Sea Level Rise and Social Cost of Carbon

[Lennart van der Linde]

De Winter et al 2017, Impact of asymmetric uncertainties in ice sheet dynamics on regional sea level projections:
https://www.nat-hazards-earth-syst-sci.net/17/2125/2017/

"Abstract
Currently a paradigm shift is made from global averaged to spatially variable sea level change (SLC) projections. Traditionally, the contribution from ice sheet mass loss to SLC is considered to be symmetrically distributed. However, several assessments suggest that the probability distribution of dynamical ice sheet mass loss is asymmetrically distributed towards higher SLC values. Here we show how asymmetric probability distributions of dynamical ice sheet mass loss impact the high-end uncertainties of regional SLC projections across the globe. For this purpose we use distributions of dynamical ice sheet mass loss presented by Church et al. (2013), De Vries and Van de Wal (2015) and Ritz et al. (2015). The global average median can be 0.18 m higher compared to symmetric distributions based on IPCC-AR5, but the change in the global average 95th percentile SLC is considerably larger with a shift of 0.32 m. Locally the 90th, 95th and 97.5th SLC percentiles exceed +1.4, +1.6 and +1.8 m. The high-end percentiles of SLC projections are highly sensitive to the precise shape of the probability distributions of dynamical ice sheet mass loss. The shift towards higher values is of importance for coastal safety strategies as they are based on the high-end percentiles of projections."

[sidd]

Sea level rise coming home, the market is paying attention (Halleluia! who woulda thunk it. The real estate market, epecially on the coasts is a wretched hive of villainy))

The first sentence of the abstract is "Homes exposed to sea level rise (SLR) sell at a 7% discount relative to observably equivalent unexposed properties equidistant from the beach."

More:

"This effect is primarily driven by properties unlikely to be inundated for over half a century, suggesting that it is driven by investors pricing long horizon concerns about SLR costs."

" ... the SLR exposure discount has increased substantially over the past decade, coinciding with both increased awareness and more pessimistic prognoses about the extent and speed of rising oceans. In particular, we document increased transaction volume and lower prices for sophisticated buyers following the significant revisions of the IPCC’s 2013 release, which increased SLR projects and awareness."

" ... properties that will experience ocean encroachment after 1 foot of global average sea level rise trading at a 22%, 2-3 feet at a 17% discount, 4-5 feet at a 9% discount and 6 feet at a 6% discount. [4] Using the long run discount rate provided by Giglio et al. (2014) and assuming complete loss at the onset of inundation, we estimate that markets expect 1 foot of sea level rise within 35 years, 2-3 feet within 45 years, 4-5 feet after 65 years, and 6 feet in 80 years. These results are consistent with the medium to high projections provided in Parris et al. (2012) and utilized by the NOAA in their 2012 report.

" ... exposed non-owner occupied properties trade at a 10% to 11% discount, relative to comparable non-exposed properties. "

" ... expectations regarding future SLR have steadily increased over the course of our sample period ... At the beginning of our sample in 2007 we find no significant difference between the prices of exposed and unexposed properties. By the end of our sample in 2016, exposed non-owner occupied properties are priced approximately 13.5% below comparable unexposed properties."

" ... we find evidence that the discount applied to non-owner occupied properties increased from 8.1% to 14.0% following the IPCC release.

" ... consistent with the idea that as information about SLR risks comes to light, exposed properties should be more likely to transact, we find that the annual probability of turnover is approximately 0.2 percentage points higher for exposed properties between 2011 and 2016 (relative to a base transaction rate of approximately 11% for all properties). This is entirely driven by the period following the IPCC report where we see a 0.8 percentage point increase in the annual probability of an exposed property transacting."

I see a remake of the "The Big Short" coming up. A good title might be "Underwater."

Open access (no doi ?!) . Read the whole thing:

"Disaster on the Horizon: The Price Effect of Sea Level Rise," Asaf Bernstein, Matthew Gustafson, and Ryan Lewis

https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3073842

sidd

[Shared Humanity]

This is great news. If pricing adjusts properly due to the availability of accurate information, the slide in coastal property values will serve to soften the damage to our financial system. Death by a thousand cuts is far better than cutting off a limb.

[sidd]

Note that the Bernstein paper remarks that the SLR discount is more pronounced in real estate held as an investment compared to owner occupied properties. Presumably if you live by the coast you don't want to imagine being flooded out or your home losing value, while if the property is a second home or a rental or held as investment you tend to be more clear eyed about valuations.


sidd

[Lennart van der Linde]

Kopp et al 2017 (with DeConto, Bader, Carling, Horton, Kulp, Oppenheimer, Pollard, Strauss), Evolving Understanding of Antarctic Ice-Sheet Physics and Ambiguity in Probabilistic Sea-Level Projections (final version of earlier published draft):
http://onlinelibrary.wiley.com/doi/10.1002/2017EF000663/epdf

