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Two days ago I attended an interesting public talk with the above title given by David Keith,  Gordon McKay Professor of Applied Physics at Harvard and Professor of Public Policy at the Kennedy School. The talk was sponsored by the Global Warming Action Coalition (GWAC) of Lexington.

The following is my “take away” from this talk. First of all, what is “Geo-engineering?” Answer: it is the use of engineering techniques to implement changes in the natural world, e.g., reduce global warming.  Climate change and global warming is pretty much an established scientific fact. Furthermore, even if we stop any further carbon generation, it will only decrease the carbon level by 1/3 in 1000 years. This is inertia. Since we do not know for sure how bad or very bad the ultimate damages of global warming, this uncertainty plus the carbon inertia spells grave danger to our civilization in the long term. Question: what can we do about it? Answer: According to the speaker it turns out at least in the short term there exist a rather simple and lower cost way (in theory) to cool down the planet and counter the warming effect of carbon. Currently we generate and dump about 50 tons of sulfur particles into the lower atmosphere per year from various sources. Now if we can deposit just one ton of sulfur particles into the stratosphere per year, then they will reflect enough sunlight out to space before it warms the earth to eliminate global warming. We only need a small fleet of airplanes to accomplish this feat. So why isn’t this done tomorrow. Reasons:

1.     Full scale testing needs to be done to prove the concept

2.     This is only a short term solution we cannot continuously dumping carbon and sulfur into the atmosphere non-stop even if the solution is successful. We may get a false sense of security and stop long term solutions.

3.     If one geo-engineering task is successful, people will clamor for more way to alter nature without thinking through all the consequences. Geo-engineerin (just like global warming) has very complex implications and unintended results that are difficult to foresee. Note added 10/28/12. Today's NY Times has an article about the myriad and complex effects of geoengineering. http://www.nytimes.com/2012/10/28/opinion/sunday/geoengineering-testing-the-waters.html?ref=todayspaper&_r=0

Interested reader should go to Keith’s website for more details and videos.

http://www.keith.seas.harvard.edu/

http://www.keith.seas.harvard.edu/opeds.html

David Keith works at the interface of climate science, energy technology and public policy. He is a leading world expert on geo- engineering , won MIT’s prize for Excellence in Experimental Physics and was listed by TIME Magazine as a Hero of the Environment.  He is a dynamic and challenging speaker and will speak on a subject on the forefront of climate change research.

 “We can always count on GWAC to be ahead of the curve and engage the greater community on the most urgent elements of the climate crisis.”

         —Kevin Knobloch,  President of Union of Concerned Scientists

 “Geoengineering may prove to be the last card we can play in dealing with climate change. There is no better person to tell us about this exciting and controversial new field than David Keith. “

—Kerry Emanuel, Professor of Atmospheric Science, MIT, and Lexington resident