for-urgent-climate-action-as-seas-rise

[Sigmetnow]

Arctic melting will cost the global economy £33 trillion by end of next century, scientists calculate

The melting of the Arctic permafrost and the subsequent release of carbon dioxide and methane gas into the atmosphere will alone add an extra $43 trillion (£33tn) cost of climate change to the global economy by the end of the next century, scientists have calculated.

This represents a 13 per cent increase on the predicted economic impact of climate change by 2200, up from $326tn to $369tn, according to a study by Cambridge University and the US National Snow and Ice Data Centre in Boulder, Colorado.

http://www.independent.co.uk/environment/climate-change/arctic-melting-will-alone-cost-the-global-economy-33tn-by-end-of-next-century-scientists-calculate-10511426.html

[AbruptSLR]

The linked reference indicates that the is still missing information necessary to close the Sea Level Budget:

Dieng, H. B., Cazenave, A., von Schuckmann, K., Ablain, M., and Meyssignac, B.: Sea level budget over 2005–2013: missing contributions and data errors, Ocean Sci., 11, 789-802, doi:10.5194/os-11-789-2015, 2015.

http://www.ocean-sci.net/11/789/2015/os-11-789-2015.pdf

Abstract: "Based on the sea level budget closure approach, this study investigates the residuals between observed global mean sea level (GMSL) and the sum of components (steric sea level and ocean mass) for the period January 2005 to December 2013. The objective is to identify the impact of errors in one or several components of the sea level budget on the residual time series. This is a key issue if we want to constrain missing contributions such as the contribution to sea level rise from the deep ocean (depths not covered by observations). For that purpose, we use several data sets as processed by different groups: six altimetry products for the GMSL, four Argo products plus the ORAS4 ocean reanalysis for the steric sea level and three GRACE-based ocean mass products. We find that over the study time span, the observed differences in trend of the residuals of the sea level budget equation can be as large as ~ 0.55 mm yr−1 (i.e., ~ 17 % of the observed GMSL rate of rise). These trend differences essentially result from differences in trends of the GMSL time series. Using the ORAS4 reanalysis (providing complete geographical coverage of the steric sea level component), we also show that lack of Argo data in the Indonesian region leads to an overestimate of the absolute value of the residual trend by about 0.25 mm yr−1. Accounting for this regional contribution leads to closure of the sea level budget, at least for some GMSL products. At short timescales (from sub-seasonal to interannual), residual anomalies are significantly correlated with ocean mass and steric sea level anomalies (depending on the time span), suggesting that the residual anomalies are related to errors in both GRACE-based ocean mass and Argo-based steric data. Efforts are needed to reduce these various sources of errors before using the sea level budget approach to estimate missing contributions such as the deep ocean heat content."

[Sigmetnow]

More Than 400 U.S. Cities May Be 'Past The Point Of No Return' With Sea Level Threats
But there are still cities that could be saved by reducing carbon emissions.
http://www.huffingtonpost.com/entry/us-cities-sea-level-threats_561d338fe4b0c5a1ce60a45c


Climate Central's interactive U.S. map lets you choose between different emissions and duration scenarios to see the eventual Sea Level Rise.
http://choices.climatecentral.org/#10/25.7708/-80.2544?compare=scenarios&carbon-end-yr=2050&scenario-a=unchecked&scenario-b=extreme-cuts

[AbruptSLR]

The University of Colorado posted the attached sea level trend line plot yesterday, Oct 16 2015, indicating that currently sea level is increase significantly faster than during the 1997 Super El Nino event, indicating that at a minimum the variance for SLR is increasing and more likely that ice mass contribution to SLR is accelerating:

[AbruptSLR]

The linked open access reference concludes that the oceanic part of the Earth is expanding and is thus contributing directly to SLR; which is a surprise to me as I believe that current estimates of GIA assume that the oceanic part of the Earth is contracting as the land part of the Earth rebounds from the last ice age:

Wenbin Shen, Ziyu Shen, Rong Sun and Yuri Barkin (July 2015), "Evidences of the expanding Earth from space-geodetic data over solid land and sea level rise in recent two decades", Geodesy and Geodynamics, Volume 6, Issue 4, Pages 248–252, doi:10.1016/j.geog.2015.05.006


