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Archimid

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #700 on: April 21, 2017, 03:21:49 PM »
State of emergency declared for Louisiana coast by Gov. John Bel Edwards

http://www.nola.com/environment/index.ssf/2017/04/state_of_emergency_louisiana_coast.html

Gov. John Bel Edwards on Wednesday (April 19) officially declared Louisiana's coastal land loss an emergency, a move he hopes will expedite a host of restoration projects mired in federal permitting. "The Louisiana coast is in a state of crisis that demands immediate and urgent action to avert further damage to one of our most vital resources," he said.
I am an energy reservoir seemingly intent on lowering entropy for self preservation.

gerontocrat

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #701 on: April 21, 2017, 03:52:54 PM »
On the left the official Louisiana Coastline; on the right reality.
"Para a Causa do Povo a Luta Continua!"

TerryM

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #702 on: April 21, 2017, 04:51:54 PM »
A Democratic governor asks a Republican President for funds to help with problems due to climate change.
A Rabbi, a Priest, and a Reverend walk into a bar.


Which will elicit more laughs?


Terry

Shared Humanity

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #703 on: April 22, 2017, 03:11:42 PM »
Simple little article making a simple little point....the financial system, the foundation of capitalism, will not be able to withstand the impact of rising sea levels in southeast Florida and this little story will be playing out across the country and world.

https://www.bloomberg.com/news/features/2017-04-19/the-nightmare-scenario-for-florida-s-coastal-homeowners

The difference between this unavoidable financial catastrophe from the housing crisis that tanked the world economy in 2007 is that there will be no recovery of the housing prices.

And this ignores completely the disastrous effects of other climate destruction of the real economy.

AbruptSLR

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #704 on: May 18, 2017, 07:50:06 PM »
While the linked reference may well err on the side of least drama it is a good first effort to quantify the impacts of potential abrupt sea level rise associated with ice-cliff failure and hydrofracting mechanisms:

Kopp et. al. (2017) "Implications of ice-shelf hydrofracturing and ice-cliff collapse mechanisms for sea-level projections", arXiv:1704.05597v1

https://arxiv.org/pdf/1704.05597.pdf

Abstract: "Probabilistic sea-level projections have not yet integrated insights from physical ice-sheet models representing mechanisms, such as ice-shelf hydrofracturing and ice-cliff collapse, that can rapidly increase ice-sheet discharge. Here, we link a probabilistic framework for sealevel projections to a small ensemble of Antarctic ice-sheet (AIS) simulations incorporating these physical processes to explore their influence on projections of global-mean sea-level (GMSL) and relative sea-level (RSL) change. Under high greenhouse gas emissions (Representative Concentration Pathway [RCP] 8.5), these physical processes increase median projected 21st century GMSL rise from ~80 cm to ~150 cm. Revised median RSL projections would, without protective measures, by 2100 submerge land currently home to > 79 million people, an increase of ~25 million people. The use of a physical model, rather than simple parameterizations assuming constant acceleration, increases sensitivity to forcing: overlap between the central 90% of the frequency distributions 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 ~900 million people (vs. ~80 million for RCP 2.6). There is little correlation between the contribution of AIS to GMSL by 2050 and that in 2100 and beyond, so current sea-level observations cannot exclude future extreme outcomes. These initial explorations indicate the value and challenges of developing truly probabilistic sea-level rise projections incorporating complex ice-sheet physics."
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Lennart van der Linde

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #705 on: May 18, 2017, 11:03:14 PM »
While the linked reference may well err on the side of least drama it is a good first effort to quantify the impacts of potential abrupt sea level rise associated with ice-cliff failure and hydrofracting mechanisms.

Thanks for the reference ASLR. Table 1 below, from Kopp et al 2017, shows the estimates with and without including the results of DC 16 (DeConto & Pollard 2016). RCP4.5 still has a 5% chance of 4.55m in 2200, and RCP2.6 a 5% chance of 2.06m in 2200.

