Stunning new sea level rise research, Part 1: “Most likely” 0.8 to 2.0 meters by 2100

Two major new studies, in Nature and Science, sharply increase the projected sea level rise (SLR) by 2100. This post discusses the Science study, “Kinematic Constraints on Glacier Contributions to 21st-Century Sea-Level Rise” (subs req’d), which concludes:

On the basis of calculations presented here, we suggest that an improved estimate of the range of SLR to 2100 including increased ice dynamics lies between 0.8 and 2.0 m.

… these values give a context and starting point for refinements in SLR forecasts on the basis of clearly defined assumptions and offer a more plausible range of estimates than those neglecting the dominant ice dynamics term.

Scientific analysis is finally catching up to scientific observation. In 2001, the IPCC projected that neither Greenland nor Antarctica would lose significant mass by 2100. The IPCC made the same basic projection again in 2007. Yet both ice sheets already are. As Penn State climatologist Richard Alley said in March 2006, the ice sheets appear to be shrinking “100 years ahead of schedule.”

So for over a year now, delayers like Bj¸rn Lomborg have been able to cling to (a misrepresentation of) the IPCC’s lowball SLR estimate (see “Debunking Bj¸rn Lomborg — Part II, Misrepresenting Sea Level Rise.Science‘s Richard Kerr explained what the IPCC did wrong and what the new study does right:

Warming glaciers raise sea level in two main ways. They add more water as they melt, and they also add water when ice breaks off from glacial flows. The incidence of this latter phenomenon has soared in recent years for some glaciers draining the southern Greenland Ice Sheet, much to the mystification of glaciologists. Unable to model such accelerated ice losses, members of the Intergovernmental Panel on Climate Change declined to include them in their widely cited projection of up to 60 centimeters of sea level rise by 2100.

Glaciologist W. Tad Pfeffer of the University of Colorado, Boulder, and his colleagues tackled glacier flow anyway. They calculated how fast glaciers would have to flow in order to raise sea level by a given number of meters and then considered whether those flow rates were plausible or even physically possible.

Needless to say, a sea level rise of one meter by 2100 would be an unmitigated catastrophe for the planet, even if sea levels didn’t keep rising several inches a decade for centuries, which they inevitably would. The first meter of SLR would flood 17% of Bangladesh, displacing tens of millions of people, and reducing its rice-farming land by 50 percent. Globally, it would create more than 100 million environmental refugees and inundate over 13,000 square miles of this country. Southern Louisiana and South Florida would inevitably be abandoned, especially in the face of a steadily increasing number of killer super-hurricanes (see “Nature: Hurricanes ARE getting fiercer — and it’s going to get much worse“).

These results should come as no surprise to anybody but deniers and delayers. The scientific literature has been moving in this direction for a couple of years now — too late for the IPCC to consider in its latest assessment. For instance, an important Science article from 2007 used empirical data from last century to project that sea levels could be up to 5 feet higher in 2100 and rising 6 inches a decade (see Inundated with Information on Sea Level Rise)! Another 2007 study from Nature Geoscience came to the same conclusion (see “Sea levels may rise 5 feet by 2100“). Leading experts in the field have a similar view (see “Amazing AP article on sea level rise“).

Since delayers like to hide behind the IPCC’s 2007 sea level estimate — even though they really don’t believe most of what the IPCC says or most of the scientific literature on which it bases its conclusion — you’re going to be hearing the IPCC estimate for another several years, until the IPCC does a new report and puts in a more realistic estimate. That said, while the delayers never acknowledge it, even the 2007 IPCC report “was the first to acknowledge that the melting of the Greenland ice sheet from rising temperature [which would raise the oceans 23 feet] could result in sea-level rise over centuries rather than millennia,” as the NYT put it (see “Absolute MUST Read IPCC Report: Debate over, further delay fatal, action not costly“).

Part 2 looks at new paleoclimate research on how fast Greenland could shed ice.

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21 Responses to Stunning new sea level rise research, Part 1: “Most likely” 0.8 to 2.0 meters by 2100

  1. John McCormick says:

    The Houston-Galveston ship channel is obviously at sea level and is the home of 42 percent of America’s petrochemical industry.