http://www.sciencedirect.com/science/article/pii/S1674984715000518

Abstract: "According to the space-geodetic data recorded at globally distributed stations over solid land spanning a period of more than 20-years under the International Terrestrial Reference Frame 2008, our previous estimate of the average-weighted vertical variation of the Earth's solid surface suggests that the Earth's solid part is expanding at a rate of 0.24 ± 0.05 mm/a in recent two decades. In another aspect, the satellite altimetry observations spanning recent two decades demonstrate the sea level rise (SLR) rate 3.2 ± 0.4 mm/a, of which 1.8 ± 0.5 mm/a is contributed by the ice melting over land. This study shows that the oceanic thermal expansion is 1.0 ± 0.1 mm/a due to the temperature increase in recent half century, which coincides with the estimate provided by previous authors. The SLR observation by altimetry is not balanced by the ice melting and thermal expansion, which is an open problem before this study. However, in this study we infer that the oceanic part of the Earth is expanding at a rate about 0.4 mm/a. Combining the expansion rates of land part and oceanic part, we conclude that the Earth is expanding at a rate of 0.35 ± 0.47 mm/a in recent two decades. If the Earth expands at this rate, then the altimetry-observed SLR can be well explained."

[jai mitchell]

if you expand the edges of a bowl, it pushes the water higher (less volume inside)

[AbruptSLR]

if you expand the edges of a bowl, it pushes the water higher (less volume inside)

This image from the linked open access paper indicates that the issue is somewhat complex.

[Sigmetnow]

Miami-Dade Clerk Of Courts Calls For Sea-Level Rise Superfund
http://wlrn.org/post/miami-dade-clerk-courts-calls-sea-level-rise-superfund

[Laurent]

Perth's double whammy: as sea levels rise the city itself is sinking
http://www.theguardian.com/environment/2015/oct/22/perths-double-whammy-as-sea-levels-rise-the-city-itself-is-sinking

Growing demand for water in Perth has caused the city to sink at up to 6mm a year and could be responsible for an apparent acceleration in the rate of sea level rise, according to new research released by Curtin University.

[Shared Humanity]

Miami-Dade Clerk Of Courts Calls For Sea-Level Rise Superfund
http://wlrn.org/post/miami-dade-clerk-courts-calls-sea-level-rise-superfund

On this thread, I have argued repeatedly that we are seriously underestimating the devastation that sea level rise will have on the global economy. I have argued that the wholesale destruction of property will actually result in the total collapse of the worldwide financial system that serves as the foundation of global capitalism. I will attempt to explain my point of view one more time and will use this linked article to make my point.

In the linked article the "Miami-Dade Clerk of Courts, Harvey Ruvin, sent a letter last week to South Florida members of Congress urging for the creation of a Federal Resiliency Superfund." He said that changes "in ocean levels threaten $6 trillion worth state property as well as the lives of the millions of South Floridians."

If you look at the picture at the top of the article, it conjures up a vision of Venice, buildings surrounded by water. This picture is not far from the truth as sea level rise will not result in the complete destruction of built structures. These magnificent structures will remain as monuments to our stupidity. Sewers are underground and it is estimated that a 1 meter rise in sea level over the current levels will render useless the waste water removal and treatment infrastructure in Dade County. The county will frequently and repeatedly be standing in a pool of raw sewage, rendering the county unfit for human habitation. Fresh water distribution is at risk as well but since water distribution is under pressure, it can withstand saltwater intrusion better than waste water infrastructure.

So why will this destruction of the built up wealth of $6 trillion damage the system of capitalism? It is not the structures themselves but the links these structures have with the financial system that will cause the damage. Mortgages and other debt issued against the value of this property will go into default. This debt has been packaged and sold into the financial markets and form the basis for pensions and wealth that is spread across the planet. The financial wealth that is supported by this debt is then borrowed against as well. The insurance and reinsurance industries are at risk as obligations against the physical structures and financial instruments will play havoc.

If you were paying attention in 2007, this is the process that nearly brought down the worldwide financial system. Only a coordinated effort by the banks of the entire developed world prevented this collapse as western nations flooded the system with an unprecedented amount of liquidity. This liquidity continues to prop up a still fragile financial system and the historically low interest rates are all the evidence that you need to realize that this excessive liquidity is still in the system.

So is a $6 trillion destruction of wealth really that large? Can that trigger the same kind of reaction in the financial markets that the destruction of wealth caused by the collapse of the housing bubble in 2007?

When the housing market bubble collapsed.....

http://fivethirtyeight.com/features/why-the-housing-bubble-tanked-the-economy-and-the-tech-bubble-didnt/

"from 2007 to 2009, the value of real estate owned by U.S. households fell by nearly the same amount — $6 trillion"

Please keep in mind, that $6 trillion of real estate threatened by sea level rise is only in Florida. How many other coastal communities are at risk in the U.S.? How many globally?

The global financial system will not be able to withstand the devastation wrought by global warming and sea level rise is only one feature of global warming that will destroy the accumulated wealth in the system.