Re: The urgent necessity to halt Greenland meltdown
John Nissen
here it isLetter: Greenland meltdown and the reasons it matters
From John Nissen, Chair of the Planetary Restoration Action Group, London W5, UK🙏DougSent from my iPhone (audio texting)On Jan 24, 2026, at 5:41 PM, John Nissen <johnnis...@gmail.com> wrote:Dear John,Re 1. Greenland meltwater causing at least as much meltwater being discharged from AntarcticaThe effect of Greenland meltwater on Antarctic glaciers can be clarified. The sea level rise in Antarctica would cause grounding line retreat for some major glaciers, thereby accelerating glacier discharge [1] [2]. This acceleration would add to existing acceleration from other causes. A sea level rise of over half a metre can be expected from Antarctic glaciers this century; see 60 cm in [3]. With over half a metre from Greenland further stimulating discharge from Antarctica, a total of well over one metre becomes likely this century.[Original queried text]The dynamics of the planet means that this meltwater would directly raise sea levels in Antarctica, causing glacier collapse and raising the sea level by well over a metre. Once started, further collapse would be impossible to stop.[Suggested replacement]Meltwater from Greenland would raise the sea level in Antarctica, causing some major glaciers to boost their discharge of ice. A number of glaciers are already in a critical condition, and their contribution to sea level rise could easily match that of Greenland, making a total of over a metre quite likely this century.[The whole paragraph]A prime reason for Trump’s interest in Greenland is to exploit its resources, as recognised by a Danish investment fund’s ‘huge appetite’ to invest in Greenland (FT, 18th Jan)”. However, treating Greenland as a resource prize while its ice sheet melts is reckless. Greenland’s ice sheet holds enough ice to raise the global sea level by over 7 metres; a partial collapse could release over half a metre this century. Meltwater from Greenland would raise the sea level in Antarctica, causing some major glaciers to boost their discharge of ice. A number of glaciers are already in a critical condition, and their contribution to sea level rise could easily match that of Greenland, making a total of over a metre quite likely this century.Kind regards, JohnP.S. For uniformity, the "11 billion USD per year" for SAI should be written in the same format as the "$700bn per year" estimated financial cost for one metre of sea level rise.[1] Santos et al. (AGU, 2021)Drivers of change of Thwaites Glacier, West Antarctica, between 1995 and 2015[2] Pine Island glacier[3] AntarcticGlaciers.orgSea level riseOn Fri, Jan 23, 2026 at 1:29 PM John Nissen <johnnis...@gmail.com> wrote:Dear John,Thanks for your interest. Trump's withdrawal from his invasion threat is good news. But the fact remains that the US, Russia and China are vying with one another for exploitation of the Arctic, attracted by reduced ice cover. This short-term thinking seems to be in complete disregard for the long-term catastrophic consequences of Arctic meltdown, one of which inevitably being metres of sea level rise without prompt SAI intervention.(The consequences of allowing the meltdown to continue are not just for sea level but for climate change: a further escalation in extreme weather events. Storm surges and river flooding will add to the problem of sea level rise for coastal communities. The situation is liable to get out of control without deployment of SAI within the next few years according to my trend analysis and engineering calculations - but I do not yet have a published paper on this. The good news is that prompt and appropriate deployment of SAI could actually reverse climate change and return the planet to a much safer state.)You raise three issues, the third of which certainly justifies a change of text, but I don't think the others do - I leave that to your judgement.1. Greenland meltwater causing at least as much meltwater being discharged from AntarcticaI specifically mention one mechanical mechanism, which is due to the way that West Antarctic glaciers are buttressed: they are typically retrograde, and buttressed at a grounding line. Thus raising the sea level accelerates the descent of these glaciers. Some are also buttressed by ice shelves which are separating from the terminations, partly due to the mechanical effect of sea level rise and partly due to warmer near surface water.I haven't managed to find specific papers to discuss these various effects, but I did google AI searches to confirm both the disproportionate sea level rise in Antarctica and the accelerating effect of raising sea level on Antarctic glaciers.