    Aside from losing that industry as the sea slowly rises, that land is possibly the most toxic in the US.

    John McCormick

  2. Peter Black says:

    For a detailed view of what’s at stake in the US with rising sea levels, take a look at this interactive map I made using the EPA’s own data…data they are very careful not to publicize too much lest it give credence to the concept of actually doing something about AGW:

    Go ahead. check out south florida, the bay area, maine, new york city, North Carolina…

    We can’t afford to sit on our hands any longer on this issue.

  3. Robert says:

    2 metres by 2100 still won’t be enough to frighten people into doing anything about it. Individuals accept that they will be dead by 2100 and that sounds a lot more scary than a small SLR.

    We live at the top of a hill. I’ve never been to Bangladesh and won’t miss Florida much either. Sorry if this soundfs insensitive but it is the way that 99% of people will view it.

  4. paulm says:

    This is how the BBC began its report on the new find…
    Sea levels globally are very unlikely to rise by more than 2m (7ft) this century, scientists conclude.

    Surprisingly, the opposite to here.

    It states that…

    …US team concludes that a rise of 2m would need glaciers to reach speeds that are “physically untenable”…

    However, I am sure I have come across articles that have indicated that there might have been meter level rises over periods around a decade in the past. So this statement is misleading.

    SLR combined with increased precipitation is going to affect the coast line even more than expected. Look at the flooding now happening in Haiti on its north coast.

    With higher sea levels and increased extreme precipitation, coast lines will retreat even more than currently predicted.

    [JR: Yeah, I saw someone else misframe this. I’ll blog on this next week. It just goes to show how little the media understands how brutally devastating even one meter would be.]

  5. paulm says:

    Surprisingly, the opposite to here.

    should read

    Surprisingly, the opposite emphasis to here.

  6. Bob Wallace says:

    Robert, again I think you wrong.

    Most people care about their families. Often more than they care about themselves. Lots of people are concerned about the future they are leaving for their grandchildren.

    Additionally people care about their real estate values. As it becomes obvious that lots of coastal properties are going to become worthless in a few decades property values will start to decline.

    Even further, there are a lot of people who are going to get concerned about where all those “people that don’t look like me” from Bangladesh are going to move.

    At that point probably even you will start to get less insensitive.

  7. Peter Black says:

    robert, more that half the US population lives within 50 miles of the coast. Most people love the beach. A SLR of 2 meters would utterly destroy massive parts of our infrastructure as well as the economy of any seaport and coastal area. It would be a catastrophe.

    I sincerely hope we are not so shortsighted as to leave this to our grandchildren.

  8. Political Will, Political Won’t

    The accepted wisdom of today’s environmental reform movement is founded on two core assumptions. The first is that most of the technical solutions we need to address the world’s various crises are available, or at least could be swiftly developed by sufficiently intelligent, hard-working people. The second assumption is that all that’s lacking for a successful outcome is the political will to put these technical solutions into effect.

    Whether the discussion turns to replacing coal-fired power plants with wind turbines and using electric cars instead of gas-driven SUVs, converting industrial agricultural practices to organic permaculture, or reversing the decline of ocean life though international regulations, it is an article of faith in the reform movement that we know what we need to do and all that’s lacking is a sufficiently visionary leader to put more planet-friendly solutions in place.

    Both those assumptions ignore significant aspects of the situation – aspects that must be addressed for the envisioned reforms to be successful. This article examines those two assumptions with an eye to uncovering the confounding issues.

    The array of problems
    As the following laundry list of negative trends clearly illustrates, the scale and diversity of the problems we face are significant.