Dry_Land_Is_Not_A_Myth

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #706 on: May 19, 2017, 01:29:40 AM »
What do the column labels mean (50, 17-83, 5-95, 1-99, 99.9)?

oren

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #707 on: May 19, 2017, 07:49:32 AM »
What do the column labels mean (50, 17-83, 5-95, 1-99, 99.9)?
Probability ranges.
Edit: Actually explained at the bottom of the table.

AbruptSLR

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #708 on: June 07, 2017, 07:41:44 PM »
New analysis on SLR (see image):

Sönke Dangendorf, Marta Marcos, Guy Wöppelmann, Clinton P. Conrad, Thomas Frederikse, and Riccardo Riva (2017, "Reassessment of 20th century global mean sea level rise", PNAS, doi: 10.1073/pnas.1616007114

http://www.pnas.org/content/114/23/5946.short

Abstract: "The rate at which global mean sea level (GMSL) rose during the 20th century is uncertain, with little consensus between various reconstructions that indicate rates of rise ranging from 1.3 to 2 mm⋅y−1. Here we present a 20th-century GMSL reconstruction computed using an area-weighting technique for averaging tide gauge records that both incorporates up-to-date observations of vertical land motion (VLM) and corrections for local geoid changes resulting from ice melting and terrestrial freshwater storage and allows for the identification of possible differences compared with earlier attempts. Our reconstructed GMSL trend of 1.1 ± 0.3 mm⋅y−1 (1σ) before 1990 falls below previous estimates, whereas our estimate of 3.1 ± 1.4 mm⋅y−1 from 1993 to 2012 is consistent with independent estimates from satellite altimetry, leading to overall acceleration larger than previously suggested. This feature is geographically dominated by the Indian Ocean–Southern Pacific region, marking a transition from lower-than-average rates before 1990 toward unprecedented high rates in recent decades. We demonstrate that VLM corrections, area weighting, and our use of a common reference datum for tide gauges may explain the lower rates compared with earlier GMSL estimates in approximately equal proportion. The trends and multidecadal variability of our GMSL curve also compare well to the sum of individual contributions obtained from historical outputs of the Coupled Model Intercomparison Project Phase 5. This, in turn, increases our confidence in process-based projections presented in the Fifth Assessment Report of the Intergovernmental Panel on Climate Change."
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Sigmetnow

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #709 on: June 08, 2017, 02:45:55 PM »
U.S.:  Report: Sea rise means more tidal flooding this year for New Jersey Shore
...
The NOAA data show that even without an El Niño, three of the local locations examined, Atlantic City and Sandy Hook in New Jersey and Philadelphia, have all shown a continual increase in nuisance flooding over the last 50 years.

“What I see for Atlantic City and Sandy is an acceleration in the number of days per year in high-tide flooding,” said NOAA’s Billy Sweet, one of the report’s authors. “It’s growing by leaps and bounds. That’s a concern, because ultimately this trend is going to have to be reconciled locally.”
...
http://www.philly.com/philly/health/report-sea-rise-means-more-tidal-flooding-this-year-for-jersey-shore-20170607.html
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Archimid

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #710 on: June 12, 2017, 12:09:05 AM »
Fantastic video, like all of Vice's reports. Great imagery and sound bites.

Shane Smith Investigates The True Cost of Climate Denial (VICE on HBO: Season 5, Episode 1)

https://youtu.be/9suO4jrwfDE

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Sigmetnow

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #711 on: June 12, 2017, 04:45:06 PM »
U.S.:  Resettling climate refugees from Louisiana
In January, the Department of Housing and Urban Development announced grants totaling $1 billion in 13 states to help communities adapt to climate change, by building stronger levees, dams and drainage systems.