(BTW, there is a second effect of Greenland meltwater on Antarctica which I could have mentioned but is rather complex. It is through the addition of cold freshwater to the surface of the North Atlantic part of the Atlantic Meridional Overturning Circulation (AMOC). This addition reduces the amount of brine produced when the surface water meets Arctic sea ice and melts it. The sinking brine is a main driver of the AMOC. The slowing of the AMOC has a heating effect on near surface water in the Antarctic which eats away at the glacier terminations, especially when the ice shelves have detached.)I can cite two examples of ominous precedence in the geological record. The Eemian had some thousands of years with a similar global temperature and sea level to our present ones. At the end of the period there was a collapse of Arctic and Antarctic ice sheets causing a sea level rise of 6-9 metres, with one third contribution from the Arctic and two thirds from the Antarctic, according to the climate guru, James Hansen. A second precedent was at the beginning of the Holocene, 11.7 thousand years ago, when the temperature measured from Greenland ice cores rose by 7-10 °C in around 50 years. The sea level rose 20 metres in 400 years, i.e. a metre every 20 years on average.2. Financial costThe estimate of $700bn per year came to me from John Moore who has carefully considered a paper by Brown et al; see [1]. If you look at Figure 4 and examine the cases where sea level reaches one metre or more, it is possible to establish an average cost value, summing the values for each different colour curve. John notes that the paper assumes sensible adaptation measures (such as sea dikes) are taken. He points out that many countries are averse to taking precautions as insurance against disasters, and those countries might suffer hundreds of times worse financial cost with a sudden sea level rise.The paper does not account for the cost of sea level rise in the matter of lives and livelihoods. The stresses from mass migration (or attempted mass migration) would likely lead to conflict. Overall there would be widespread economic collapse and a global security crisis, probably well in advance of the sea level reaching one metre.3. Arctic amplificationFour times was an approximation. A more precise estimate was given as 3.8 times in a paper here [2]. I suggest a change from "four" to "near four" for the letter.Kind regards, JohnP.S. I have asked Peter Wadhams whether he is happy to have his name included in the letter. This needs to be checked, if you decide to go ahead with publication.[1] Brown et al. (2021)Global costs of protecting against sea level rise at 1.5 to 4.0 °C[2] Rantanen et al. (Nature, 2022)The Arctic warmed four times faster than the globe since 1979On Thu, Jan 22, 2026 at 9:58 AM Letters Editor <letters...@ft.com> wrote:Dear Mr Nissen,Thanks for your interesting letter.I have highlighted some figures/stats in sections in bold. If you provide the sources for those.many thanksJohnDear editor,
A prime reason for Trump’s interest in Greenland is to exploit its resources, as recognised by a Danish investment fund’s ‘huge appetite’ to invest in Greenland (FT, 18th Jan)”. However, treating Greenland as a resource prize while its ice sheet melts is reckless. Greenland’s ice sheet holds enough ice to raise the global sea level by over 7 metres; a partial collapse could release over half a metre this century. [correct]
The dynamics of the planet means that this meltwater would directly raise sea levels in Antarctica, causing glacier collapse and raising the sea level by well over a metre. Once started, further collapse would be impossible to stop.
The financial implications are staggering: a single metre of sea level rise could cost the world $700bn per year according to one study. Even half a metre would devastate low-lying countries like Bangladesh and Vietnam, while several metres would obliterate coastal cities and agricultural areas globally. This is not a distant environmental concern, but a material threat to everyone on the planet: a threat currently ignored by nations competing for resources, sea routes and military advantage in the Arctic.
In 2012, I, alongside sea ice expert Peter Wadhams, testified to the UK Environmental Audit Committee regarding the urgency of protecting the Arctic. We warned that geoengineering was essential for Arctic preservation. Since then, Arctic temperatures have risen four times [think it's 3 to 4 times faster]faster than the global average, intensifying the risks from critical “tipping elements”, including the Greenland Ice Sheet.
A pressing need exists to start lowering the Arctic temperature while it is still just possible using the most powerful, available cooling technique: stratospheric aerosol injection (SAI). This technique mimics the cooling effect of large volcanic eruptions by injecting SO₂ into the stratosphere. Contrary to uninformed opposition, responsible research suggests that SAI could cool the Arctic with minimal risk of serious side effects, especially when compared to the risks from continued Arctic warming. The cost of such deployment has been estimated at around 11 billion USD per year.
