MIT professor bombards engineers with evidence of climate change
October 20, 2008
By Canadian Consulting Engineer
At the Ontario Society of Professional Engineers' symposium held October 16 in Toronto, Dr. Ron G. Prinn of MIT pre...
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.