"Abstract
Mechanisms such as ice-shelf hydrofracturing and ice-cliff collapse may rapidly increase discharge from marine-based ice sheets. Here, we link a probabilistic framework for sea-level projections to a small ensemble of Antarctic ice-sheet (AIS) simulations incorporating these physical processes to explore their influence on global-mean sea-level (GMSL) and relative sea-level (RSL). We compare the new projections to past results using expert assessment and structured expert elicitation about AIS changes. Under high greenhouse gas emissions (Representative Concentration Pathway [RCP] 8.5), median projected 21st century GMSL rise increases from 79 to 146 cm. Without protective measures, revised median RSL projections would by 2100 submerge land currently home to 153 million people, an increase of 44 million. The use of a physical model, rather than simple parameterizations assuming constant acceleration of ice loss, increases forcing sensitivity: overlap between the central 90% of simulations for 2100 for RCP 8.5 (93–243 cm) and RCP 2.6 (26–98 cm) is minimal. By 2300, the gap between median GMSL estimates for RCP 8.5 and RCP 2.6 reaches >10 m, with median RSL projections for RCP 8.5 jeopardizing land now occupied by 950 million people (versus 167 million for RCP 2.6). The minimal correlation between the contribution of AIS to GMSL by 2050 and that in 2100 and beyond implies current sea-level observations cannot exclude future extreme outcomes. The sensitivity of post-2050 projections to deeply uncertain physics highlights the need for robust decision and adaptive management frameworks.

Plain Language Summary
Recent ice-sheet modeling papers have introduced new physical mechanisms—specifically the hydrofracturing of ice shelves and the collapse of ice cliffs—that can rapidly increase ice-sheet mass loss from a marine-based ice-sheet, as exists in much of Antarctica. This paper links new Antarctic model results into a sea-level rise projection framework to examine their influence on global and regional sea-level rise projections and their associated uncertainties, the potential impact of projected sea-level rise on areas currently occupied by human populations, and the implications of these projections for the ability to constrain future changes from present observations. Under a high greenhouse gas emission future, these new physical processes increase median projected 21st century GMSL rise from ∼80 to ∼150 cm. Revised median RSL projections for a high-emissions future would, without protective measures, by 2100 submerge land currently home to more than 153 million people. The use of a physical model indicates that emissions matter more for 21st century sea-level change than previous projections showed. Moreover, there is little correlation between the contribution of Antarctic to sea-level rise by 2050 and its contribution in 2100 and beyond, so current sea-level observations cannot exclude future extreme outcomes."

[AbruptSLR]

The linked reference offers a useful methodology for quantifying the influence of the SLR fingerprint effect on coastal localities:

Jerry X. Mitrovica et al. (13 December 2017), "Quantifying the Sensitivity of Sea Level Change in Coastal Localities to the Geometry of Polar Ice Mass Flux", Journal of Climate, https://doi.org/10.1175/JCLI-D-17-0465.1

http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-17-0465.1?utm_content=buffer76497&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer

Abstract: "It has been known for over a century that melting of individual ice sheets and glaciers drives distinct geographic patterns, or fingerprints, of sea-level change, and recent studies have highlighted the implications of this variability for hazard assessment and inferences of meltwater sources. These studies have computed fingerprints using simplified melt geometries, and a more generalized treatment would be advantageous when assessing or projecting sea-level hazards in the face of quickly evolving patterns of ice mass flux. We have inverted the usual fingerprint approach to compute site-specific sensitivity kernels for a global database of coastal localities. These kernels provide a mapping between geographically variable mass flux across each ice sheet and glacier and the associated static sea-level change at a given site. We highlight kernels for a subset of sites associated with melting from Greenland, Antarctica and the Alaska-Yukon-British Columbia glacier system. The latter, for example, reveal an under-appreciated sensitivity of ongoing and future sea level change along the US west coast to the geometry of ice mass flux in the region. Finally, we illustrate the practical utility of these kernels by computing sea-level predictions at a suite of sites associated with annual variability in Greenland ice mass since 2003 constrained by satellite gravity measurements."

[AbruptSLR]

The linked video provides a convenient summary, including for: Robert E. Kopp, Robert M. DeConto, Daniel A. Bader, Carling C. Hay, Radley M. Horton, Scott Kulp, Michael Oppenheimer, David Pollard & Benjamin H. Strauss (14 December 2017), "Evolving Understanding of Antarctic Ice-Sheet Physics and Ambiguity in Probabilistic Sea-Level Projections", Earth's Future, DOI: 10.1002/2017EF000663

Title: "2017 Fall Meeting Press Conference: The melting cryosphere"



Extract: "Earth’s frozen places are changing dramatically due to climate change. In this briefing, new research about shrinking glaciers and ice sheets, and the hazards of melting permafrost and sea level rise, will be presented."

[Sigmetnow]

Sea Level Rise Is Creeping into Coastal Cities. Saving Them Won’t Be Cheap.
Norfolk and Miami frequently see nuisance flooding now. The cost to protect them and other coastal cities in the future is rising with the tide.