While Trump remains determined to exploit Greenland rather than save it from meltdown, catastrophic sea level rise becomes inevitable.
Yours sincerely,
John Nissen
Chair of the Planetary Restoration Action Group, PRAG
8 Summerfield Road, Ealing, W5 1ND
On Tue, 20 Jan 2026 at 17:37, John Nissen <johnnis...@gmail.com> wrote:To: the editor of the Financial Times for publication
2026-01-20
The urgent necessity to halt Greenland meltdown
Dear editor,
A prime reason for Trump’s interest in Greenland is to exploit its resources, as recognised by a Danish investment fund’s ‘huge appetite’ to invest in Greenland (FT, 18th Jan)”. However, treating Greenland as a resource prize while its ice sheet melts is reckless. Greenland’s ice sheet holds enough ice to raise the global sea level by over 7 metres; a partial collapse could release over half a metre this century. The dynamics of the planet means that this meltwater would directly raise sea levels in Antarctica, causing glacier collapse and raising the sea level by well over a metre. Once started, further collapse would be impossible to stop.
The financial implications are staggering: a single metre of sea level rise could cost the world $700bn per year according to one study. Even half a metre would devastate low-lying countries like Bangladesh and Vietnam, while several metres would obliterate coastal cities and agricultural areas globally. This is not a distant environmental concern, but a material threat to everyone on the planet: a threat currently ignored by nations competing for resources, sea routes and military advantage in the Arctic.
In 2012, I, alongside sea ice expert Peter Wadhams, testified to the UK Environmental Audit Committee regarding the urgency of protecting the Arctic. We warned that geoengineering was essential for Arctic preservation. Since then, Arctic temperatures have risen four times faster than the global average, intensifying the risks from critical “tipping elements”, including the Greenland Ice Sheet.
A pressing need exists to start lowering the Arctic temperature while it is still just possible using the most powerful, available cooling technique: stratospheric aerosol injection (SAI). This technique mimics the cooling effect of large volcanic eruptions by injecting SO₂ into the stratosphere. Contrary to uninformed opposition, responsible research suggests that SAI could cool the Arctic with minimal risk of serious side effects, especially when compared to the risks from continued Arctic warming. The cost of such deployment has been estimated at around 11 billion USD per year.
While Trump remains determined to exploit Greenland rather than save it from meltdown, catastrophic sea level rise becomes inevitable.
Yours sincerely,
John Nissen
Chair of the Planetary Restoration Action Group, PRAG
8 Summerfield Road, Ealing, W5 1ND
Email: johnnis...@gmail.com
Phone: 07890 657 498
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rob...@rtulip.net
Hi John, congratulations on this excellent letter. Copying the text below as published in the Financial Times, shared by Doug Grandt (link is behind a paywall).
I see they introduced an error, replacing your text “SO₂ into the stratosphere” with “CO₂ into the stratosphere.” Hopefully that was not from you! Worth a correction.
When you consider the scale of infrastructure, agriculture and tourism at sea level, the annual $700 billion estimate looks low.
Coastal city flood losses > US$1 trillion per year by 2050 (no adaptation)
Hallegatte et al. model flood losses for 136 major coastal cities and note that without adaptation, aggregate losses by mid-century could rise to “more than US$1 trillion per year.”
By 2100, expected annual coastal flood losses of 0.3–9.3% of global GDP (without adaptation)
Hinkel et al. (PNAS) estimate, globally, that without adaptation a meaningful share of the world’s population could be flooded annually by 2100, with expected annual losses of 0.3–9.3% of global GDP (depending on scenario).
Order-of-magnitude protection costs for 1m SLR (older estimate)
The OECD’s Responding to Rising Seas cites Tol (2002) estimating global protection costs for 1 metre of sea-level rise at roughly 0.6–1.06 trillion (1995 USD) (not framed as “per year” in that cited passage).
