Sorry about the light blogging. I was participating in an interesting conference in Kyoto called Science and Technology in Society with a very interesting international mix of scientists, politicians and business people. There were lots of really interesting presentations from some really smart people. I'll try to post more later, but here are some notes from a lunch speech by Sherwood F. Rowland, Donald Bren Research Professor of Chemistry and Earth Systems, University of California at Irvine and Nobel Laureate in Chemistry (1995).
The population of the world is about 6B now and it is expected that it will stabilize at around 9B in the middle of the century. We've grown from 3B to 6B in the last half century so we've done this before. We output about 6B tons of carbon dioxide. That's an average of 1 ton per person. In the US the average is about 5 tons per person and in India and Nigeria it's about 0.2 tons per person. If you added the US and population to India's population, it would be about 1.4 tons, or approximately the rate at which Albania creates carbon dioxide. 85% of our energy comes from fossil fuels, coal, gas and oil which create carbon dioxide. These are green house gasses. In 1800 there was about 280 parts per million of carbon dioxide and 800 parts per billion of methane in the air. Today we are at about 380 parts per million of carbon dioxide and 1750 parts per billion of methane.I was scribbling notes during lunch and I may have mangled some of this. Please let me know if I've misquoted something and I'll fix it.
A calculation of the natural greenhouse effect of the earth is 32 degrees centigrade. The enhanced greenhouse effect puts us at more like 33 to 37 degrees centigrade. The average temperature of the earth has increased 6/10th of a degree in the last century. The warmest days since we have begun recording temperatures about 150 years ago have all been since 1990. In order to stabilize the increase in carbon dioxide (at a much higher level than it is now), we would need to cut back 60% of our output. Conservation can help, but it is unlikely that conservation itself can take us to a sustainable situation. Alternative carbon free energy sources like solar, nuclear, and wind must be explored, but we must understand that we are in a situation that requires immediate action.
One important "take-away" from this meeting was that global warming and the risk did not seem like some sort of disputed theory as some politicians seem to lead us to believe. All of the scientists involved in energy and ecology that I heard speaking seemed to believe that our earth was immediately at risk and that we had to act now. The combination of the increase in population and our addiction to energy would not allow us to stabilize at any sustainable equilibrium without drastic changes in the way we make and use energy.