...
- By the time the waters rise 14 inches, what's now a once-in-five-years coastal flood will come five times a year, a recent government study determined. By 2060, the number of coastal communities facing chronic flooding from rising seas could double to about 180, even if we rapidly cut emissions, according to a study by the Union of Concerned Scientists. If we don't slash emissions, that number could be 360.

- The costs from this inundation will be tremendous. One study, published in the journal Science in June, found that rising seas and more powerful tropical storms will cost the nation an additional 0.5 percent of GDP annually by 2100. Another, by the real estate firm Zillow, estimated that a rise of 6 feet by 2100 would inundate nearly 1.9 million homes worth a combined $882 billion.

- Estimating what it would cost to avoid some of this is trickier. It will certainly be expensive—look no further than Norfolk's $1.8 billion—but some research indicates it may be less costly than failing to act. An analysis by NRDC found that buying out low- and middle-income owners of single-family homes that repeatedly flood could save the National Flood Insurance Program between $20 billion and $80 billion by 2100.

- The Trump administration, however, has revoked or withdrawn at least six federal programs or orders intended to help make the nation's infrastructure more resilient to rising seas and climate change. That includes an executive order signed by President Barack Obama in 2015 that expanded the federal floodplain to account for climate change projections and limited or controlled any federal infrastructure spending within that zone. Trump revoked the order in August. Trump also disbanded a panel that was trying to help cities adapt to climate change.
...

https://insideclimatenews.org/news/28122017/sea-level-rise-coastal-cities-flooding-2017-year-review-miami-norfolk-seawall-cost

[Shared Humanity]

These kinds of announcements will become routine over the next 2 decades, occurring so frequently that they will no longer be picked up by national news networks but make only local headlines.

https://www.bloomberg.com/news/articles/2017-12-22/louisiana-sinking-fast-prepares-to-empty-out-its-coastal-plain

We have begun the massive relocation of hundreds of millions of humans from rising seas. Miami will not survive the century. Neither will Norfolk, Virginia.

[Alexander555]

China just developed a social security for every citizen. That will benefit a large part from Asia. And that means that the carbon footprint of the average asian is going to get bigger fast. That's 4,5 billion people that for the moment only have a carbon footprint that is just a fraction of the western footprint. 16 tonnes for the US per capita, 7,7 tonnes for China per capita, 1,9 tonnes for India per capita..... India for example is already building, or the documents are ready for 600 coal fired powerplants.

[Sigmetnow]

Rising sea swamps island along Bengal coast
Around 1.5 million people will be displaced in the Sundarbans, and the process has started

At one edge of the Sundarbans – the world’s largest mangrove forest – Mousuni used to have an embankment along Baliara to hold back the rising sea. That collapsed during the 2009 Cyclone Aila. Since then, there have been three attempts to build sea walls, all of which have collapsed against the power of the sea. Scientists say seas around the world are rising due to climate change, but the Bay of Bengal is rising twice as fast as the global average. ...

https://www.thethirdpole.net/2018/01/15/rising-sea-swamps-island-along-bengal-coast/

[AbruptSLR]

To me the following represents a lower bound assessment of SLR this coming century:

R. S. Nerem, B. D. Beckley, J. T. Fasullo, B. D. Hamlington, D. Masters and G. T. Mitchum (February 12, 2018), "Climate-change–driven accelerated sea-level rise detected in the altimeter era", PNAS, https://doi.org/10.1073/pnas.1717312115

http://www.pnas.org/content/early/2018/02/06/1717312115

Significance

Satellite altimetry has shown that global mean sea level has been rising at a rate of ∼3 ± 0.4 mm/y since 1993. Using the altimeter record coupled with careful consideration of interannual and decadal variability as well as potential instrument errors, we show that this rate is accelerating at 0.084 ± 0.025 mm/y2, which agrees well with climate model projections. If sea level continues to change at this rate and acceleration, sea-level rise by 2100 (∼65 cm) will be more than double the amount if the rate was constant at 3 mm/y.

Abstract

Using a 25-y time series of precision satellite altimeter data from TOPEX/Poseidon, Jason-1, Jason-2, and Jason-3, we estimate the climate-change–driven acceleration of global mean sea level over the last 25 y to be 0.084 ± 0.025 mm/y2. Coupled with the average climate-change–driven rate of sea level rise over these same 25 y of 2.9 mm/y, simple extrapolation of the quadratic implies global mean sea level could rise 65 ± 12 cm by 2100 compared with 2005, roughly in agreement with the Intergovernmental Panel on Climate Change (IPCC) 5th Assessment Report (AR5) model projections.

[sidd]

Nerem has been working on this for a while, and now claims to have isolated a quadratic term in sea level rise. The difficulty is that he had to remove the effects of pinatubo and el nino using climate models before he could isolate the quadratic term. I think as the length of the data record increase the acceleration will become more clearly visible and convincing.

I agree that his estimate is conservative, since as I have posted before, SLR is episodic rather than a smooth curve as is seen clearly in Blanchon(2009).

sidd

[wolfpack513]

New Jason-3 data through January 5.   60-day mean has now been above the linear trend for 3 years and counting. The 2016 peak was obviously Niño related but no regressing back to the mean, even with cool ENSO/La Niña conditions the last 18 months.

