totally different issue ________________________________
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Sent: Wednesday, October 22, 2008 4:31 PM To: [EMAIL PROTECTED]; Hawkins, Dave; [EMAIL PROTECTED]; Alvia Gaskill; Geoengineering Subject: Re: [geo] Re: MIT Prof Says Use Geo As Last Resort Historically the habitable coasts were ice free 1000 years ago. Sent via BlackBerry by AT&T ________________________________ From: Mike MacCracken <[EMAIL PROTECTED]> Date: Wed, 22 Oct 2008 16:26:01 -0400 To: David Hawkins<[EMAIL PROTECTED]>; [EMAIL PROTECTED]<[EMAIL PROTECTED]>; Alvia Gaskill<[EMAIL PROTECTED]>; Geoengineering<[email protected]> Subject: [geo] Re: MIT Prof Says Use Geo As Last Resort Actually, for the northern half of Greenland, coring indicates that the ice goes back over 200,000 years before layers are so crushed it is hard to differentiate older layers. For southern half, goes back to 110-120,000 years, so to the last interglacial (the Eemian) when orbital parameters caused summer temperatures to be several degrees warmer than at present (though global average temperature was, some suggest, about 1 C higher than present) . No way was most of Greenland gone 1000 years ago-sea level would have been 20 feet higher than at present, and having visited Phoenician salt flats in Sicily last year that are something like 2800 years old and just starting to be overwashed, there is clear evidence that not much of Greenland could have melted at any time over last several thousand years, at least. Mike MacCracken On 10/22/08 3:53 PM, "David Hawkins" <[EMAIL PROTECTED]> wrote: >One need go back only 1000 years to find an extensive 'natural' warming event that completely melted the Greenland ice sheet. I'm not sure what you intended to say but the ice at the base of the Greenland Ice Sheet has been dated as > 110,000 years old. ________________________________ From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of Eugene I. Gordon Sent: Wednesday, October 22, 2008 11:38 AM To: [EMAIL PROTECTED]; [email protected] Subject: [geo] Re: MIT Prof Says Use Geo As Last Resort To All: The risk from increased acidification of the ocean as a result of increased CO2 concentration in the atmosphere is troublesome and points to the need to do something about manmade CO2 emissions or finding ways to reduce CO2 concentration in the ocean (a geoengineering fix as is being discussed). That acidification problem is serious but probably not as serious as global warming. If AGW was only minor and not apt to produce major problems how much would the acidity fix be worth? I am amused that Dr. Prinn notes the correlation between previous warmings and rising CO2 levels (in the absence of man's input) but does not draw the obvious conclusion as to cause and effect. Here is a more interesting problem in my opinion and what Prinn totally misses. Suppose the world got together and decided to fix the manmade greenhouse gas emissions problem, eliminating all fossil fuel use or related emissions and capping methane gas emissions from cows, sheep etc. For sure that would not eliminate the possibility of serious global surface temp.warming or cooling since there are at least 5000 years of geological data showing that such occurs; maybe 20 such events, sometimes far worse than is currently being experienced. One need go back only 1000 years to find an extensive 'natural' warming event that completely melted the Greenland ice sheet. (Incidentally, there were plenty of fish in the ocean during the Greenland warming period despite what was probably high ocean acidity, the Portuguese sailed all the way to Canada to get super abundant cod.) The cause of such events is unknown except that sunspot variations are suspected; especially because of perfect correlation over the last 500 years between sunspot counts and warming or cooling periods. Indeed sunspots are also suspected to be a factor in the current warming.but the degree is unknown. Currently we cannot control sunspots, so even in a perfect world in which man contributes virtually nothing to the greenhouse gas concentrations there is a serious future need for control of the global average surface temperature and ocean acidification. That need exists now as well for whatever the current reason(s). Thus, a good geoengineering fix is not only a contingency for now but an absolute essential for the future manmade greenhouse gas emission-free world. Why does someone as knowledgeable as Prinn miss this point? Why does this group miss this point and why are we not beating the drums loudly to get the funding to develop the necessary technology? -gene ________________________________ From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of Alvia Gaskill Sent: Tuesday, October 21, 2008 8:24 PM To: [email protected] Subject: [geo] MIT Prof Says Use Geo As Last Resort http://www.canadianconsultingengineer.com/issues/ISarticle.asp?id=91030 