One of those grants, $48 million for Isle de Jean Charles, is something new: the first allocation of federal tax dollars to move an entire community struggling with the impacts of climate change. The divisions the effort has exposed and the logistical and moral dilemmas it has presented point up in microcosm the massive problems the world could face in the coming decades as it confronts a new category of displaced people who have become known as climate refugees....
https://www.nytimes.com/2016/05/03/us/resettling-the-first-american-climate-refugees.html

Electrek says:
Resettling the First American ‘Climate Refugees’ – $48 million for Isle de Jean Charles, is something new: the first allocation of federal tax dollars to move an entire community struggling with the impacts of climate change – This is the definition of an externality. Fossil fuel sources were just given an extra $50 million for free. Taken from the American tax payer. This is part of the $5.3 trillion a year fossil fuels get annually.
https://electrek.co/2017/06/12/egeb-german-citizens-energy-company-omnio-sungrow-floating-solar-schneiderman/
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Sigmetnow

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #712 on: June 14, 2017, 01:07:19 PM »
Trump Tells Mayor Of Sinking U.S. Island Not To Worry About Climate Change
Scientists predict rising seas will soon swamp Virginia’s Tangier Island. The president doesn’t seem to believe it.
WASHINGTON — President Donald Trump, apparently confirming his disregard for the risks of global climate change, reportedly told the mayor of a small Chesapeake Bay island that could soon disappear to erosion and rising seas that there’s no cause for concern.

Trump phoned James “Ooker” Eskridge, the mayor of Tangier, Virginia, on Monday, a few days after CNN aired a story about the impacts of climate change on the island in the middle of the bay, The Daily Times in Salisbury, Maryland, reports.

Trump “said not to worry about sea-level rise,” Eskridge told the newspaper. “He said, ‘Your island has been there for hundreds of years, and I believe your island will be there for hundreds more.’”

It’s a bold claim, even for a longtime climate-change nonbeliever who has dismissed the phenomenon as “bullshit” and a Chinese “hoax.”

Since 1850, nearly 70 percent of Tangier’s landmass has been lost, according to a 2015 study by U.S. Army Corps of Engineers scientists. Those scientists predict that in as little as 25 years, erosion and rising seas will sink much of the remaining land, forcing residents to abandon their island homes....
http://www.huffingtonpost.com/entry/trump-tangier-island-mayor-climate-change_us_59406a8ce4b09ad4fbe3fa03
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pileus

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #713 on: June 14, 2017, 11:15:18 PM »
Trump Tells Mayor Of Sinking U.S. Island Not To Worry About Climate Change
Scientists predict rising seas will soon swamp Virginia’s Tangier Island. The president doesn’t seem to believe it.
WASHINGTON — President Donald Trump, apparently confirming his disregard for the risks of global climate change, reportedly told the mayor of a small Chesapeake Bay island that could soon disappear to erosion and rising seas that there’s no cause for concern.

Trump phoned James “Ooker” Eskridge, the mayor of Tangier, Virginia, on Monday, a few days after CNN aired a story about the impacts of climate change on the island in the middle of the bay, The Daily Times in Salisbury, Maryland, reports.

Trump “said not to worry about sea-level rise,” Eskridge told the newspaper. “He said, ‘Your island has been there for hundreds of years, and I believe your island will be there for hundreds more.’”

It’s a bold claim, even for a longtime climate-change nonbeliever who has dismissed the phenomenon as “bullshit” and a Chinese “hoax.”

Since 1850, nearly 70 percent of Tangier’s landmass has been lost, according to a 2015 study by U.S. Army Corps of Engineers scientists. Those scientists predict that in as little as 25 years, erosion and rising seas will sink much of the remaining land, forcing residents to abandon their island homes....
http://www.huffingtonpost.com/entry/trump-tangier-island-mayor-climate-change_us_59406a8ce4b09ad4fbe3fa03


Was just about to post this.  It's a great example of Trump encountering a very specific implication of not only climate change impact but also scientifically based geologic processes.  He fails on both subject areas.

The lower Chesapeake Bay has been undergoing subsidence for thousands of years, and that whole region will be among the first in the US to be devastated by rising sea levels given the exiting geologic factors.

Have visited Tangier several times.  Beautiful area, very rough and ready, salt of the earth people.  Poor folk are being fed lies by their mayor and Trump.

Sigmetnow

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #714 on: June 20, 2017, 06:07:53 PM »
New York City Planners With Sandy Nightmares Say Barrier May Come Too Late
The warming Atlantic Ocean has raised the risk of another Hurricane Sandy. And still, trillions of dollars of real estate and infrastructure near the shores of New York City and northern New Jersey remain vulnerable to devastation.