Regards
Robert Tulip
Letter: Greenland meltdown and the reasons it matters
A prime reason for Donald Trump’s interest in Greenland is to exploit its resources, as recognised by a Danish investment fund’s “huge appetite” to invest in Greenland (“Denmark fund to beef up Greenland investments”, Report, January 19). https://www.ft.com/.../07f9879b-9f06-4b81-b41f-7822ed3797c4
However, treating Greenland as a resource prize while its ice sheet melts is reckless. Greenland’s ice sheet holds enough ice to raise the global sea level by over 7 metres; a partial collapse could release over half a metre this century.
The dynamics of the planet mean that this meltwater would directly raise sea levels in Antarctica, causing glacier collapse and raising the sea level by well over a metre. Once started, further collapse would be impossible to stop.
The financial implications are staggering: a single metre of sea level rise could cost the world $700bn per year according to one study. Even half a metre would devastate low-lying countries like Bangladesh and Vietnam, while several metres would obliterate coastal cities and agricultural areas globally.
This is not a distant environmental concern, but a material threat to everyone on the planet: a threat currently ignored by nations competing for resources, sea routes and military advantage in the Arctic.
In 2012, I, alongside sea ice expert Peter Wadhams testified to the UK parliament’s environmental audit committee regarding the urgency of protecting the Arctic. We warned that geoengineering was essential for Arctic preservation. Since then, Arctic temperatures have risen four times faster than the global average, intensifying the risks from critical “tipping elements”, including the Greenland Ice Sheet.
A pressing need exists to start lowering the Arctic temperature while it is still just possible using the most powerful, available cooling technique: stratospheric aerosol injection (SAI). This technique mimics the cooling effect of large volcanic eruptions by injecting CO₂ into the stratosphere. Contrary to uninformed opposition, responsible research suggests that SAI could cool the Arctic with minimal risk of serious side effects, especially when compared to the risks from continued Arctic warming. The cost of such deployment has been estimated at around $11bn per year.
While Trump remains determined to exploit Greenland rather than save it from meltdown, catastrophic sea level rise becomes inevitable.
John Nissen
Chair of the Planetary Restoration Action Group, London W5, UK
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Bruce Melton -- Austin, Texas
Here are several more references for extreme sea level rise effects:
Sea level rise adaptability limit...
The sea level rise adaptability limit, from the
IPCC Working Group II Report 2014, “Nicholls et al. (2011) show
that only a
limited number of adaptation options are available for specific
coastal areas
if sea level exceeds a certain threshold (1 m) at the end of the
century.”
Climate Change 2014: Impacts, Adaptation, and Vulnerability.
Part A: Global and
Sectoral Aspects. Contribution of Working Group II to the Fifth
Assessment Report of the Intergovernmental Panel on Climate
Change, page 393,
paragraph 10.
https://www.ipcc.ch/site/assets/uploads/2018/02/WGIIAR5-Chap5_FINAL.pdf
$27
Trillion Per year Damages from Sea Level Rise... If the 2 C
target is
missed, and we follow the RCP8.5_J14 scenario (median sea level
rise of 0.86m
and 95th percentile of 1.8m in 2100), global annual flood costs
without
additional adaptation are projected to be US$ 14.3 trillion per
year (2.5% of
GDP) for the median scenario and up to US$ 27.0 trillion per year
for the 95th
percentile (figure 4(a)), accounting for 4.7% of global GDP (table
S4).
Jevrejeva et al., Flood damage costs under the sea level rise with
warming of
1.5 and 2C, Environmental Research Letters, July 4, 2018.
http://iopscience.iop.org/article/10.1088/1748-9326/aacc76/pdf
Sea level rise costs of $14.2 trillion in
sea level rise
impacts by 2050 to 2080 (appropriately interpreted by shortly
after 2030)...
Kirezci
2020
(press release), "Coastal flooding across the world is set to
rise by
around 50 per cent due to climate change in the next 80 years,
endangering
millions more people and trillions of US dollars more of
coastal
infrastructure... The economic risk in terms of the
infrastructure exposed will
rise by up to $US14.2 trillion, which represents 20 percent of
global GDP..."