    The amount of carbon dioxide in the atmosphere is approaching 400 parts per million.
    We are emitting carbon dioxide 10 times faster than one of the world’s largest known volcanic eruptions (the Deccan Traps) that was implicated in the Cretaceous-Tertiary extinction event 65 million years ago.
    Ice caps and glaciers are disintegrating.
    World oil production is on a 4 year plateau despite prices that have quadrupled during that time.
    In our oceans the coral reefs are dying, dead zones are expanding, and predatory fish species (the ones we eat) have declined by 90% in the last 50 years.
    The biomass of prey fish in the Great Lakes has fallen by 92% since 2000.
    The estimated extinction rate for plants and animals is at least 75 species per day.
    The Great Pacific Garbage Dump is full of plastic.
    Over 75,000 square miles of arable land is lost each year to urbanization and desertification.
    A billion people in over 110 countries are seriously affected by desertification.
    Nearly a third of the world’s cropland has been abandoned since WW II because of damage by intensive agriculture and erosion.
    On the American Great Plains, half the topsoil has been lost in the last hundred years.
    The Ogallala aquifer in the western United States is being drained up to 100 times faster than it is being refilled.
    Indian farmers have drilled over 21 million water wells using oil-well technology. They take 200 billion cubic tonnes of water out of the earth each year for irrigation.
    We have eaten more grain than we have grown in 7 of the last 8 years.
    World carry-over grain stocks were 130 days of consumption in 1986 – today, it’s only 53 days.
    The global per capita grain supply has fallen from 340 kg in 1984 to 300 kg today.
    The world price of fertilizer is rising exponentially.
    The IPCC predicts that climate change will cut African food production in half by 2020.
    The cost of food is skyrocketing world-wide. Some countries have responded by banning exports of wheat or rice.
    We are in the beginning stages of a global financial crisis that could result in either a deflationary or hyper-inflationary depression lasting for a decade or more.
    These sorts of problems are known as wicked problems. That means they are messy, circular, aggressive and interlinked, so that trying to solve one may worsen others. Each problem shows a trend, and all the trends appear to be worsening inexorably. In some cases the trends have been visible for centuries (for example the loss of arable land and desertification), sometimes for decades (as with the loss of aquatic biomass), and some like Peak Oil for a scant few years. In all cases the global trends show no signs of reversing, however much effort has been expended to alter their local or regional trajectories . As their effects become more pronounced, it becomes easier to see their potential to hit our globalized industrial civilization like a planet-sized version of Hurricane Katrina.

    As daunting as the individual problems are, the key to understanding the importance of this list is recognizing the degree of the linkages between them. In many cases, trying to solve one problem can inadvertently make others worse. One prominent example is the attempt to address global warming through the use of ethanol as a vehicle fuel. While there may have been some merit to that primary intention, the secondary effects – increasing dead zones in the oceans due to fertilizer runoff, and rising food prices due to the use of food crops as fuel – eliminated the overall benefit of the effort, and even created a net negative outcome.

    Similar knock-on effects have occurred in in other areas. The attempt to raise food production through irrigation and the use of petroleum-based fertilizers has depleted water tables and reinforced a style of agriculture based on a finite resource. The attempt to increase global living standards (and thereby reduce population growth) by exporting production facilities to regions with lower wage and environmental standards has backfired by increasing levels of water, air and soil pollution – increases that have been felt well beyond the boundaries of those regions. One dark quip that addresses this sort of backfire is, “Around every silver lining there is a cloud.”

    When viewed from this perspective it becomes obvious that dealing with the panoply of problems besetting our world involves considerably more than just knocking them down one at a time. If we don’t apply holistic, system-level thinking to the converging crisis, our well-meaning efforts stand an excellent chance of making the overall situation worse.

    I have concluded that it is a mistake to think of “solving” these problems in any global or final sense. Some of them may be improved regionally, especially if they are not in local conflict with other competing problems. The logical corollary is that there will be other regions where those same problems cannot be solved, due different local circumstances.

    The big question, however, concerns those problems that are not contained, that do not respect national or regional boundaries. Global warming and the death of ocean biomes affect us all, and failures to address these problems in any region can make the situation worse for everyone. In these cases, it’s obvious that a collective global response is called for – a response that brings together the political, economic, industrial and opinion-making institutions of our world. If these institutions acted together they might have a chance of implementing the deep and wide-ranging changes the situation calls for.