A storm-surge barrier similar to those in Louisiana and parts of Europe might protect the area, but politicians have questioned its $30 billion cost, effectiveness and environmental impact. A group of scientists, planners and property owners is urging the U.S. Army Corps of Engineers to accelerate its study of the project. It may take another hurricane to speed up the process....
https://www.bloomberg.com/news/articles/2017-06-20/nyc-planners-with-sandy-nightmares-say-barrier-may-come-too-late
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Dry_Land_Is_Not_A_Myth

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #715 on: June 21, 2017, 03:08:49 PM »


Latest MSL data from March 2017. Any thoughts/explanations on why MSL has been flat for over a year? Seems incredulous due to all the melting of Greenland and Antarctica? Could it be related to in the influx of colder water reducing the thermal expansion effects?

wehappyfew

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #716 on: June 21, 2017, 03:48:01 PM »
El Nino changes precipitation patterns. Less rain over South America, more over the ocean. Sea level rises.

Neutral/weak La Nina since mid 2016 = more rain over land, sea level rise is temporarily paused.

rboyd

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #717 on: June 21, 2017, 05:24:28 PM »
You can see the relative flat-lining after the 1998 El Nino. Interesting that apart from that El Nino the trend does not have that much noise/variability in it until 2010, then it gets much noisier. Perhaps with more and more water vapour in the atmosphere we should expect this?

oren

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #718 on: June 21, 2017, 05:29:13 PM »
It's basically reversion to mean, post el-nino. But perhaps there's also the higher Greenland mass balance this year due to more autumn snows?

AbruptSLR

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #719 on: June 21, 2017, 06:03:10 PM »
Latest MSL data from March 2017. Any thoughts/explanations on why MSL has been flat for over a year? Seems incredulous due to all the melting of Greenland and Antarctica? Could it be related to in the influx of colder water reducing the thermal expansion effects?

While I concur with the posts from wehappyfew, rboyd & oren; scale can also clarify what is happening.  The attached Jason-2 sea level time series thru May 2017 shows a trend line slope of 4.41 mm/yr; vs the trend line slope that you showed of 3.28 mm/yr.  This difference shows the contribution of meltwater, but you do not notice it in your post because you are distracted by ENSO induced fluctuations between varying rainfall patterns between land and ocean and also ENSO induced fluctuations between heat absorbed by the ocean (the ocean absorbs more heat energy during a La Nina and less heat during an El Nino).
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bbr2314

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #720 on: June 22, 2017, 07:49:09 AM »


Latest MSL data from March 2017. Any thoughts/explanations on why MSL has been flat for over a year? Seems incredulous due to all the melting of Greenland and Antarctica? Could it be related to in the influx of colder water reducing the thermal expansion effects?

This might have something to do with it.



Lennart van der Linde

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #721 on: June 27, 2017, 07:40:58 AM »
Chen et al 2017, The increasing rate of global mean sea-level rise during 1993–2014:
https://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate3325.html

Abstract
Global mean sea level (GMSL) has been rising at a faster rate during the satellite altimetry period (1993–2014) than previous decades, and is expected to accelerate further over the coming century. However, the accelerations observed over century and longer periods have not been clearly detected in altimeter data spanning the past two decades. Here we show that the rise, from the sum of all observed contributions to GMSL, increases from 2.2 ± 0.3 mm yr−1 in 1993 to 3.3 ± 0.3 mm yr−1 in 2014. This is in approximate agreement with observed increase in GMSL rise, 2.4 ± 0.2 mm yr−1 (1993) to 2.9 ± 0.3 mm yr−1 (2014), from satellite observations that have been adjusted for small systematic drift, particularly affecting the first decade of satellite observations. The mass contributions to GMSL increase from about 50% in 1993 to 70% in 2014 with the largest, and statistically significant, increase coming from the contribution from the Greenland ice sheet, which is less than 5% of the GMSL rate during 1993 but more than 25% during 2014. The suggested acceleration and improved closure of the sea-level budget highlights the importance and urgency of mitigating climate change and formulating coastal adaption plans to mitigate the impacts of ongoing sea-level rise.