Kirezci uses RCP8.5 and 0.74 meters sea level rise, or 29 inches.
Note, the time of sea level rise has no bearing on when damages will occur. those damages willoccur whenever sea level rises as much as predicted. What does changes is the dollar amount of damages as the value of money changes over time.
Kirezci
et al., Projections of global-scale extreme sea levels and
resulting episodic
coastal flooding over the 21st Century, Nature, July 30, 2020.
https://www.nature.com/articles/s41598-020-67736-6.pdf
Press Release, University of East Anglia
http://www.uea.ac.uk/about/-/coastal-flooding-set-to-get-more-frequent-threatening-coastal-life-and-20-per-cent-of-global-gdp
Sweet et al., Global and Regional Sea Level Rise Scenarios for the United States, NOAA, January 2017.
https://tidesandcurrents.noaa.gov/publications/techrpt83_Global_and_Regional_SLR_Scenarios_for_the_US_final.pdf
Press
Release - NOAA, U.S.
high-tide flooding
continues to increase, July 14, 2020
https://www.noaa.gov/media-release/us-high-tide-flooding-continues-to-increase
New NOAA Technical Report on high tide flooding:
NOAA 2019 State of U.S. High Tide Flooding with a 2020
Outlook, TR 092, July
2020, page 3 and 4.
https://tidesandcurrents.noaa.gov/publications/Techrpt_092_2019_State_of_US_High_Tide_Flooding_with_a_2020_Outlook_30June2020.pdf
https://earth.gov/sealevel/us/internal_resources/756/noaa-nos-techrpt01-global-regional-SLR-scenarios-US.pdf
"There comes a threshold of sea level rise-induced flooding that makes normal routines impossible and drives hard choices." … "UCS defines flooding that occurs 25 times per year (on average, once every other week) or more as 'chronic inundation' [or] any coastal community that experiences this frequency of flooding over 10 percent or more of its land area, excluding wetlands and areas protected by federal levees."
(Union of Concerned Scientists (UCS), When Rising Seas Hit Home, 2017, quote box and par 5.)
https://www.ucsusa.org/resources/when-rising-seas-hit-home
"More than 300,000 of today's coastal homes, with a collective market value of about $117.5 billion today, are at risk of chronic inundation in 2045.” “By the end of the century, [or with 6.6 feet of sea level rise] … this includes as many as 2.4 million homes—the rough equivalent of all the homes in Los Angeles and Houston combined.”
(Union of Concerned Scientists (UCS), Underwater: Rising Seas, Chronic Floods, and the Implications for US Coastal Real Estate (2018), Report Summary, bullets 1 and 2)
https://www.ucs.org/resources/underwater
Dahl et al.,
Looming
Deadlines for Coastal Resilience: Rising Seas, Disruptive
Tides, and Risks to
Coastal Infrastructure, Union of Concerned Scientists, June
25, 2024.
https://www.ucsusa.org/sites/default/files/2024-06/Looming_Deadlines_for_Coastal_Resilience.pdf
Steep trails,
B
Director, Climate Change Now Initiative, 501c3
President, Melton Engineering Services Austin
8103 Kirkham Drive
Austin, Texas 78736
(512)799-7998
ClimateDiscovery.org
ClimateChangePhoto.org
MeltonEngineering.com
Face...@Bruce.Melton.395
Inst...@Bruce.C.Melton
The Band Climate Change
Twitter - BruceCMelton1
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John Nissen
John Nissen
H simmens
Herb Simmens
Author of A Climate Vocabulary of the Future
“A wonderful achievement, a SciencePoem, an Inspiration, a Prophecy, also hilarious, Dive in and see"
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@herbsimmens
On Feb 7, 2026, at 4:55 PM, John Nissen <johnnis...@gmail.com> wrote:
Michael MacCracken
Dear John--On sea level (SL) rise, I just don't see how adaptation has any chance of working over the long term.
Regarding sea level rise and a rough estimate of the magnitude of the effects on coastlines I have a tea mug that shows a map of the world for present sea level when not heated. Then when I heat it up for tea, the map on the mug shows what the coastlines would be with significant global warming. I don't recall what the projected increase in temperature and SL are for the heated case, but likely something like 3 C and perhaps 20 m of SL rise.