[RikW]

Just read in the dutch news that sea lvl rise is accelarting and 76cm is expected by the end of the century ánd that it will rise by 1 cm/year around 2100, according to a study done by NASA.

Bad news for a lot of coastal regions...

[gerontocrat]

New Jason-3 data through January 5.   60-day mean has now been above the linear trend for 3 years and counting. The 2016 peak was obviously Niño related but no regressing back to the mean, even with cool ENSO/La Niña conditions the last 18 months.

Stupid question?

The graphs show impressive correlation between spikes in sea level rise and El Nino events, and also drops in sea level rise with La Nina events.

BUT, during La Nina years the oceans are gobbling up more heat, and in El Nino years releasing heat to the atmosphere (2016 saw a drop in ocean heat content). Heat expands water and the literature says(?) half of sea level rise is due to expansion of the water in the oceans.

Does this mean that in El Nino years increased melting of ice caps exceeds slow down of increases (and even drops) in Ocean heat content ?

[charles_oil]

RikW - Link for Nasa Goddard report & video   https://svs.gsfc.nasa.gov/12849  or click video link below if it works!

Sea Level Rise Accelerates Over Time
 
Global sea level rise is accelerating incrementally over time rather than increasing at a steady rate, as previously thought, according to a new study based on 25 years of NASA and European satellite data. If the rate of ocean rise continues to change at this pace, sea level will rise 26 inches (65 centimeters) by 2100--enough to cause significant problems for coastal cities.

Charles

[wolfpack513]

New Jason-3 data through January 5.   60-day mean has now been above the linear trend for 3 years and counting. The 2016 peak was obviously Niño related but no regressing back to the mean, even with cool ENSO/La Niña conditions the last 18 months.

Stupid question?

The graphs show impressive correlation between spikes in sea level rise and El Nino events, and also drops in sea level rise with La Nina events.

BUT, during La Nina years the oceans are gobbling up more heat, and in El Nino years releasing heat to the atmosphere (2016 saw a drop in ocean heat content). Heat expands water and the literature says(?) half of sea level rise is due to expansion of the water in the oceans.

Does this mean that in El Nino years increased melting of ice caps exceeds slow down of increases (and even drops) in Ocean heat content ?

Global temperature lags Niño 3.4 by about 3 months. So the steep increase in GMSL follows the Niño as its strengthening. You’ll notice that the steepest slope is the middle of 2015 on the chart above.  Global temperature spiked in February of 2016.

[jai mitchell]

New Jason-3 data through January 5.   60-day mean has now been above the linear trend for 3 years and counting. The 2016 peak was obviously Niño related but no regressing back to the mean, even with cool ENSO/La Niña conditions the last 18 months.

Stupid question?

The graphs show impressive correlation between spikes in sea level rise and El Nino events, and also drops in sea level rise with La Nina events.

BUT, during La Nina years the oceans are gobbling up more heat, and in El Nino years releasing heat to the atmosphere (2016 saw a drop in ocean heat content). Heat expands water and the literature says(?) half of sea level rise is due to expansion of the water in the oceans.

Does this mean that in El Nino years increased melting of ice caps exceeds slow down of increases (and even drops) in Ocean heat content ?

The ENSO fluctuations in sea level have more to do with changing rainfall patterns on land vs. on ocean than anything else.

http://www.tandfonline.com/doi/abs/10.1080/01490419.2012.718209

[Gray-Wolf]

I'm thinking all of this is based on the middle ground and does not respect any of the 'fat tail' results?
All we see , year after year, are extreme events outpacing what we 'expected' in the mid line runs?

Maybe we need take a look at 'doubling times' for ice loss /sea level changes?

I seem to remember some eastern gent asking an emperor for payment in rice on a chess board?

Doubling every square....

If doubling times are reducing we are in big trouble.....

[Daniel B.]

This does appear to fall more in the fat tail than middle ground.  They project a tripling if SLR by the end of the century.  This is higher than the IPCC and many others.

[AbruptSLR]

Here is the U of Colorado's SLR plot through the beginning of 2018, and I note that we are currently towards the end of a double-dip La Nina event, but SLR is still well above the trend line:

[Gray-Wolf]

I worry folk spent far too much energy trying to show Deniers why sea ice extent was growing rather than considering the speed of change once the ozone hole began to mens and Pacific drivers swung into ADW augmentation phase.

Well here we are.

So how may years does P.I.G./Thwaites before that slip back of their current grounding line and how fast will that retreat prove to be ( never mind the next 2012 across Greenland?)

I seem to recall 'doubling times' had fallen below 10 years in the noughties? Can anyone out there confirm/dismiss this please?

[Stephen]

New Jason-3 data through January 5.   60-day mean has now been above the linear trend for 3 years and counting. The 2016 peak was obviously Niño related but no regressing back to the mean, even with cool ENSO/La Niña conditions the last 18 months.

Stupid question?