    Unfortunately, until now we have seen precious little evidence of such a collective response. For example, we have repeatedly seen climate change conferences break down or issue watered-down statements that fail to address the scale of the accelerating crisis. While individuals, citizens’ groups and even some governments are obviously aware of the urgency, collective action repeatedly fails to gain the required global traction.

    This state of affairs is no accident. This is not because of some dark and sinister cabal or conspiracy to hold back change in the name of personal profit, though there probably are some instances of that. The real reasons are at once more banal and more worrisome than the Bilderberg watchers assume. In the next section I will examine the structural reasons for this sorry situation.

    Politics, the high art of civilization

    In order to understand the role that politics plays in our collective failure to address the predicament described above, we need to examine the nature of modern civilization.

    Now, when I use the term “modern civilization” I’m not just talking about the growth of industrialism over the last two hundred years. I’m not even talking about the growth of Western culture over the last two thousand years. What we usually think of as “modern civilization” is the development, refinement and culmination of cultural changes that began ten thousand years ago.

    In turn, in order to understand modern civilization, we need to look even farther back, at how humans lived before we became “modern and civilized” and what happened to push our species across that threshold.

    Human beings have been around in one form or another for two and a half million years, first as homo habilis, then as homo erectus, and finally as homo sapiens. For virtually all of those 2.5 million years, we lived in harmony with our environment. While it may not always have been a comfortable life (how could it have been, without color cable television or cars?), we were nonetheless perfectly adapted to our habitat. This statement is supported by two facts: over most of that period our presence caused little or no damage to the planetary biosphere; and during that time the human population was essentially stable, growing to only 5 million or so in two and a half million years, for a net addition of a scant two people per year.

    Recently there have been some remarkable discoveries about the quality of life in the times before modern civilization. We have always known that society back then consisted of hunter-gatherers, organized as tribes. The classical impression was that the lives of these savages were, in the words of Thomas Hobbes, “solitary, poor, nasty, brutish and short”. Recent investigations have shown that in fact hunter-gatherer societies enjoyed a remarkable quality of life characterized by low levels of effort, plenty of leisure time, good nutrition, low levels of disease, egalitarianism, very low levels of suicide, homicide and warfare, a high degree of personal autonomy and close-knit communities. In the words of Marshall Sahlins, hunter-gatherers were “the original affluent society.” In one of our more damaging semantic restatements we have defined “subsistence” living as bad and “sustainable” living as good – even though in the context of a hunter-gatherer society, they mean exactly the same thing.

    So here we have a species that was exquisitely adapted to its environment, living an affluent yet sustainable life, treading lightly on the earth, never outgrowing or overrunning its habitat, at least in terms of the species as a whole. We lived in this harmony with our world for two and a half million years, or 99.6% of the time we have been on the planet. Then suddenly, in the last ten thousand years – a mere 0.4% eye blink of time – our population increased over 1000 times, we decimated the earth’s stocks of non-renewable resources, we cut down over 90% of the planet’s forests, we fished her oceans to the edge of extinction, and we live in a near-constant state of conflict with each other. In this grievously short time we have brought about all the wicked problems listed above. Pardon my French, but what the hell happened?

    In a word, it was agriculture.

    About 10,000 years ago humanity developed organized, settled agriculture. Over the next couple of thousand years our predominant social model changed from hunter-gatherers to cultivators. We settled down (as one has to, to raise crops), and started to form larger social structures – villages, towns and cities. Nobody is precisely sure why we developed agriculture, when our previous ways of life had been perfectly satisfactory for millions of years. It may have been precipitated by climate changes, or growing populations in some areas, or it may have been just one of those things. There is no doubt that the threshold of radical human change is clearly demarcated by fields of grain.

    The shift to settled cultivation entrained a host of other changes. Our diet was dramatically impoverished. Levels of chronic disease and malnutrition increased. Levels of social violence escalated. However, the most significant change was the introduction of hierarchies that had not previously existed in our social systems.

