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Published online 29 April 2009 | Nature | doi:10.1038/4581091a
Climate crunch: A burden beyond bearing
The climate situation may be even worse than you think. In the first of three features, Richard Monastersky looks at evidence that keeping carbon dioxide beneath dangerous levels is tougher than previously thought.
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What a wonderful article. "The climate situation MAY BE even worse than you think." If you think its worse, that is. An "environmental writer" approaches a "climate scientist" with a question about safe levels of atmospheric CO2. The scientist who has spent his career working on climate models and proclaiming the purported dangers of CO2 at the top of his voice, doesn't have a clue, but does further research with his models, which he recognises are his "weakest tools" and by jove - things are even worse than those forecasted by his previous models. What then does he do? What any politician would do. Dress up in his overcoat, to ward off pneumonia from the cold, along with the writer, and demonstrate against global warming (lovely picture caption btw). This was wise since cold related deaths are far more numerous than heat related deaths in all countries outside the tropics. Not only that but the BBC informs us under a caption GLOBAL WARMING 'MAY CUT DEATHS', that while While summers in the UK became warmer in the period 1971 - 2003, there was NO CHANGE IN HEAT-RELATED DEATHS, but annual cold-related deaths, which far outstrip heat-related mortality, declined. Its not surprising that these doom and gloom climate scientists are beginning to look like a bunch of Noahs. Religion and faith is on the decline.
I still haven't seen any published scientific evidence that CO2 is a pollutant or can cause all the dreadful things Dr. Hansen can predict. Hansen,et al, go in with the assumption that CO2 is the cause of global warming. They did not LOOK for any other cause. And they refuse to even acknowledge the possibility that there may be one. This is not science. This is religion and politics. Science is NEVER "done". At present, our knowledge of the factors relating to climate change are rudimentary at best. Too many variables have not been fully explored. And if someone can present evidence, verifiable evidence, that this is not the case, please do. It would save a lot of hot air!
Bill, there is actually ZERO scientific evidence that CO2 EVER caused global warming in our 4.5 billion year history and massive scientific evidence that the Sun, directly and indirectly has been the prime mover of our climate. This should be common sense but the sun has been conveniently swept under the carpet, so to speak. The ice-core data going back hundreds of thousands of years show that CO2 ALWAYS followed global warming by a lag of several centuries. Our climate has forever been changing and will continue to do so. The anthropogenic global warming industry and religion has spread this scam and swindle to invent and promote its own business. Our dominant climatic feature for the past 2 million years has been the ice-ages, punctuated by brief periods of about 10,000 years of warmth, for which we should be eternally grateful. There is NOTHING unusual about the present warm period. For a rational and balanced scientific view please listen to Bob Carter of Australia over here http://www.youtube.com/watch?v=FOLkze-9GcI this is the first of a 4 part video. I invite you and other viewers to listen to all of them.
Richard, I'm certain that the hundreds of millions of people whose communities will be under sea level are, indeed, eternally grateful.
Asher your comment makes no sense, switching as it does from future to present tense. Perhaps what you mean is that millions of people ARE indeed eternally grateful now that they realise that THEY WILL NOT BE under sea level as claimed by some scare-mongering climate scientists, without any scientific basis, who are at best mistaken and delusional, and at worst fraudulent. Go here for a little lesson - http://www.youtube.com/watch?v=-zeGY8zbzc8 and here http://www.youtube.com/watch?v=0BmWy6Nsm6I&feature=related
Bill and Richard: for people who would fail basic atmospheric physics classes, I'm rather perplexed you spend the time to read Nature.com... I mean, it's great to see. Still, you'll get much more out of it if you "learn" a bit. And, you'll save valuable space in the comments section. Let me provide you will a start: If CO2 "never" caused warming in the "4.5 billion year history", the Earth would be 34 degrees colder than it is (Kelvin or Celcius scale). If that happened, life as we know it could not exist. You owe your lives to CO2-induced global warming!
Mr. Monastersky, Acceptance or rejection of Anthropogenic Global Warming by a given individual is more a result of political persuasion than scientific rigor. That's obvious from the posts here and elsewhere. Personally, I accept that it is clearly true: people burning previously sequestered fossil fuels have raised concentrations of CO2 in the atmosphere. BUT I also wonder if it will be as catastrophic as is often projected my progressive people. The reason I wonder is the cycle of ice ages. I understand that the wingnuts use it as "proof" that the globe is cooling RIGHT NOW!!!!!! This instant!!! Look at the rain outside!!!! That's predictable and laughable neo-Con stupidity. However, it is pretty indisputable that we are at the end of one of the 10K year climatic optimum. During this warm time humans have colonized the entire globe while previously we were limited to Africa and the coasts of the always warm Indian Ocean. Is it not possible that both sides of the fight have a piece of the puzzle? That is, AGW supporters are correct that assuming no change in insolation rising levels of CO2 would lead to catastrophic sea-level rise, the expansion of tropical pestilence, and a generally miserable time for humans and our fellow creatures. But might it not also be true that insolation is truly due to decline and that wrapping the Earth in a blanket of carbon dioxide might ameliorate the effects of the coming ice age? I realize that this is similar reasoning to that of the "geoengineers" who would like to mistify (purposefully misspelled) the Earth in order to cool it. It's obviously dangerous to tinker with the atmosphere, even by omission.