The graphs show impressive correlation between spikes in sea level rise and El Nino events, and also drops in sea level rise with La Nina events.

BUT, during La Nina years the oceans are gobbling up more heat, and in El Nino years releasing heat to the atmosphere (2016 saw a drop in ocean heat content). Heat expands water and the literature says(?) half of sea level rise is due to expansion of the water in the oceans.

Does this mean that in El Nino years increased melting of ice caps exceeds slow down of increases (and even drops) in Ocean heat content ?

The ENSO fluctuations in sea level have more to do with changing rainfall patterns on land vs. on ocean than anything else.

http://www.tandfonline.com/doi/abs/10.1080/01490419.2012.718209

La Nina means lots of rain in outback Australia. When the Murray-Darling basin floods the subsequent inland sea can absorb a lot of water, enough to effect sea-levels.

[wolfpack513]

I don't disagree that the changes in rainfall with ENSO and its impact on GMSL, especially La Niña. Though you could argue that the 2010-2011 event & its Australia rain was an extreme event.   However, the build up of OHC in El Niños does impact GMSL.  That's why the steepest slope on the CU chart is in early 2015 well before the strongest atmospheric response.

[gerontocrat]

Thanks for the responses re Ocean Heat, La Nina and El Nino. A bit more understanding of the complex interactions is always a pleasure. I had forgotten about that amazing Australian rainfall event.

[gerontocrat]

With JAXA on holiday today, I activated a promise I made myself and drag out sea level rise data from NASA and bunged it into a simple X-Y graph. N.B. NOT NASA's projections

Note the impressive R² correlation of more than 0.98 on the graph below. I wonder how good the correlation is with CO₂ ppm. Anybody got a link to the detailed data that AbruptSLR (?) uses for his super CO2  ppm month by month graph ?

[gerontocrat]

I found a link to the detailed data that AbruptSLR uses for his super CO2  ppm month by month graph. So below the first graph compares sea level rise in millimetres with CO2 concentrations in ppm.

An impressive correlation. If the polynomial is increased to an x3 equation up goes the sea level increase. See second graph.

The third graph is a CO2 graph with a pessimistic (impossible?) projection of CO2 increases to 2030.
Lies, damned Lies and Statistics ?

The graph below shows CO2 ppm reaching 450 ppm by 2030 using a polynomial trend line at the 4th power.
y = 7E-06x4 - 0.0587x3 + 175.04x2 - 232014x + 1E+08
R² = 0.9936

Note the ridiculously high R2 correlation. In other words, at first sight plausible. This would require CO2 concentration to increase by about 40 ppm in 13 years, i.e. just over 3 ppm per annum, as opposed to the current increase per annum of just over 2. Increase in human CO2 emissions on this sort of scale does not seem plausible. So such a marked increase in CO2 ppm per annum would require a significant collapse in the carbon sinks (possible?) and / or large CO2 emissions from new sources, e.g. cleared rainforest peatlands (possible?).

So to my surprise, 450 ppm by 2030 may be unlikely, but definitely possible?

This would not do sea levels a lot of good if the relationship between sea level and CO2 ppm remained valid.

[Shared Humanity]

With JAXA on holiday today, I activated a promise I made myself and drag out sea level rise data from NASA and bunged it into a simple X-Y graph. N.B. NOT NASA's projections

Note the impressive R² correlation of more than 0.98 on the graph below. I wonder how good the correlation is with CO₂ ppm. Anybody got a link to the detailed data that AbruptSLR (?) uses for his super CO2  ppm month by month graph ?

First, we need to look at the data. Do we believe it is accurate or are there measurement errors that call it into question? I don't know the answer to this question but it seems unlikely that measurement error would correlate so readily.

I think we need to conclude that sea level rise is accelerating. We already know glaciers are accelerating and ablating more rapidly, Greenland melt is accelerating etc. I would argue that this acceleration will continue and we will arrive at sea levels in 2100 which will shock us.

[AbruptSLR]

In my opinion the linked reference errs significantly (/dangerously) on the side of least drama, but I provide this information for those who are interested:

Matthias Mengel et al (2018), "Committed sea-level rise under the Paris Agreement and the legacy of delayed mitigation action", Nature Communications, volume 9, Article number: 601, doi:10.1038/s41467-018-02985-8

http://www.nature.com/articles/s41467-018-02985-8

Abstract: "Sea-level rise is a major consequence of climate change that will continue long after emissions of greenhouse gases have stopped. The 2015 Paris Agreement aims at reducing climate-related risks by reducing greenhouse gas emissions to net zero and limiting global-mean temperature increase. Here we quantify the effect of these constraints on global sea-level rise until 2300, including Antarctic ice-sheet instabilities. We estimate median sea-level rise between 0.7 and 1.2 m, if net-zero greenhouse gas emissions are sustained until 2300, varying with the pathway of emissions during this century. Temperature stabilization below 2 °C is insufficient to hold median sea-level rise until 2300 below 1.5 m. We find that each 5-year delay in near-term peaking of CO2 emissions increases median year 2300 sea-level rise estimates by ca. 0.2 m, and extreme sea-level rise estimates at the 95th percentile by up to 1 m. Our results underline the importance of near-term mitigation action for limiting long-term sea-level rise risks."