Also see:
https://theconversation.com/contributions-to-sea-level-rise-have-increased-by-half-since-1993-largely-because-of-greenlands-ice-79175?utm_source=twitter&utm_medium=twitterbutton
« Last Edit: June 27, 2017, 08:01:47 AM by Lennart van der Linde »

AbruptSLR

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #722 on: June 27, 2017, 03:10:34 PM »
The mass contributions to GMSL increase from about 50% in 1993 to 70% in 2014 with the largest, and statistically significant, increase coming from the contribution from the Greenland ice sheet, which is less than 5% of the GMSL rate during 1993 but more than 25% during 2014.

Ice mass loss from WAIS has the potential to accelerate much faster than from the Greenland ice sheet.  We should find-out just how fast this acceleration will be in the next two to three decades.
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AbruptSLR

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #723 on: July 12, 2017, 10:09:43 PM »
Here is what Rotterdam is doing to prepare for coming sea level rise:

"The Dutch Have Solutions to Rising Seas. The World Is Watching."

https://www.nytimes.com/interactive/2017/06/15/world/europe/climate-change-rotterdam.html

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AbruptSLR

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #724 on: July 18, 2017, 12:14:44 AM »
The linked article indicates that a satellite snafu masked the true rate of increase of SLR:

Jeff Tollefson (17 July 2017), "Satellite snafu masked true sea-level rise for decades", Nature, 547, Pages: 265–266, doi:10.1038/nature.2017.22312

http://www.nature.com/news/satellite-snafu-masked-true-sea-level-rise-for-decades-1.22312

Extract: "Revised tallies confirm that the rate of sea-level rise is accelerating as the Earth warms and ice sheets thaw.

In an analysis published in Geophysical Research Letters in April, Cazenave’s team tallied up the various contributions to sea-level rise, including expansion resulting from warming ocean waters and from ice melt in places such as Greenland. Their results suggest that the satellite altimetry measurements were too high during the first six years that they were collected; after this point, scientists began using TOPEX/Poseidon's back-up sensor. The error in those early measurements distorted the long-term trend, masking a long-term increase in the rate of sea-level rise."
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AbruptSLR

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #725 on: July 18, 2017, 05:48:14 PM »
While the timeframe in the linked article may be too slow by a factor of about 2, it nevertheless, provides a nice summary of some of the key SLR risks that we are facing from the Antarctic Ice Sheet:

Title: "Antarctic Tipping Points for a Multi-Metre Sea Level Rise"

http://www.resilience.org/stories/2017-01-26/antarctic-tipping-points-for-a-multi-metre-sea-level-rise/

Extract:
•   "The Amundsen Sea sector of the West Antarctic Ice Sheet has most likely been destabilized and ice retreat is unstoppable for the current conditions.
•   No further acceleration in climate change is necessary to trigger the collapse of the rest of the West Antarctic Ice Sheet on decadal time scales.
•   Antarctica has the potential to contribute more than a metre of sea-level rise by 2100.
•   A large fraction of West Antarctic basin ice could be gone within two centuries, causing a 3–5 metre sea level rise.
•   Mechanisms similar to those causing deglaciation in West Antarctica are now also found in East Antarctica.
•   Partial deglaciation of the East Antarctic ice sheet is likely for the current level of atmospheric carbon dioxide, contributing to 10 metres of more of sea level rise in the longer run, and 5 metres in the first 200 years."
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Shared Humanity

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #726 on: July 19, 2017, 04:30:50 PM »
The linked article indicates that a satellite snafu masked the true rate of increase of SLR:

Jeff Tollefson (17 July 2017), "Satellite snafu masked true sea-level rise for decades", Nature, 547, Pages: 265–266, doi:10.1038/nature.2017.22312

http://www.nature.com/news/satellite-snafu-masked-true-sea-level-rise-for-decades-1.22312

Extract: "Revised tallies confirm that the rate of sea-level rise is accelerating as the Earth warms and ice sheets thaw.