Great article. But I am confused about one paragraph in yourarticle. Under the section "Slow Recovery" (p. 1093), you summarize the accompanying Meinshausen et al. article, stating "For the period 2000 to 2050, they find that the world would have to limit emissions of all greenhouse gases to the equivalent of 400 gigatonnes of carbon in order to stand a 75% chance of avoiding more than 2 °C of warming." However, I can't find the 400 GT figure in the Menshausen et al. article. Instead, they say: "we find that the probability of exceeding 2 °C can be limited to below 25% (50%) by keeping 2000?49 cumulative CO2 emissions from fossil sources and land use change to below 1,000 (1,440) Gt CO2" Where does your 400 GT figure come from?
Are we effectively approaching a transition zone from 'Oligocene to Eocene' ?
Pre-industrial era, CO_2 has been considered as ~280 ppm. Current value is 387 ppm. http://en.wikipedia.org/wiki/Greenhouse_gas
Some projections are for CO_2 to rise to ~540-970 ppm by 2100 (90 yrs away). http://en.wikipedia.org/wiki/Global_warming. Upper range of 970 ppm would represent 2.5 x current value. Would this represent an accelerating curve?
Are we increasingly accelerating through a transition zone, effectively in reverse, from 'Oligocene to Eocene' ? The Eocene to Oligocene transition 35 million years ago http://en.wikipedia.org/wiki/Eocene has been estimated to occur at ~750 ppm of CO_2. http://en.wikipedia.org/wiki/Eocene. http://www.nature.com/nature/journal/vaop/ncurrent/abs/nature08447.html. Paleocene-Eocene was a greenhouse time of probably essentially no ice on the planet. http://en.wikipedia.org/wiki/Paleocene%E2%80%93Eocene_Thermal_Maximum. For subsequent Oligocene one has cooling and onset of glaciation. If indeed the current upper limit projections of 970 ppm is reasonable, might one have commencement of melting of East Antarctica in 100's of years, rather than thousands of years? With perhaps a lower limit of 100+ yrs before any significant melting of East Antarctica?
Total surface area of ice in all of Antarctica (east and west) is ~ 13,720,000 km^2, with
average thickness of 1.6 km.; giving ice volume of 21,952,000 km^3. http://en.wikipedia.org/wiki/Anarctica.
Ocean surface area is 361,132,000 km^2 (70.8% of planet surface area). http://en.wikipedia.org/wiki/Oceans.
Volume_ice /S.A._ocean = h ~ 22 M km^3/ 361 M km^2 = .06 km.
Thus for total melting of all of Antarctica, and even distribution over all oceans, one would have increased sea level rise of .06 km. 1 meter is 3.28 ft.1000 m.=3280 ft. So .06 × 3280= 199 ft sea level rise. But if West Antarctica's earlier contribution is ~11 ft (3-4 m.), then sea level rise from later process of East Antarctica complete melting, would be ~ 188 ft or 57 meters. 100 meters equaling 328 ft. Would prudence suggest entertaining and planning for a worse case scenario?
Paul N. Pearson, Gavin L. Foster, & Bridget S. Wade
Nature 13 September 2009
Atmospheric carbon dioxide through the Eocene-Oligocene climate transition
Re: A testable model addressing the issue of East Antarctica ice sheet stability?
As above: If the Isthmus of Panama were opened by significant rising sea level, then Gulf of Mexico waters might egress to Pacific. This would then seem to disrupt the Gulf Stream. Hence one could also obtain sea bed cores from south more proximal aspect of Stream to see if there has been disruption of flow. This could be compared to Panama Isthmus findings, and also could serve as a proxy for significant sea level increase from East Antarctica dissolution.
For record of foraminifera for < 3 million years, one has oscillations of glaciation cycles. This approximately corresponds to geological closing of Isthmus of Panama at ~3 M yrs. [URL="http://www.nature.com/nature/journal...ture01089.html"]http://www.nature.com/nature/journal...ture01089.html[/URL] Northern ice sheet formation would seem dependent on warm water with higher evaporation and subsequent percipitation. [URL="http://www.nature.com/nature/journal...ture01089.html"]http://www.nature.com/nature/journal...ture01089.html[/URL] Thus a history of cycles of N. ice sheets would seem consistent with persistence of Gulf Stream; and hence consistent with persistence of closure of Isthmus of Panama. Such persistence of Isthmus of Panama (84 ft elevation) would seem consistent with no sea surface elevation of ~180 ft. Hence cycles of glaciation, persistence of Gulf Stream, would seem consistent with no complete melting or dissolution of East Antarctica. Thus via indirect evidence, East Antarctica would seem to be historically stable.