[AbruptSLR]

More paleo data on sea level changes over the past 6,000 years::

N.D. Leonard et al. New evidence for "far-field" Holocene sea level oscillations and links to global climate records, Earth and Planetary Science Letters (2018). DOI: 10.1016/j.epsl.2018.02.008

https://www.sciencedirect.com/science/article/pii/S0012821X18300645?via%3Dihub

Abstract: "Rising sea level in the coming century is of significant concern, yet predicting relative sea level change in response to eustatic sea level variability is complex. Potential analogues are provided by the recent geological past but, until recently, many sea level reconstructions have been limited to millennial scale interpretations due to age uncertainties and paucity in proxy derived records. Here we present a sea level history for the tectonically stable “far-field” Great Barrier Reef, Australia, derived from 94 high precision uranium–thorium dates of sub-fossil coral microatolls. Our results provide evidence for at least two periods of relative sea level instability during the Holocene. These sea level oscillations are broadly synchronous with Indo-Pacific negative sea surface temperature anomalies, rapid global cooling events and glacial advances. We propose that the pace and magnitude of these oscillations are suggestive of eustatic/thermosteric processes operating in conjunction with regional climatic controls."

[bligh8]

AVISO…Jason 3, 2016-2018, seasonal single not removed....5.65mm

[Daniel B.]

+/- 4.4

[Archimid]

A bit of dark humor.

[oren]

A bit of dark humor.

Indeed. Irony at its finest.

[AbruptSLR]

While I believe that the linked reference errs on the side of least drama, I provide a link for those who are interested:

Rasmussen et al. (2018), "Extreme sea level implications of 1.5 °C, 2.0 °C, and 2.5 °C temperature stabilization targets in the 21st and 22nd centuries", Environ. Res. Lett. 13, https://doi.org/10.1088/1748-9326/aaac87

http://iopscience.iop.org/article/10.1088/1748-9326/aaac87/meta

Abstract: "Sea-level rise (SLR) is magnifying the frequency and severity of extreme sea levels (ESLs) that can cause coastal flooding. The rate and amount of global mean sea-level (GMSL) rise is a function of the trajectory of global mean surface temperature (GMST). Therefore, temperature stabilization targets (e.g. 1.5 °C and 2.0 °C of warming above pre-industrial levels, as from the Paris Agreement) have important implications for coastal flood risk. Here, we assess, in a global network of tide gauges, the differences in the expected frequencies of ESLs between scenarios that stabilize GMST warming at 1.5 °C, 2.0 °C, and 2.5 °C above pre-industrial levels. We employ probabilistic, localized SLR projections and long-term hourly tide gauge records to estimate the expected frequencies of historical and future ESLs for the 21st and 22nd centuries. By 2100, under 1.5 °C, 2.0 °C, and 2.5 °C GMST stabilization, the median GMSL is projected to rise 48 cm (90% probability of 28–82 cm), 56 cm (28–96 cm), and 58 cm (37–93 cm), respectively. As an independent comparison, a semi-empirical sea level model calibrated to temperature and GMSL over the past two millennia estimates median GMSL rise within 7–8 cm of these projections. By 2150, relative to the 2.0 °C scenario and based on median sea level projections, GMST stabilization of 1.5 °C spares the inundation of lands currently home to about 5 million people, including 60 000 individuals currently residing in Small Island Developing States. We quantify projected changes to the expected frequency of historical 10-, 100-, and 500-year ESL events using frequency amplification factors that incorporate uncertainty in both local SLR and historical return periods of ESLs. By 2150, relative to a 2.0 °C scenario, the reduction in the frequency amplification of the historical 100 year ESL event arising from a 1.5 °C GMST stabilization is greatest in the eastern United States, with ESL event frequency amplification being reduced by about half at most tide gauges. In general, smaller reductions are projected for Small Island Developing States."

[oren]

This one is seriously ESLD.

[Shared Humanity]

With a warming pole causing more violent and frequent Nor'easters along the east coast of the U.S., the permanent destruction of the coastlines (barrier islands, beaches etc) has now been set in motion. This destruction is ongoing and in 20 years we will not recognize the coastline.

Think this is an exaggeration? Hurricane Sandy resulted in three federal agencies remapping sections of the east coast so that the maps reflect the permanently altered coastline.

http://www.noaanews.noaa.gov/stories2013/20130820_sandymapping.html

This is getting serious and will only get worse.

Never mind whether we will be able to repair the coastline damage caused by sea level rise and more violent storms. (We aren't able to do this now.) We will know we are in real trouble when we can no longer remap the coastline as quickly as it is altered.

[Daniel B.]

Not to mention revealing old railroad tracks that have been submerged on the Jersey coast.

https://weather.com/news/weather/video/noreasters-reveal-train-tracks-buried-under-new-jersey-beach

[Shared Humanity]

We will continue to invest large sums of money to harden the coastline in order to protect our cities. As a wealthy country we are able to do this. Eventually we will need to abandon large portions of them.