In an analysis published in Geophysical Research Letters in April, Cazenave’s team tallied up the various contributions to sea-level rise, including expansion resulting from warming ocean waters and from ice melt in places such as Greenland. Their results suggest that the satellite altimetry measurements were too high during the first six years that they were collected; after this point, scientists began using TOPEX/Poseidon's back-up sensor. The error in those early measurements distorted the long-term trend, masking a long-term increase in the rate of sea-level rise."


"Nerem's team calculated that the rate of sea-level rise increased from around 1.8 millimetres per year in 1993 to roughly 3.9 millimetres per year today as a result of global warming."

This rate of increase can be seen as a 2 mm increase in the rate of sea-level rise in the past 2 decades or it can be seen as a doubling in the rate of sea level rise in the past 2 decades. How it is viewed can have dramatic implications on the anticipated increase in sea level by the end of the century.

"If sea-level rise continues to accelerate at the current rate, Nerem says, the world’s oceans could rise by about 75 centimetres over the next century. That is in line with projections made by the Intergovernmental Panel on Climate Change in 2013."

And this projection of 75 centimeters by 2100 indicates that the research team believes that the rate of increase is linear, essentially rising by 2 millimeters every 2 decades. I did a back of the envelope calculation (literally back of the envelope calculation with a pencil) and, using a 2 millimeter rate of increase over 2 decades  and starting at 4 millimeter rate in 2020, sea levels will rise an additional 64 centimeters by 2100.

Perhaps the research team is right and the rate of increase is linear. I don't have the annual measures to evaluate but, instinctively, I am troubled by this assumption of a linear rate of increase. All across the planet, we are watching individual processes accelerate at an exponential rate (glacier speeds and melt, ice sheet melt, atmospheric warming, methane increases etc.). It seems counter intuitive to think that sea level rise which, in a sense, is capturing the impact of all of these accelerating trends would result in a linear increase in the rate of sea level rise.

If we, instead, interpret this essentially 2 millimeter increase over 2 decades as a doubling of the rate of increase and project this doubling of the rate of increase to persist, my back of the envelope calculation suggests an additional 178 centimeters of sea level rise by 2100. IMHO, this is a far better projection.

(Feel free to perform your own calculations. I am an old man with declining faculties, using a dirty envelope and a blunt pencil.)
« Last Edit: July 19, 2017, 04:57:20 PM by Shared Humanity »

rboyd

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #727 on: July 20, 2017, 06:51:29 AM »
If we, instead, interpret this essentially 2 millimeter increase over 2 decades as a doubling of the rate of increase and project this doubling of the rate of increase to persist, my back of the envelope calculation suggests an additional 178 centimeters of sea level rise by 2100. IMHO, this is a far better projection.

(Feel free to perform your own calculations. I am an old man with declining faculties, using a dirty envelope and a blunt pencil.)

The end result is very dependent upon the doubling time, if its closer to a doubling each decade (as could be the case as the WAIS and Greenland accelerate as proposed by Hansen) then the multiples of 178.

Coffee Drinker

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #728 on: July 21, 2017, 08:03:23 AM »
So many coastal areas will be flooded and still people buy seafront property like there is no tomorrow. At least insurance companies become aware of this and already increase their flood risk premiums.

Me and my wife just withdrew an offer for our new house as it is in a 5% (5% flood risk per year) zone. Better safe than sorry. The real estate agent was a bit surprised when I explained her our concerns with global warming and sea level rise. Oh well.

My personal fear is not so much the immediate flooding but the loss of value in the future and problem to sell it again. In 10 years it may be in the 20% flood zone and in 30 years it may get flooded each year.

I know this is not really scientific contribution but global warming has already real consequences and affects our decisions. And I think when people feel the consequences at their own property or finances they will finally wake up. So far global warming is too abstract for most normal folks to really care.
« Last Edit: July 21, 2017, 08:12:59 AM by Coffee Drinker »

Lennart van der Linde

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #729 on: July 26, 2017, 09:35:12 AM »
Tamino on accelerating SLR, according to tide gauge and satellite data:
https://tamino.wordpress.com/2017/07/25/sea-level-rise-has-accelerated/

"How fast, you may ask, is the estimated trend since 1993 according to these tide-gauge-based data? It’s 3.56 mm/yr, even larger than the estimated rate from satellite data... Do bear in mind that the difference (from the satellite-based estimate) isn’t statistically significant. Essentially, they agree (certainly within their uncertainty limits)."