As you will see, the changes are very dramatic. For North America, Florida disappears and Hudson Bay grows, among other changes. For Asia, there are very large changes for Southeast Asia and China. And then for Europe, there is a huge change in the area of the Baltic nations, where my wife and I took a cruise this past fall and I noticed how low many of the coastlines are.
The notion that levees (or bigger barriers) will be able to be constructed to deal with the eventual rise seems very implausible to me. Searching the Web, I did find there was a proposal for dams to enclose the Baltic and North Sea--very challenging notion, and if one does a water balance for the enclosed area, there is more precipitation than evaporation, so it would also take pumps to keep the level down.
Pretty clearly, it seems to me that climate intervention to shave off and bring down warming is much more plausible than otherwise trying to protect the coastlines.
Best, Mike MacCracken
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Alan Kerstein
Hi Mike,
I would like to suggest an alternative to measures intended to stem coastal (possibly extending far inland) flooding that seems obvious although I haven’t seen it discussed, namely relocation.
Relocation is costly as well as heartrending if done suddenly at short notice. Implemented over decades guided by long-term planning, the effects on people and commerce can be substantially mitigated.
I will comment first on the built environment and then on land and people. All elements of the built environment - residential, commercial/industrial, and associated infrastructure - are subject to depreciation. Ongoing maintenance costs and routine modifications and upgrades can typically add up to the original construction costs over the course of a few decades. From this viewpoint, knowledge of possible regional effects of sea-level rise some decades hence can guide relocation decisions incurring costs far lower than the present economic value of the existing built environment.
Insurance of structures is already rising in cost largely in anticipation of increasingly severe environmental harms. In this regard, the deficit of long-term perspective on the part of individuals and businesses is partly overcome by insurance costs that transform long-term prospects into short-term incentives. Market mechanisms thus lend a helping hand.
Regarding flooded land, I refer to parents of newlyweds who say that they didn’t lose a son, they gained a daughter. Shallow continental shelves are not devoid of economic value. The North Sea is yielding an economic bonanza owing to its suitability for offshore wind. I can’t speak knowledgeably about the possible benefits of fisheries and other ecosystems in shallow waters.
Regarding the displacement of people, over a period of decades families are subject to geographical separation mainly by welcome developments such as children leaving home for education, employment, or to start their own families. Empty nesters inevitably vacate their abodes owing to death or infirmity. Such generational churn often hollows out communities for reasons other than climate change. These are unfortunate occurrences that can be exacerbated by warming-induced flooding, but fall well short of the notional impact of sudden swarms of climate refugees.
Whether the relocation is sudden or gradual, a lot of people will need to find someplace to go. The aforementioned hollowing out affects many regions that will not be subject to flooding and might benefit from inward migration. More broadly, the globally declining birth rate might align with the loss of land surface so as to mitigate the impact of reduced land surface.
This is doubly ironic. First, many people lament their inability to contribute materially to climate-change mitigation while they might be doing exactly that by limiting the sizes of their families. Second, falling birthrates mechanically reduce the global carbon footprint aside from putative reductions of the carbon footprint per person, yet the falling birth rate seems to be universally viewed as a serious problem requiring urgent attention although (fortunately in my view) it appears to be impervious to all attempted and proposed remedies (in this regard, unfortunately, much like climate change).
I certainly don’t downplay the seriousness of sea-level rise, but in view of well justified skepticism regarding the feasibility of protecting the coastlines, my point is to illustrate the feasibility of substantial harm reduction by means of long-term planning and coordination focused on relocation.
Alan
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Michael MacCracken
Dear Alan--The issue of moving back from the coast was considered during the first national climate change assessment in the late 1990s and I'm sure since then--and EPA studies were looking at issue through most of 1980s. Indeed, there have been communities looking at it and some cities I believe have plans for moving back, etc. Areas one wants to defend one tends to build roads on levees parallel to the coast; areas where one will be moving back roads are perpendicular to coast so one can move back. Studies have been done of indigenous villages in Alaska that will have to move and relocate and the complications of finding new sites, and in Louisiana a tribe has been relocating, etc.