Canadian Consulting Engineer, 10/20/2008 ________________________________ MIT professor bombards engineers with evidence of climate change At the Ontario Society of Professional Engineers' symposium held October 16 in Toronto, Dr. Ron G. Prinn of MIT presented slide after slide, with graphs, maps and explanations about the reasons why we should take climate change problems seriously. There is so much information and media coverage about global warming now, it's easy to start mentally glossing over the issues and pushing them to the margins of our consciousness again. But faced with the dense layers of evidence that Dr. Prinn presented, the audience was shocked back into realizing the seriousness of this environmental problem. Prinn has an astounding depth of personal knowledge (he spoke without any notes), happily combined with a rare ability to explain complex issues in reasonably accessible terms. Certainly he caught the attention of 150-or so engineers and engineering students in attendance and seemed to win their agreement - there were no hecklers or naysayers to be heard. Dr. Prinn is the TEPCO Professor of Atmospheric Science at the Masachussetts Institute of Technology (MIT). He has a team of 40 people researching and modelling climate change and its economic effects. He is a member of the United Nation's Intergovernmental Panel on Climate Change, and he has testified twice to the U.S. Congress about climate change and its implications for policy. (At the end of his talk, he suggested "things are changing in the U.S." with regard to efforts to deal with the issue and said that both U.S. Presidential candidates take climate change seriously.) Prinn said there are lots of uncertainties in predicting the effects of the build-up of carbon dioxide and other greenhouse gases, but by working with "large ensembles" of computer models they can make reasonable predictions. Insofar as predicting the effects on particular geographic regions, he said the computer models are converging at the continental and sub-continental scale, but at a local level it's more difficult. He also said that the biggest areas of scientific uncertainty are in the effects on "clouds; ocean mixing, and aerosol 'forcing.'" At present we are warming the earth by 1.6 watts per square metre, Prinn said, which translates to 816 TW worldwide, which is equivalent to 52 times the current global energy consumption. He showed evidence from ice core samples from the polar ice fields that showed a correlation over four glacial cycles between rising carbon dioxide levels in the atmosphere and earth's surface warming. He said sea ice is currently shrinking at record levels, and nature is speeding the process up in a series of feedback loops. If temperatures around the globe rise by 4 degrees C, those in the polar regions will go up by 8 degrees C (the effects in the polar regions are double), and there will be a 5 metre rise in sea levels. If the tundra permafrost melts, it will release huge amounts of methane, equivalent to 80 times our current annual emissions of greenhouse gases. What came across overall from the mass of data and statistics was the interrelatedness and delicate balance of the whole global and atmospheric system, operating as it does on a series of feedback loops. So when someone asked Prinn what he thought about "geoengineering" solutions such as putting mirrors up in space to deflect sunlight, he was cautious. He said that we should only resort to such measures in extreme circumstances, because frankly, the globe is a very complex machine and we don't understand fully how it works. Prinn had some comments on current efforts to reduce our greenhouse gases. First, he said: "Make sure the engineering is working well on the large scale." He said that achieving efficiencies in the buildings and transportation sectors are important. These sectors are "the business of engineers" and fully "one third of the solution." He suggested that for dirty fuels like coal and the oil sands, we have to have carbon capture and storage. Biofuels are a solution, but using cullulose, not corn, and only using material grown on existing grasslands. With wind power, he said the MIT team's research shows offshore wind farms are the most promising; on-land turbines can cause local warming effects if they are not spread out and lined up properly. He talked about a solar farm in the Sahara dessert that was actually found to be increasing temperatures in the vicinity because the photovoltaic units were black and absorbing the heat. The answer was simply to add white reflector panels beside the units. On the question of economic instruments, Prinn seemed to have little time for carbon trading. His answer was simple: "All you need to do is put a price on carbon emissions," he said. No virus found in this incoming message. 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