    Why the development of agriculture resulted in the simultaneous appearance of social hierarchies is still a matter of debate. My opinion is that it happened because the risk to farming communities from crop failures was very high. If the crops failed, these communities contained too many people to survive on local foraging or hunting – both because population densities were so high and because the habitat destruction caused by farming had reduced the amount of local wild food. There was also no way to bring in food from some other unaffected region. Therefore the risk of crop failures had to be mitigated. This mitigation involved many activities. For example, local hunting kept larger crop-eating pests at bay, irrigation helped in times of drought, and shamanic intercession took care of storms and blights.

    Each of these activities of hunter, irrigation engineer and shaman was highly specialized in comparison to the more generic farming skills required for planting and harvesting. Such specialization conferred power on the holders of those skills. This was especially true in the case of shamans, whose power could not be entirely learned, but was said to emanate come from a mysterious connection with the supernatural. Their attempt to exercise control over nature gave the shamans the real ability to exercise control over other people however (”Obey me or the gods will frown on us, and the crop failure will be your fault!”), and the first systematic hierarchies were born.

    The other significant change introduced by organized agriculture was the psychological effect of reliable surpluses of food. While the previous two and a half million years of our existence had been shaped by sustainable subsistence, agriculture introduced the possibility of producing more food than we needed, letting us distribute the required amount to the members of the community and store the excess.

    Centralizing the production of food and managing its distribution reinforced the development of hierarchies. Since some of the food was needed by people who had no direct hand in producing it (such as weavers, shamans and granary guards), some means had to be found of giving them equitable access to it. This meant coming up with a way of defining relative values for different kinds of work, and establishing a medium of exchange. In one stroke the concepts of money and wages appeared, resulting in a further transfer of power to those who established the value of work and controlled the money supply (and indirectly the access to food).

    As important as that development was, there was yet another fundamental cultural change brought about by the simple existence of a food surplus. For the previous two and a half million years, human wants had been satisfied by the concept of “enough”. People worked until they had enough, then they stopped. Now there was almost always “more than enough”. The perception that there was more than enough food caused a radical change in how we looked at the world.

    Food surpluses and the development of a medium of exchange made trade for non-food goods possible. The continued trade of ongoing food surpluses enabled a continuous growth in the material comfort of peoples’ lives. It did not take long for people to become accustomed to this new state of affairs. As memories of the past faded over just a few generations, the new conditions of growing abundance were rapidly accepted as the “natural” order of things.

    Modern Civilization
    We now have the two critical preconditions for “modern civilization”. The first is the belief that a continuous growth in material prosperity is the natural order of the human universe. The second is the belief that a power hierarchy is essential for the smooth functioning of the system.

    As always happens with hierarchies, power flows uphill. Along with it go the perquisites of power, the most important being the right to higher levels of material abundance than those lower in the pecking order. In order to ensure that this comfortable situation is maintained, part of the accumulated social power is used to protect the situation. This is done by strongly defending the two fundamental preconditions: the idea that both material growth and the need for hierarchy are natural, essential and unquestionable. Indeed, the status quo is best served if the rest of the community sees this situation as simply part of the matrix of the universe, the only possible way life could work, and that any suggestions to the contrary are the result of either some nefarious agenda or outright insanity.

    Guardian Institutions
    Over the centuries an interlocking system of guardian institutions has grown up to protect and defend the two key ideas of growth and hierarchy.

    Our economic and financial institutions cooperate with business and industry to set the value of work and control the money supply (thereby controlling access to food). In this role it doesn’t make any difference whether an economy is capitalist, socialist or communist. The core belief it guards is always the same one.

    Our educational institutions teach successive generations how the system works, giving them the tools to integrate into it and manipulate it at the same time as training them to see this as the only possible way the world could work.
    Our communications media reinforce this message by enlisting people in the growth paradigm. They do this both though overt messages like advertising and covert messages embedded in the story lines of entertainment.
    Our religious institutions (as distinct from the religions they purport to enshrine) are primarily normative social structures. Many incorporate an overt message that one should be content with things as they are. There are often injunctions against questioning authority, as all authority is seen to devolve from the supernatural – just as it did for the shamans of the early agricultural era.
    Our legal institutions enforce the norms of hierarchy in ways too numerous to count. These range from the protection of privilege (one law for the rich, one for the poor) to the preferential defense of property rights over human rights.
    Our political institutions sit at the tip of the pyramid. Political institutions encode, enshrine and manage the application of social power. Politics is the institution that legitimizes all the others. Because of its unique ability to make laws and its access to the legalized violence that defends those laws, politics is the fullest expression of the power hierarchy of modern civilization.
    At the base of the hierarchy, supporting it all, are an ever-diminishing number of farmers who apply ever-increasing amounts of knowledge, technology and petroleum to ensure an ever-expanding supply of food. Because at the core it is their food that makes the whole edifice possible.

    So where does that put us in relation to the array of wicked problems we listed at the beginning? Simply put, every one of these problems is the result of unbridled growth. They are the logical results of the continual exercise of the first precondition of modern civilization, the drummer we have been marching to for ten thousand years since the invention of agriculture.

    Why politics is the problem, not the solution
    In light of this analysis it should be obvious why we are repeatedly failing to address any of these wicked problems. The only permanent “solution” to any of them is the secession of growth. That idea is anathema to our guardian institutions. And as the occupants of the pinnacle of power, our politicians have every reason to derail efforts in that direction, no matter how small.

    Politics, regardless of party or ideology, is part of the problem and can never be part of the solution. While it may be easier for the average person to live under the rule of a more humane parcel of rogues, at its heart politics is the primary guardian institution of modern civilization. The role of all politics is to ensure that power is managed, and power is always managed for the benefit of the holders of power. It doesn’t matter whether the power managers are Democrats, Republicans, Tories, Grits, Social Democrats, Communists or a military junta. They all fulfill the same role in service of the same beneficiaries.

    In order to fulfill that role they unite with the other guardian institutions – the economic, industrial, legal. religious, educational and communications organizations. Together these institutions create, maintain and guard a noetic milieu (a globalized intuitive, non-rational consciousness) in which any values that challenge the two fundamental preconditions to modern civilization are seen as incomprehensible, self-evidently absurd, dangerous or even insane. Since the primary value system these guardians protect is the paradigm of continuous material growth, the most dangerous of all radical ideas are any proposals to limit, halt or reverse that growth.

    The influences of our guardian institutions are firmly embedded in our global culture. They have such power and such general support at all levels of society that it is ultimately fruitless to try and remove them from power by either direct or indirect confrontation. The penalties for trying this are severe and ruthlessly applied.

    In light of this, is there any hope for a return to a sustainable, egalitarian, interconnected, considerate and just civilization? I strongly believe that there is, but getting there will be neither sure nor easy.

    The institutions that stand between us and such a future are trapped by their dependence on the very paradigm they are sworn to protect. They defend the belief that permanent material growth is natural, possible and inevitable. While they defend that belief with laws, guns and television, ultimately their power comes from people who accept that premise. If people stop believing that such growth is possible the institutions’ power declines, no matter how many defense mechanisms they engage. If growth falters, the people lose faith and the institutions crack and crumble.

    Look back at the list of problems that led off the article. Every single one of them is the result of our growth encountering limits. While we may be able to figure out ways to temporarily circumvent some of these limits, the pattern is now clear. The growth of modern civilization is slowing down, and is even showing evidence of coming to a halt. For a guardian institution that depends on growth for its very survival, this is like a diagnosis of terminal cancer.

    What that means is that these institutions will inevitably start losing their monolithic top-down power. This dis-integration will leave “cracks in the sidewalk of civilization”. And just as grass grows through cracks in real concrete, small communities and individuals will start to appear through the metaphorical concrete of our industrial civilization.

    No one can predict when, where or how the dis-integration will appear. It will take different forms in different places. The response of the guardians will probably be violently draconian in most cases. But there are places where communities have already formed in anticipation of such an opportunity. Like “Gaia’s antibodies” they will work to heal the wounds, widen the cracks, and let the sunshine and fresh air revitalize the hidden earth. As the seed stock of the next phase of civilization they will spread their values on the wind.