What you will see is strategic retreat, making hard choices to protect some areas while vacating others. This is already occurring on the Louisiana coast.

It won't be until the end of this century that strategic retreat looks like a mass exodus of biblical proportions.....I hope.

[Shared Humanity]

13 years after Hurricane Katrina, large sections of the 9th ward of New Orleans, the largest ward in the city, remain a wasteland. It will never be rebuilt.

https://www.huffingtonpost.com/entry/new-orleans-urban-decay_us_57c05e53e4b085c1ff2910ab

Vast stretches of the U.S. coastline are just one category 5 hurricane away from suffering a similar fate. It is one thing to invest hundreds of millions of dollars to protect billions of dollars of valuable real estate. It is quite another to spend billions of dollars to rebuild on vulnerable land after it has been destroyed.

The population of New Orleans in 2004 was 462 thousand. Today 396 thousand live in the city.

[Daniel B.]

13 years after Hurricane Katrina, large sections of the 9th ward of New Orleans, the largest ward in the city, remain a wasteland. It will never be rebuilt.

https://www.huffingtonpost.com/entry/new-orleans-urban-decay_us_57c05e53e4b085c1ff2910ab

Vast stretches of the U.S. coastline are just one category 5 hurricane away from suffering a similar fate. It is one thing to invest hundreds of millions of dollars to protect billions of dollars of valuable real estate. It is quite another to spend billions of dollars to replace real estate on vulnerable land after it has been destroyed.

The population of New Orleans in 2004 was 462 thousand. Today 396 thousand live in the city.

New Orleans was a situation waiting to happen.  Much of the city is below sea level and built on sediment.  Not to mention poor infrastructure and upkeep.  Katrina was just the final straw.  Other citiies are highly unlikely to suffer a similar fate.

[Shared Humanity]

13 years after Hurricane Katrina, large sections of the 9th ward of New Orleans, the largest ward in the city, remain a wasteland. It will never be rebuilt.

https://www.huffingtonpost.com/entry/new-orleans-urban-decay_us_57c05e53e4b085c1ff2910ab

Vast stretches of the U.S. coastline are just one category 5 hurricane away from suffering a similar fate. It is one thing to invest hundreds of millions of dollars to protect billions of dollars of valuable real estate. It is quite another to spend billions of dollars to replace real estate on vulnerable land after it has been destroyed.

The population of New Orleans in 2004 was 462 thousand. Today 396 thousand live in the city.

New Orleans was a situation waiting to happen.  Much of the city is below sea level and built on sediment.  Not to mention poor infrastructure and upkeep.  Katrina was just the final straw.  Other citiies are highly unlikely to suffer a similar fate.

Bullshit. Large sections of the Miami metro area flood during high tide on sunny days. A direct hit from a category 5 will cause areas to be permanently abandoned.

"New Orleans was a situation waiting to happen."

My point exactly. Much of the US coastline is a situation waiting to happen. And each time a situation happens, the same decisions will be made. Some areas will never be rebuilt

[Daniel B.]

13 years after Hurricane Katrina, large sections of the 9th ward of New Orleans, the largest ward in the city, remain a wasteland. It will never be rebuilt.

https://www.huffingtonpost.com/entry/new-orleans-urban-decay_us_57c05e53e4b085c1ff2910ab

Vast stretches of the U.S. coastline are just one category 5 hurricane away from suffering a similar fate. It is one thing to invest hundreds of millions of dollars to protect billions of dollars of valuable real estate. It is quite another to spend billions of dollars to replace real estate on vulnerable land after it has been destroyed.

The population of New Orleans in 2004 was 462 thousand. Today 396 thousand live in the city.

New Orleans was a situation waiting to happen.  Much of the city is below sea level and built on sediment.  Not to mention poor infrastructure and upkeep.  Katrina was just the final straw.  Other citiies are highly unlikely to suffer a similar fate.

Bullshit. Large sections of the Miami metro area flood during high tide on sunny days. A direct hit from a category 5 will cause areas to be permanently abandoned.

"New Orleans was a situation waiting to happen."

My point exactly. Much of the US coastline is a situation waiting to happen. And each time a situation happens, the same decisions will be made. Some areas will never be rebuilt

And how much of Miami remains a wasteland?  Exactly!  You have no evidence to support your claims, but are relying on sensationalism.  Any city taking a direct hit from a category 5 storm will experience severe destruction.  Miami rebuilt after category 5 Andrew in 1992.  That is part of the cost of building in a hurricane area.  Nothing has changed.  I rest my case!

[Archimid]

Any city taking a direct hit from a category 5 storm will experience severe destruction.  Miami rebuilt after category 5 Andrew in 1992.

Yeah. Don't you know that rebuilding is automatic and we can always depend on it? Regardless of how bad it gets we'll be able to rebuild. It doesn't matter if high intensity hurricanes increase in frequency, we can always print more money and rebuild.