AbruptSLR

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #730 on: August 14, 2017, 04:21:48 PM »
Many people think that SLR is a concern of the future, but 25 million people around the world have already been displaced due to SLR and should the WAIS reach a tipping point circa 2040-2060 ASLR could make matters (including climate refugees, see the linked article) a lot worse than currently projected:

Title: "Refugees of a different kind are being displaced by rising seas — and governments aren't ready"

https://www.cnbc.com/2017/08/11/climate-change-refugees-grapple-with-effects-of-rising-seas.html

Extract: "Increasingly, the phenomenon of rising sea levels has amplified fears over climate refugees — individuals forced to leave their homes due to changing environmental conditions in their respective homelands. Climate watchers estimate that at least 26 million people around the world have already been displaced, and that figure could balloon to 150 million by 2050, according to the Worldwatch Institute."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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rboyd

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #731 on: August 14, 2017, 08:21:30 PM »
In the richer nations the issue is that we treat property as a financial asset, against which we borrow huge amounts of money. The vast majority of bank lending is against property. Once perceptions change, and they tend to 'tip' surprisingly fast, that collateral will lose most of its value and large chunks of the banking systems in many countries will be insolvent.

Once perceptions of 1 to 3 feet within 30-50 years get into people's minds large chunks of many cities will fall heavily in price. Many decades before the actual waters engulf the properties. Add the odd hurricane hitting a major city and it could turn into a financial stampede for the exits.

Sigmetnow

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #732 on: August 15, 2017, 08:45:45 PM »
"The Trump administration is acting very rashly in part out of the desire to undo a climate measure under the Obama administration," he said. "This is an enormous mistake that is disastrous for taxpayers. The (Obama) rule would have saved billions of dollars over time."

Trump to revoke Obama-era flood risk building standards
U.S. President Donald Trump will revoke an Obama-era executive order on Tuesday that required strict building standards for government-funded projects to reduce exposure to increased flooding from sea level rise, sources said. ...
http://mobile.reuters.com/article/amp/idUSKCN1AV1ZI
People who say it cannot be done should not interrupt those who are doing it.

AbruptSLR

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #733 on: August 18, 2017, 11:49:13 PM »
Scribbler discusses present (and near present) SLR risks due to contributions from Antarctica and Greenland over the coming 1 to multiple decades.  While generally presenting a reasonable picture, this article ESLD with regards to at least:

- Scribbler cites NOAA's 2016 490 ppm CO₂-eq value without correcting for the GWP100 of methane; which had he done so would give a value of 521 ppm.

- Scribbler does not discuss the bi-polar seesaw mechanism that can accelerate marine glacial ice mass loss (particularly in the WAIS) on a decadal timeframe but which is poorly represented in the CMIP5 projections.

- Scribbler does not cite the recent research that indicates that since 1750 global warming has sequestered substantial amount of heat content in the Southern Ocean at a water depth conducive for accelerating ice mass loss from marine glaciers (particularly in West Antarctica).

- Scribbler does not cite that beginning in the 1970's the ozone hole over Antarctica accelerated the circumpolar winds to a near optimal velocities for advecting CDW towards the grounding lines of associated marine glaciers and that as the ozone hole has begun to heal itself, the concurrent increase in GHG concentrations has kept the circumpolar wind velocities within the optimal range for such advection:

The Present Threat to Coastal Cities From Antarctic and Greenland Melt

https://robertscribbler.com/2017/08/18/the-present-threat-to-coastal-cities-from-antarctic-and-greenland-melt/

Extract: "With global temperatures now exceeding 1 C and with these temperatures likely to exceed 1.5 C within the next two decades, it is certain that broader heat-based stresses to these various glacial systems will increase. And we are likely to see coincident melt rate acceleration as more glaciers become less stable. The result is that coastal flooding conditions will tend to follow a worsening trend — with the most vulnerable regions like the U.S. Gulf and East Coasts feeling the impact first. Unfortunately, there is risk that this trend will include the sudden acceleration of various glaciers into the ocean, which will coincide with rapid increases in global rates of sea level rise. In other words, the trend for sea level rise is less likely to be smooth and more likely to include a number of melt pulse spikes.