There are then also areas/states that have banned thinking about it, even as they are paving roads thicker and thicker so they flood less often. I has been an issue in lots of places, and is complicated. Some locations have decided not to place key facilities (like hospitals) on low lying land while not banning vacation homes and other lower value properties.
There are just lots of complications. Way back in the 1970s when we at Livermore made our first color graphic of the topography of California, much of the Sacramento-San Joaquin delta showed up as blue, so below sea level. Not what you see on a map as much of the area in that region is islands with levees and the mostly farmland is below sea level; much land around the Bay Area is low lying--does one put a dam across the Golden Gate--lots to consider. For New York/Hudson River harbor there are proposals for dams (or at least storm surge barriers). Chesapeake Bay, the largest estuary on the East Coast is also very vulnerable--also because the land is also still subsiding since pushed up during the Last Glacial.
Just saying, the issue is here now with just a little bit of rise--with IPCC until recently only focusing on rise to 2100 (and generally understating risk of much larger increases that will become more likely as time goes on). If one goes back to deglaciation after Last Glacial Maximum, sea level rose 120 meters with about a 6 C increase in global average temperature that caused loss of about 2/3 of all ice on land. What I would say is generally lacking is local and regional thinking about being prepared for how high sea level could rise (based on paleo lessons) with a sustained 2-3 C warming--just too hard to be imaging.
Best, Mike
David,
Land per se is not relocatable, so it is not within the scope of my remarks about relocation. The choices then are to protect it or abandon it. This case-by-case policy choice is not entirely straightforward because agricultural productivity depends not only on soil quality but also on the seasonal cycle of temperature, precipitation, cloud cover, and humidity as well as local ecology, all of which are potentially affected by global warming. Also, in the future agricultural productivity will be weighed against carbon footprint and technological developments such as factory farming partly intended to address that concern.
Alan
On Sun, Feb 8, 2026 at 8:15 AM David Price <da...@pricenet.ca> wrote:
Hi Folks
A very short comment in response to Alan:
SLR impacts are not just about human habitation and infrastructure: Much of the world’s most productive agricultural land is in coastal regions — typically only a few metres above high tide SL, and in some regions even below present-day SL, where seawall defences have already been constructed.
DavidFrom my cellphone
I acknowledge that I reside on unceded Traditional Territory of the Secwépemc People
On Feb 7, 2026, at 7:14 pm, Alan Kerstein <alan.k...@gmail.com> wrote:
David Price
On Feb 7, 2026, at 7:14 pm, Alan Kerstein <alan.k...@gmail.com> wrote:
Hi Mike,
Alan Kerstein
David,
Land per se is not relocatable, so it is not within the scope of my remarks about relocation. The choices then are to protect it or abandon it. This case-by-case policy choice is not entirely straightforward because agricultural productivity depends not only on soil quality but also on the seasonal cycle of temperature, precipitation, cloud cover, and humidity as well as local ecology, all of which are potentially affected by global warming. Also, in the future agricultural productivity will be weighed against carbon footprint and technological developments such as factory farming partly intended to address that concern.
Alan
David Price
On Feb 8, 2026, at 10:15 am, Alan Kerstein <alan.k...@gmail.com> wrote:
Alan Kerstein
Thank you David and Mike -
To be clear, I’m just trying to present a laundry list of possible considerations and options in order to define the scope of the issue, and your responses are helpfully putting flesh on the bones of my outline. To some extent I’m channeling Jonathan Swift’s proposal of eating babies to address the problem of famine, which intentionally elicited a reaction of revulsion much like the natural reaction to fully confronting the consequences of sea-level rise. Indeed, the fact that some of those consequences are just too hard to be imagining, as you say Mike, is a good reason to document those consequences in granular detail with reference to specific localities and to publicize them in local media. Personalizing climate harms in a relatable way might have the shock effect needed to get people to assess the options realistically, or as expressed in another context, “one death is a tragedy, a million is a statistic.” In particular, it might beneficially affect people’s perspective on SRM and on the triad more broadly.
Alan