That is part of the cost of building in a hurricane area.

And that cost is fixed. An increase in extreme weather should have no effect in that cost so it can safely be ignored.

Nothing has changed

Nothing except the increase in high intensity hurricanes,  increase in 1-100 year floods, increase in intensity and distribution of fires, increase in flash droughts etc.  But I guess we can ignore that because we were able to adjust when the rate of disasters was lower. That means that without a doubt we'll be able to adjust as their frequency increases.

I rest my case!

Wow you are so brave. Nothing scares you. Not even real danger. I want to be like you. Here I am thinking that the increase in extreme events will cost billions of dollars and who knows how many lives, when I can just pretend the increase in events will have no effect. Thanks for your service. You are a hero. /salute
/s

I do wonder though, what if you are wrong? What if there are reasons to be afraid? What if the magical GDP fails in restoring everything nature takes away? Will you admit to your family your part in downplaying the dangers or will you just be as brave as you pretend to be now and pretend you had no part in slowing down the prevention of climate change? You seem so darn sure and confident in the face of so much evidence that contradicts you. Do you even allow a for small possibility of climate change being bad or have you completely ruled it out?

[SteveMDFP]

And how much of Miami remains a wasteland?  Exactly!  You have no evidence to support your claims, but are relying on sensationalism.  Any city taking a direct hit from a category 5 storm will experience severe destruction.  Miami rebuilt after category 5 Andrew in 1992.  That is part of the cost of building in a hurricane area.  Nothing has changed.  I rest my case!

Many things have changed.  In terms of whether rebuilding happens after a disaster, a critical factor is insurance costs.  If insurers conclude that there's an increasing risk of repeated disasters, premiums rise, perhaps dramatically.  If so, the rebuilding only happens on higher ground.

Insurance isn't the only issue, just the most obvious.  Municipalities face heavy EPA fines when sewage systems flood.  As flooding becomes more frequent, local taxes rise, new sewage infrastructure has to be built.  But the rebuilt infrastructure itself faces increased insurance costs.  These things can have a synergistic effect with each other.   Who wants to build a house or business where there's no economic activity going on?

[Daniel B.]

No argument regarding the financial decisions to rebuild.  That will always occur.  Business issues, governmental regulations, etc. are a completely difference set of problems that will always affect these decisions, and are often changing.  Rarely does rebuilding equate to building the same structure that existed previously.  On this we can agree.

[Archimid]

No argument regarding the financial decisions to rebuild.  That will always occur.  Business issues, governmental regulations, etc. are a completely difference set of problems that will always affect these decisions, and are often changing.  Rarely does rebuilding equate to building the same structure that existed previously.  On this we can agree.

Do you even allow a for small possibility of climate change being bad or have you completely ruled it out?

[gerontocrat]

There is an economic argument that fixing things that are broken is good as it increases economic activity. This was shot down many years ago - the example used was a window broken by a kid's bad throw with a baseball. It is called the opportunity cost of capital. If capital, a limited resource, is used merely to replace a broken window it cannot be used for something else which would create added value, or real wealth.

Rebuilding Miami post 1992 fixed nothing. The USA spends tens of millions of dollars a year digging up sand to replenish  eroded beaches knowing in a year or two it has to be done again..  It is called the inefficient allocation of capital resources - to you and me a waste of money.

It is true that at the moment damage from AGW is only scratching and denting the economies of OECD countries. That perhaps is the problem. New Orleans got away with neglect of its defences for many years until Katrina. New Orleans is now a smaller place and away from the shiny new centre a worse place. Is that the fate of many other places ?

[Sigmetnow]

Every year, the average American emits enough CO2 to ultimately melt about 10,000 tons of the Antarctic ice sheet, adding another 10,000 cubic meters of water to the oceans.
- Ken Caldeira

How much ice is melted by each carbon dioxide emission?

Each American emits on average about 16 tons of CO2 to the atmosphere each year, primarily from the burning of coal, oil and gas, and atmospheric release of the resulting waste CO2.

This works out to about 1.8 kg (about 4 pounds) of CO2 per hour per American. This is more than twice the per capita emission rate of Europe and about twenty times the per capita emission rate for sub-Saharan Africa.

If I am an average American, the CO2 emissions that I produce each year (by participating in the broader economy) will be responsible for melting about 10,000 tons of Antarctic ice, adding about 10,000 cubic meters of fresh water to the volume of the oceans.

That works out to about more than a ton of Antarctic ice loss for each hour of CO2 emissions from an average American. Every minute, we emit enough CO2 to add another five gallons of water to the oceans through glacial ice melt.

If you do the units conversion, this means that each American on average emits enough CO2 every 3 seconds to ultimately add about another liter of water to the oceans. The Europeans emit enough CO2 to add another liter to sea-level rise every 8 seconds, and the sub-Saharan Africans add a liter of seawater’s worth of CO2 emissions every minute. ...

https://kencaldeira.wordpress.com/2018/03/24/how-much-ice-is-melted-by-each-carbon-dioxide-emission/