Such an overall trend including outlier risks paints a relatively rough picture for coastal city planners in the 1-3 decade timeframe. But on the multi-decade horizon there is a rising risk that sudden glacial destabilization — first in Greenland and West Antarctica and later in East Antarctica will put an increasing number of coastal cities permanently under water."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
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Sigmetnow

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #734 on: August 19, 2017, 08:13:21 PM »
Miami Taxpayers Asked to Foot the Bill to Protect the City from Climate Change
Miami is among the U.S. cities most vulnerable to rising seas due to climate change, and city officials estimate that they may have to spend at least $900 million in the coming decades to upgrade the city’s flood prevention and drainage systems to keep the Atlantic Ocean at bay.

City officials don’t know exactly where all the money will come from, but in November the city will ask voters to approve a $400 million general obligation bond—new property taxes that will start chipping away at the cost of shoring up the city against the ravages of climate change. ...
https://www.climateliabilitynews.org/2017/08/16/miami-florida-climate-change-sea-level-rise-adaptation/
People who say it cannot be done should not interrupt those who are doing it.

AbruptSLR

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #735 on: August 20, 2017, 01:16:40 AM »
The linked July 14, 2017 article entitle: "ADB warns climate change 'disastrous' for Asia"; indicates that a BAU approach to climate change would be disastrous for Asia (particularly w.r.t. SLR and storm surge, as indicated by the attached image showing the coastal population [in millions per country in the year 2000] subject inundation by 2100 following an ESLD IPCC BAU scenario):

https://phys.org/news/2017-07-asia-dire-future-toll-climate.html

Extract: "A business-as-usual approach to climate change will be "disastrous" for Asia, undoing much of the phenomenal economic growth that has helped it make vast inroads against poverty, the Asian Development Bank said in a report released Friday

While a 2 degrees Celsius rise will be difficult to manage, "one can assume that a 4 degrees Celsius increase would lead to humanitarian disasters in many nations and result in unmanageable migration flows or locked-in populations", the report said.

Asia as a whole would see sea levels rise by 1.4 metres (4.6 feet) within this century, nearly twice the projected increase under the Paris deal, and face more destructive cyclones, it said."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

AbruptSLR

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Re: Sea Level Rise and Social Cost of Carbon
« Reply #736 on: August 23, 2017, 05:53:15 PM »
SLR is not uniform around the planet and the linked reference provides updated insight on this 'fingerprint' effect based on GRACE gravity data:

Chia-Wei Hsu & Isabella Velicogna (22 August 2017), "Detection of Sea Level Fingerprints derived from GRACE gravity data." Geophysical Research Letters, DOI: 10.1002/2017GL074070

http://onlinelibrary.wiley.com/doi/10.1002/2017GL074070/abstract?utm_content=bufferda45e&utm_medium=social&utm_source=twitter.com&utm_campaign=buffer

Abstract: "Mass changes of ice sheets, glaciers, ice caps, land water hydrology, atmosphere, and ocean cause a non-uniform sea level rise due to the gravitational and self-attraction and loading effects, called sea level fingerprints (SLF). SLF have been previously derived from a combination of modeled and observed mass fluxes from the continents into the ocean. Here, we derive improved SLF from time series of time-variable gravity data from the GRACE mission for April 2002-October 2014. We evaluate the GRACE-derived SLF using Ocean Bottom Pressure (OBP) data from stations in the tropics, where OBP errors are the lowest. We detect the annual phase of the SLF in the OBP signal and separate it unambiguously from the barystatic sea level (BSL) at two stations. At the basin scale, the SLF explain a larger fraction of the variance in steric-corrected altimetry than the BSL, which has implications for evaluating mass transport between ocean basins."
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson