This is Wayne Kernochan's Typepad Profile.
Join Typepad and start following Wayne Kernochan's activity
Join Now!
Already a member? Sign In
Wayne Kernochan
Recent Activity
I'll weigh in only to add some facts or guesses at facts not discussed last time. The reason afaik that different folks tend to come up with a different "multiple of CO2" value for methane is that when methane is at low levels it has a half-life of about 10 years, while when it is far greater it has a much longer half-life. The reason iirc is that when you have too much methane in the atmosphere, there's not enough oxygen to split off the hydrogen atoms as water (H2O) plus CO2. So a steady level of methane at today's levels may be equivalent to 20 times the effect of an equivalent amount of CO2, while 10 times today's amount might double methane's half-life in the atmosphere and have around 80 times the effect of the equivalent amount of CO2 (these are vague recollections of the CO2 equivalents given at the time, not exact figures). The question is, how much methane does it take to extend its half-life. Scientists at the time usually tended to believe we were nowhere near the threshold (I hate the term "tipping point"). Moreover, James Hansen et al in a draft paper a couple of years ago found that in the last two episodes of global warming (55 and 155 years ago) methane had a minimal effect. Instead, what supplemented CO2's direct effect were things like black carbon. Now, there are two things these analyses can't speak to. First, nobody knows just how much of permafrost melt will be released as methane, and how much as CO2. The former is worse in the short term, while the latter is actually worse in the long term (under certain assumptions). Second, no one really knows how our incredible acceleration of global warming will affect such things as what Neven cited, methane clathrates on the Arctic Ocean seafloor. A study someone cited at the time said flatly that methane clathrates there might melt, but the methane would be released as bubbles (i.e., go directly to the atmosphere) only at a depth of 10-60 feet, and those bubbles would be small (less than 10 meters in diameter. I am skeptical of this conclusion, as the Russian woman scientist who has been reporting Russian sampling over the last few years announced at one that they were seeing bubbles of more than 100 m in diameter in an area that seemed to be more than 100 meters in depth. My net so far is that methane appears right now to have too many hoops to jump through in order to do more than double, and therefore worrying about methane is probably less important than worrying about carbon emissions, from fossil fuels and the permafrost. But I do hope Neven finds out something new. I still do worry about it.
Toggle Commented 7 days ago on Beaufort quick update at Arctic Sea Ice
I can speak to the first question, although I can't remember if I read it in Hansen's Storms of My Grandchildren or a Joe Romm post. Rising CO2 is reflected in rising heat that will occur more in winter than summer, more at night than during the day, and more in northern latitudes like the Arctic than near the Equator. It appears that this picture has been complicated recently by research suggesting that the resulting decreased temperature gradient has compromised the strength of the jet stream, leading to colder temperatures from the Arctic driving down more towards the temperate zone and lasting there for a longer time period before a new front arrives.
Toggle Commented Apr 20, 2016 on Beaufort quick update at Arctic Sea Ice
Thx much NeilT, Roger, Bill, and AD -- all very good stuff. I should really bring this back to the Arctic, as Neven has been especially forbearing to let this discussion unrelated to the Beaufort go on this long. A few final notes that hopefully add to the discussion: (1) There's a fascinating movie under the NOAA site/CO2 emissions showing the spread of fossil-fuel-emission CO2 in the atmosphere from its original ground sources over the period 2011-12. The reason I think it relates is that it shows that strong Chinese emissions are carried by the trade winds across the Pacific in "flares" that occasionally cross Hawaii. It is possible that some of the ML anomalies over the course of a few days, in particular, are caused by intersection with a Chinese (or even Indian) flare. Note also that lesser hot spots in the US East Coast and Western Europe likewise flare across the Atlantic to Western Europe and China, respectively. I can't think why China would have such an outsized effect on ML right now, but it might explain why the ML upsurge has continued for more than a week. (2)I looked at the four years before and after 1998, and in fact CO2 growth rate was slightly larger before than after. It isn't until 2002 that CO2 growth rate kicks up to a decade-long 2-2.5 ppm/yr average growth rate, from a 1.5-1.9 ppm/yr growth rate before then. And so, given that the first half of this year should show outsized growth rates, I think it will probably be around 2019-2020 that any permanent increase in the growth rate will begin to be clear. (3) Many of my conclusions about the IEA data are reinforced by my experiences following the computer industry. For example: In the last 10-12 years, there was a massive shift in investment towards "developing countries" at IBM and other places -- primarily China and India, as well as the Philippines to some extent. These could offer much lower labor costs and theoretically a similar product. However, the infrastructure there -- electricity, heating, cooling -- did not have the capacity to support this and did not have the quality/efficiency standards that the US and Europe had. Therefore, the government had to rapidly increase capacity and use the existing inefficient infrastructure as a base with which to do so. To put it in a nutshell: Moving to developing countries showed up as increased profits in global businesses, but also increased CO2 compared to the same investment in developed countries. Moreover, these same businesses found it much more difficult to track their emissions in developing countries. Afaik, that was why, when Microsoft laudably committed to full tracking of its emissions and a goal of carbon neutrality a couple of years ago, it committed only to tracking and neutrality within the US. Now let me try to relate this back to the Arctic. The CO2 Emissions movie suggests that increases in CO2 at lower latitudes of the NH get transmitted first around the world at those lower latitudes, and then in a somewhat more delayed fashion to upper latitudes, i.e., the Arctic. So I would, as a swag, guess that increased heat over the Arctic due to the trailing edges of el Nino plus ff pollution would not only continue until fall, it might actually intensify, in the Beaufort as elsewhere -- and we might see what happened to temps in Greenland as the result partly of a "flare" from lower latitudes. It is even possible that this will result in an increase in the temperature gradient at the end of this fall, reducing the likelihood of extreme cold in the US/Europe the first part of next winter.
Toggle Commented Apr 19, 2016 on Beaufort quick update at Arctic Sea Ice
Sorry, I wrote this before seeing Roger's excellent research. I stand corrected on the equivalence of this el Nino and the 1998 one. - w
Toggle Commented Apr 18, 2016 on Beaufort quick update at Arctic Sea Ice
@Bill: First, thx for the "grok" reference. I must admit that I was a programmer for nearly 13 years before 1990 and never heard it used once. But it did show up in the New Hacker's Dictionary, which is a marvelous read for anyone who can find it. About the "anomalies": I must admit the scale of the jump last week is unprecedented in my memory, and I've followed CO2 ML since about 2010. Otoh, iirc, both Feb. in the global scale and Mar. in the ML scale showed about a 3.5 ppm increase; so this is clearly above even whatever happened in 1998. I can't rule out some extraneous effects nearby in Hawaii, although why they would surface now and not any other time in recent memory is beyond me. Re what's causing it: I am trying to write a blog post about it. I view effects from either oceanic upgassing or ocean/land capacity-reaching as less likely. CarbonTracker, I think, attempts to size these effects, and the effects it finds have been pretty stable for the last 15 years at least -- why should both not only change but change sharply at this time? Yes, the el Nino clearly is having an effect. But why should it have an effect that seems greater than 1998, and why does the effect linger when reports indicate that this el Nino has been no stronger than 1998 at its strongest, and has been weakening for at least 2 1/2 months? Finally, you have to take into account the fact that our best estimates of fossil-fuel pollution aside from CO2 ML and the like are done by the IEA based on self-reporting by national governments. It takes no conspiracy theory to figure out that the IEA estimates, which report ff pollution as flat over 2014-2015, are probably underestimating the rate of growth of ff-derived atmospheric carbon. Also probably the underestimate is increasing over time. Part of that self-report is from local governments, part from businesses, and the IEA does not track pollution during production of the fossil fuel. There is a natural tendency for such reporting to capture less as methods change and to avoid the job of reporting. Increased fracking is probably a cause of increased underestimation, since independent studies have shown large amounts of post-wellhead "flaring" (resulting in large methane/CH4 emissions). Heating/electric infrastructure has been shifting away from well-reported Euro and US zones towards China and India, and these also typically have less efficiency in electricity and heat usage than Europe/the US -- it's not clear whether the IEA deals with that problem adequately. NOAA's estimator shows that fossil-fuel pollution's positive carbon-pollution contribution measured at the marine surface grew from 9.14 ppm in 2011 to 9.78 ppm in 2014 -- there doesn't seem to be much of a slowdown in that in 2014. Putting together all this, if I had to guess, and I do: The IEA figures are wrong. European efforts are having an effect, but are counteracted by increases in China and India -- which are in turn caused primarily by US/Europe business investment. CO2 growth is real, and is caused partly by el Nino, but more by higher ff pollution and by feedback-loop effects in which, for example, exposure of the Arctic translates to increased black carbon on melting snow and possibly heat driven south that makes us use more electricity-based cooling (less efficient than heating).
Toggle Commented Apr 18, 2016 on Beaufort quick update at Arctic Sea Ice
NeilT: It's official. This week's value is 408.69, which is 4.59 ppm above last year at this time, and about 4.5 ppm above the maximum weekly value last year. Afaik, this is the first time the year-to-year increase in weekly ppm has ever topped 1%.
Toggle Commented Apr 17, 2016 on Beaufort quick update at Arctic Sea Ice
NeilT: You should also note that 3 weeks ago the Mauna Loa weekly average hit 405 ppm for the first time ever; last week the average hit 406 for the first time ever; and the first 5 days of this week are averaging about 408.7 ppm, with one day at about 409.4. - w
Toggle Commented Apr 17, 2016 on Beaufort quick update at Arctic Sea Ice
Hopefully this post actually gets through. Grok was introduced in Heinlein's Stranger in a Strange Land in the late 1960s, meaning (more or less) "to understand deeply and comprehensively." It was then adopted by hippie culture, and from thence moved into computer programming (hacker, in the old, good sense) jargon. It's good to see it again :)
Toggle Commented Apr 7, 2016 on Winter analysis addendum at Arctic Sea Ice
Hi Bill, I would agree with every point you have made. I would even make another: the alternative (non-Mauna Loa) metric tends to show much less fluctuation from year to year, and therefore will probably wind up less than 3.17. However, I will respectfully and with the utmost deference :) disagree with the conclusions you draw. Extrapolations from limited data are indeed dodgy. Thing is, they are dodgy upwards as well as downwards. In probability terms, there is an equal probability that I am too optimistic about what will happen if we do not make a significant dent in carbon emissions. Moreover, measured atmospheric carbon is a far more accurate indication of how things are really going than the per-country and global fossil-fuel emissions measurements you cite. To note a couple of examples, in 2009, because of the global economic recession, global measured emissions were down slightly, and have increased at slower rates since, with a net flat result in 2014 and 2015. During that time, carbon emissions increases have gone from the 1s to the 3s. The point is that our measurements do not capture well even the total of fossil-fuel emissions, while atmospheric carbon measurements capture everything. On a related but minor point: indications are that China's emissions did indeed go down last year, by the most effective method possible: the central authority told regional authorities to cut it out. And India's coal-use expansion is only beginning. And yet, atmospheric carbon increased a lot more than in previous years. The "physical causative basis" is not easily summarized, and afaik parts of it are not well understood. However, the point of Hansen et al's paper last year (summarized in a post on my blog as well as I could) is that in the past two episodes of global warming, atmospheric carbon increased or decreased at all points in the ratio (4 degrees C per doubling) I have cited, and other existing models have consistently underestimated that change up to a point, because they show "tipping point" or hysteresis behavior that is not there in the data -- they underestimate the effects up to the tipping point. So this is my long-winded way of saying that yes, atmospheric-carbon data sucks as a method of extrapolation; but it's the best method we have.
You are absolutely right. I stated the wrong conclusion from the chain of logic. Because of the lag time between carbon arrival in the atmosphere and the full effects of that arrival, an 8 degrees C rise would happen (assuming, again, continuation of "business as usual"), afaik, in the 2200 to 2300 time frame. With regard to the Paris climate talks, I share your hope that this marks a significant departure from "business as usual". My concern there is that despite Europe's relative success in achieving rapid decreases in carbon emissions, overall it does not seem to have had a significant effect on "business as usual" global carbon emissions, and therefore whether Paris has a significant effect in the next 10-20 years depends on how much solar displaces oil/coal/natural gas in global transportation and housing over that period. And if it does not do so adequately, we are still on the path of "business as usual" by the only metric that matters -- atmospheric carbon increases. I should also note, as per Joe Romm, that all estimates, including BAU, do not take into account permafrost melting. My own understanding of Romm's back-of-the-envelope calculation, assuming carbon dioxide rather than methane is the primary emission, is that this would add about 0.6 degrees C in the long run. This is factored into Hansen et al's model, which notes that two previous episodes of carbon atmospheric doubling involving permafrost melting resulted in a 4 degrees C temp increase per doubling.
Not sure this is on-topic but: The initial estimate for the 2015 yearly increase in CO2 as measured from Mauna Loa, Hawaii, is now available. It set a new record for amount of increase: 3.17 ppm. This was the first increase above 3, and was 0.25 above the second biggest increase (1998). It also represented the first time the increase had surpassed 2 in either three or four consecutive years. Increases in 1959-1964 averaged about 0.6 ppm per year, so that in the last 50 years the yearly increase has more than quintupled – a doubling approximately every 20 years. Projecting forward 40 years, the increase in 2055 would therefore be in the area of 12 ppm, and the total carbon in the atmosphere would be in the 600 ppm range, or more than double the pre-industrial value. Projecting forward another 40 years, the yearly increase would be in the area of 45 ppm, and the total carbon ppm in the atmosphere would be about 1040 ppm, or four times the preindustrial value. Acorrding to the estimate of James Hansen et al that each doubling of CO2 in the atmosphere historically corresponds in the long run to a 4 degrees C (7.2 degrees F) increase in global land temperature, and twice that in the far north/south, We are therefore talking about an increase of 8 degrees C or 15 degrees F from 1850 to 2100 on average and 16 degrees C or 29 degrees F in the far north/south.
Andrew Revkin is known for this kind of "your representations of scientific climate-change knowledge are exaggerations because I have my pet scientists" and "let's do something else instead" reporting -- if reporting isn't too kind a word. The Times had a superb climate-science reporter in Justin Gillis but took him off the beat except for occasional blog posts. Notice the bit about "why should they bother to keep fossil fuels in the ground" and the total disregard of folks like Ken Caldeira who have actually looked at these potential technologies.
P.S. I just took a look at the November CO2 figures (Mauna Loa). It's an almost unprecedented almost 3 ppm (2.89) increase from Nov. 2014 (the full year of 1998 saw a 2.93 increase, the only comparable full-year figure) -- and afaik that increase has nothing to do with el nino. That's just awful. It's hard not to get sick to my stomach with that one.
Hi Neven (et al), I really should have weighed in earlier -- other matters. James Hansen wrote extensively about the climate-change effects of aerosols in general a few years ago. From memory, this is what he said: increases in aerosols primarily from coal are counteracting (really, slowing) temperature rises due to climate change. However, this is true only as long as aerosol pollution continues to increase. If aerosol pollution levels off, temp rises start to act as if there is no pollution at all. If aerosol pollution decreases, temp rises are faster than the underlying carbon emissions. As Hansen also noted, there is a limit to how much aerosol pollution people can bear, and therefore at some point in the future people have to start decreasing their aerosol pollution. So all that has happened is that we have been lulled into a false sense that things are better than they are. A recent article at details what this means for the Chinese, who are now the primary aerosol polluters. Of particular note is that some of the pollutants can spread halfway around the world, giving Los Angeles an extra day per year of smog. I would suggest that the Arctic sea ice effects are simply part and parcel of the global effects. Less carbon pollution means more sunlight, heat, and global warming worldwide, not just in the Arctic. Side notes: According to a recent article in MIT Technology Review, India is caught between a rock and a hard place. To avoid uncontrollable violence, it needs to upgrade living conditions fast in a nation where 9/10 are still at poverty level, and that means coal. They are trying to move to solar as fast as they can, but practically they project increases in coal use for the next 5-10 years at least. With regard to technologies removing CO2 from the atmosphere, all technical articles I've read agree that deployment of these has been very slow to happen and significant effects of these are not projected for at least 5-10 years, if ever.
Delurk: I live in the area -- she meant 10-15 degrees Fahrenheit. However, on Tuesday and Wed. of this week it was 20 degrees F or 11 C above normal in Boston, setting a record both days.
Toggle Commented Sep 11, 2015 on PIOMAS September 2015 at Arctic Sea Ice
Much of this discussion appears to center around how to convey the correct amount of fear for the future and need to act far more forcefully now. I believe that the correct analogy is that of stopping a rock rolling downhill and gathering momentum as it goes. For example: Because of inaction and worse over the last 5-10 years, we have only a 25% chance of avoiding the completion of stage 1 (4 degrees C of global warming) and the onset of stage 2. Completion of stage 1 would doom us to more than ten million deaths from starvation and related effects -- a toll comparable to WW II -- primarily borne by developing countries but also causing significant hits to developed nations' economies. It would also quadruple the costs of avoiding stage 3. Avoidance of stage 2 would require constant-terms decreases of fossil-fuel-related carbon emissions by 5% per year over the next 15 years, and ruling out the use of 96% of coal reserves, 85% of oil/natural gas reserves, and all tar sands/oil shale reserves for the next 1000 years. Failure to avoid completion of stage 2 (8 degrees C and more of global warming) would doom us to more than 100 million deaths from starvation and global-warming-related disasters -- a toll greater than any in human history. It would again be borne primarily by developing nations, but developed nations are likely to see 1% or more of their populations similarly affected. The global economy is likely to see a drag of 1% per year from this, resulting in slightly more than stagnant economies in all cases. It would also quadruple the costs of avoiding stage 4 (worst case scenario). Avoidance of the onset of stage 3 would require constant-terms decreases of fossil-fuel-related carbon emissions by 2% per year over the next 35 years, and ruling out the use of 94% of coal reserves, 83% of oil/natural gas reserves, and all tar sands/oil shale reserves for the next 1000 years. Failure to avoid the completion of stage 3 (12 degrees C warming) would doom us to the deaths of more than 1 billion, 10-20% of the world's population, including 10% of developed nations' population. It would also quadruple the costs of avoiding stage 3, in economies and governments struggling with the costs of stage 2. The world economy would shrink to about 60% or its present level before stabilizing. Avoidance of stage 4 would require constant-terms decreases of fossil-fuel-related carbon emissions by 1 1/2% per year over the next 55 years, and ruling out the use of 88% of coal reserves, 67% of oil/natural gas reserves, and all tar sands/oil shale reserves for the next 1000 years. Failure to avoid the completion of stage 4 (16 degrees C warming, 28 degrees C in the far north and south) would doom us to the deaths of approximately 90% of human population, or 8 billion (assuming population growth as projected until 2050) from starvation, disease, war, poisonous fumes, and extreme weather. The world's present rich are projected to survive at only a 50% rate, and to be less rich than the military men who will take over. Most governments will collapse, and human population will center around growing crops in flammable, mosquito-ridden swamps in central Siberia, northern Canada, and small segments in Manchuria and northern Argentina. For six months of the year, for all except high-altitude populations, work outdoors would be effectively impossible. Economies would be inefficient due to dominance by the military. Avoidance of stage 4 would require constant-terms decreases of fossil-fuel-related carbon emissions by 1% per year over the next 60 years, and ruling out the use of 83% of coal reserves, 50% of oil/natural gas reserves, and all tar sands/oil shale reserves for the next 1000 years.
Toggle Commented May 16, 2015 on Bill McKibben nails it at Arctic Sea Ice
Hi Neven, Chris. Thx for insight as always. Actually, Neven, those two comments were hopefully just repeated in my third one. So, not necessary to resuscitate those posts, but much appreciated. Fyi, my last two comments went through when I logged in to typepad via Facebook. Apparently, your spam filter regards the Facebook "brand" as spam-free :) Chris, I appreciate the insight on the paper. My old crude model (now, alas, probably discredited) suggested to me that there would be no tipping point or hysteresis, and Hansen's review of data from 3 million years ago found that the Arctic was ice-free year round at 360 ppm atmospheric carbon, but this is a unique situation, so I wasn't sure.
Thoughts on McKibben: He notes 3 places where sources of carbon pollution are best left underground -- keystone/Canadian tar sands, the powder basin coal, and Arctic oil. The key with regard to Keystone is that it is a "gateway drug", creating infrastructure to handle shipping tough-to-handle oil. It is therefore good that so far Obama has been resisting going ahead with it; but that oversight should also be applied to other tar-sands/oil-shale shipment efforts that so far the US government has let go ahead. With regard to Shell and the Arctic, it is indeed foolhardy to let Shell drill; but so far, Shell has failed to handle the Arctic weather, and there is good reason to suspect that it will do so next season, so there is at least a case that the permit may simply cause Shell to fail and defer its plans for another few years, when the political consensus will be better. I agree there's major environmental damage in the meantime, but the key is whether significant amounts of oil wind up being shipped. It's the Powder Basin case, about which I know little, that really concerns me. According to my take on James Hansen's calculations, the politically feasible way of avoiding his "worst case scenario" is to leave all but about 7-10 % of the coal in the ground. If Powder Basin represents a significant amount of remaining coal reserves, that would mean a major threat of the "worst case scenario." (cf a blog post I did last year) Let me close on a personal note. I have been a lifelong Democrat (and liberal, for those of you who know what that word really means). If Keystone is approved or something else that threatens to lead to "maximum feasible benefit", I will no longer be a Democrat, as no matter what they do both parties will lead us to "worst case scenario". I will, instead, vote for a Green candidate, whether there is one or not.
Toggle Commented May 14, 2015 on Bill McKibben nails it at Arctic Sea Ice
@Neven - typepad ate my last post. Try again. I can't share your feeling that "reversibility" is good news. Here's Joe Romm summarizing: "The interesting conclusion from the study from the scientists’ viewpoint (and Scripps’) was that a more sophisticated model of the Arctic found that contrary to previous models, the ice loss is not, technically, irreversible. If you could somehow reverse temperatures on the earth, the ice would come back. But in practice it is all but impossible to get temperatures back down again. Heck, we’ve got another 1° Fahrenheit baked in just because it takes a while for the climate system to come into equilibrium. And unless we cut global greenhouse gas emissions to zero by mid-century, we can’t avoid another 1°F after that. And, unless we stop listening to climate science deniers like those at the Daily Caller, we will add another 5°F or more after that. Bye bye summer ice and possibly virtually all the ice year-round! The scientific literature is quite clear that warming-driven temperature rise is irreversible on a time scale of centuries. As the world’s top scientists explained in November in their final IPCC synthesis report summarizing the scientific literature: “Surface temperatures will remain approximately constant at elevated levels for many centuries after a complete cessation of net anthropogenic CO2 emissions”!" Also, I think that Joe is underestimating the amount already "baked in", because according to a recent Hansen draft study, 1/4-1/3 of warming comes not from carbon but from accompanying increases in black carbon and methane plus albedo change. By this measure, about 2.3 degrees Centigrade of warming is already "baked in" at 400 ppm carbon, or an additional 2 degrees F.
Sorry, but as presented the argument seems clearly flawed -- perhaps fatally. You are, it appears, talking about a wealth, not an income, tax. Such taxes must factor in a long-term better return that inflation that effectively yields approximately 9% per year after inflation for stocks, and 1-3% for bonds. With an index fund to diversify, therefore, an 8 % return on investment after inflation is indicated. To achieve a disincentive for keeping things in capital as opposed to "consumption" (which is not a realistic option for a billionaire), you would have to therefore have a 7-8% tax on total wealth. If you see such a thing out there, let me know. And no, you don't get to argue that capital gains taxes involve taxing things twice -- a careful analysis shows that after careful assessment of just who owns what and net present value effects, the additional tax burden is minor. Finally, because the "capitalist" is concerned with returns to capital, and income/returns to labor are minor to him, it is in his interest to drive the capital rate far below where it should be -- because he is not rational -- or believes that this "capital monopoly" is actually better for him. To put it another way, he will simply seek to offload all taxes on someone else and will accept a monopoly "overshoot" from the government market he controls.
Naive question for dorlomin: "bang on" -- are you talking about extent? It appears from NSIDC that antarctic melt is skewed from normal, as if circumpolar currents are able to rotate the ice more than usual. This could be explained if sea ice is more fragmented than usual (i.e., less area than usual), allowing the current to push the edges of the ice farther, before and after the peninsula. This, in turn, would mean than more ice is "spun" off into lower latitudes, increasing the amount that melts during the summer season.
Toggle Commented Nov 24, 2010 on Open Thread 2 at Arctic Sea Ice
I hate to weigh in on this, but over the past 3 months I have been reading some of the literature, including Heidi Cullen's Weather of the Future, Peter Ward's The Flooded Earth, and James Hansen's Storms of my Grandchildren (the key quote there is something like "if we use up all our present fossil fuel resources (oil, gas, coal) there is a significant chance of a runaway greenhouse gas effect. If we also use up all the oil shale and tar sands, I view [runaway greenhouse gas effect] as almost certain." Put together with some of the research noted on, these publications by scientists do indeed lay out a possible path to extreme disaster. Here is a scenario (heavily shortened, some of details deduced): Stage 1: Disaster 2010-2050 (worst-case) Drought affects most of area south of northern Canada, Scandinavia and Siberia. Excessive heat makes low-altitude tropics and south of temperate zone above the equator uneconomic to live in, including parts of US South/Southwest, Mediterranean, Southeast Asia, and Southern China. Rising sea level and increased storm surge effectively makes Miami, New Orleans, Galveston, Boston, south New York City, most of Holland, and almost all of Bangladesh uninhabitable. Flash-flood amount and hurricane-force increases make effective home insurance in all areas skyrocket. More than 500 million people move, and perhaps 5 million die as a result of all of the above. Stage 2: Tragedy Severe drought affects most of area south of northern Canada, Scandinavia, and Siberia. Oceanic dead zones make Caribbean, Pacific islands effectively uninhabitable, and reduce availability of fish drastically as food source. Drying of major rivers from reduced snow/ice and drought, and/or loss of estuaries from rising sea levels, especially the Amazon, Ganges, Nile, Mississippi, Indus, Yellow. Rising sea level to about 25-50 feet of increase makes most of Florida, much of New York City, Long Island, Cape Cod, Washington, DC, London, Los Angeles, Seattle, Denmark, Tokyo, parts of Chinese coast, Alexandria, parts of Australia uninhabitable. Melting of permafrost and 20 degrees rise in temperature make northern Canada and Alaska, Siberia, and parts of Greenland habitable but difficult to travel in. 30% of ocean species and 30% of land ecosystems become extinct, beginning to reduce available food. More than 1.5 billion people move, and perhaps 100 million people die as a result. Stage 3: Murder Total increases in global average temperature reach 20 degrees F, making many areas in southern US, India, northern Africa, northern Australia, the north coast of South America, effectively uninhabitable. Sea level rise to about 120 feet makes most of east/west/south coast of US, Mediterranean and Atlantic European coasts, most coasts of England, parts of Brazil and India, the coasts of China and Japan uninhabitable – involving the present residence of perhaps 2 billion people. More than 1 billion people move, and perhaps fifty million die as a result. 70% of all species become extinct as oceanic dead zones spread and remainder of land ecosystems that cannot migrate north/south vanish. Increasing downward shocks to the global economy due to reduced availability of fossil fuels (because of less international trade) and decreases/movements in arable land lead to massive famines and inability to cope with famines, which in turn lead to the death of 1 billion. Stage 4: Collapse/Extinction Total increases in global average temperature reach 25-30 degrees, making most of existing tropical zone and much of existing temperate zone either unlivable or uneconomic to live in. Sea level rise reaches its maximum at 240 feet; almost the entire Earth is ice-free. Further migration from coasts, including Black Sea and Canadian and Siberian Arctic. Few humans in Australia, northern 2/3 of Africa, Middle East, most of India, Southern and western China, Southeast Asia, almost all of US, northern coasts of Latin America, Mediterranean, area of Black Sea. Oceanic dead zones continue to spread, beginning to endanger Arctic fisheries. Loss of additional arable land and beginnings of decreased productivity from the remaining arable land due to over-production, leading to additional famines and the death of another 1 billion. Addition of low-oxygen water to oceans creates new bacteria whose huge release of hydrogen sulfide poisons residents of seacoasts and breaks down ozone layer, leading to an additional 20% species extinction and 1 billion more human deaths (Medea hypothesis, Ward, as evidenced by some geologic data). Stage 5: End of Life on Earth Human burning of all fossil fuels, including tar sands and oil shale, makes carbon in atmosphere reach a “tipping point” that triggers runaway greenhouse effect that cannot be stopped (James Hansen, “Storms of my Grandchildren”). Oceans become so acid that in most areas they cannot support life. Eventually, land temperatures become hot enough to prevent most vegetation from growing, and carbon cannot be sequestered, since the ocean will not create limestone; so it stays in the atmosphere. Massive methane and carbon releases from permafrost drive carbon in the atmosphere, and therefore the temperature, far higher (note: this may occur in stage 4). Somewhere after this point, the oceans will boil, the atmosphere will become unbreathable (primarily carbon), and most life on earth will become extinct – including humans. Extremely high surface temperatures will eliminate the rest of life on Earth, leaving a planet much like Venus. Please note: as we have been for the last 30 years, under "business as usual" we are now on a path to 1100 ppm carbon in the atmosphere by the end of this century, which would effectively take us almost to the start of Stage 4. Also, geo-engineering may save us from stages 4 and 5; but so far, it is not clear how.
Toggle Commented Nov 24, 2010 on Open Thread 2 at Arctic Sea Ice
Wayne Kernochan is now following The Typepad Team
Nov 24, 2010