    The next cycle of human experience on this planet will be very different from any that has gone before. We will have fewer resources, but more knowledge. We will have to deal with toxic landscapes, a warming climate, shifting rainfall patterns and the emergence of new diseases. To balance that we will have better communications and longer memories than any civilization that has gone before us. We will not fall back into the stone age, but neither will we motor off happily into the sunset in our electric cars. There will be hardship and misery, but there will also be joy – the joy that comes from looking forward, from participating in our communities, from the love of those around us. Above all, there will be the future.

    I’m indebted to the writing of Daniel Quinn and John Zerzan, as well as to Riane Eisler for her book “The Chalice and the Blade”. I’d also like to acknowledge the philosophy of Anarcho-Primitivism for its critique of civilization (though perhaps not for its suggested solutions).

    September 3, 2008

    © Copyright 2008, Paul Chefurka

    This article may be reproduced in whole or in part for the purpose of research, education or other fair use, provided the nature and character of the work is maintained and credit is given to the author by the inclusion in the reproduction of his name and/or an electronic link to the article

  9. Bob Wallace says:

    Steven Earl –

    This is a blog forum, not a publishing house.

    Can you boil those pages down to a concise statement?

  10. paulm says:

    Steven Earl Salmony could you summarize your post….

  11. Richard C says:

    Steven Earl – verbal diarrhea?

    Peter – yeah, yeah, yeah, big deal. Now tell us the important stuff, what is going to happen to the UK?

  12. David B. Benson says:

    My summary: As we leave the comfort of the Holocene on our climate adventure into the unknown, we will leave agriculture behind; the surviving remnant will revert to being hunter-gathers, as God originally intended before the fall.

  13. Robert says:

    Steven – agree with most of your post but it would have been simpler and more courteous to post a link instead:

  14. Robert says:

    The arctic ice retreat is gathering pace again and now looks very likely to beat the 2007 record.

    I hope it does. At least that will give the media a chance to get climate change back in the news. In the UK the bad news about the economy has pushed environmental issues right off the agenda.

  15. David B. Benson says:

    And possibly the seas will rise much more than just 2 meters by 2100 CE:

    Well written, scary story about ice melt.

  16. Mauri Pelto says:

    As one of the glaciologists examining glacier flow in Greenland. We understood the concept, were not mystified in 1980’s and published papers as such documenting the physics behind the acceleration of marine terminating outlet glaciers. The problem has been quantifying this. The basics have been reviewed here.
    Summary, ice thins at termius, the terminus floats more, restraining pressure of bed and fjord walls is reduced, glacier speeds up, calves more, thins more, until the glacier reaches a new point where restraining forces balancing the calving forces a the glacier front. The Jakobshavns effect was coined by Terry Hughes at the U of Maine in the 1980’s who was the advisor to Pfeffer and myself. This process has been demonstrated to be the real deal for acceleration of the ice sheet not the increased melt rate.

  17. Peter Sinclair says:

    the Telegraph headline is
    “An Inconvenient Truth exaggerated sea level rise”

    [JR: Another piece of misinformation from the media.]

  18. Phil says:

    Stephen Earl: Please, please, please, get your own blog set up and post on there.

    Mauri: Thanks for that explanation. But it does beg the obvious question. To what extent will rising sea levels accelerate glacial flow? Seems like a nice little positive feedback loop there.

  19. shop says:

    Our political institutions sit at the tip of the pyramid. Political institutions encode, enshrine and manage the application of social power. Politics is the institution that legitimizes all the others. Because of its unique ability to make laws and its access to the legalized violence that defends those laws, politics is the fullest expression of the power hierarchy of modern civilization.

  20. JCH says:

    My question, why just by 2100? What happens by 2125, or 2150? It’s gives the public the impression this all wraps up in 2100 – home free for the planet.

    [JR: That’s just the canonical year. I think I’m clear that the rate in 2100 — perhaps 10 inches a decade (or more) — is equally important.]

  21. JCH says:

    Under BAU, Al Gore minimizes the threat of SLR.

    [JR: I have no idea what that means. Source?]