Projections of future climate change, based on complex climate models and on our best understanding of the physics of the climate system, suggest a rise of another two to six and a half degrees Fahrenheit by 2100, with an average increase greater than any seen in the last 10,000 years. This warming will not be uniform - it is likely to be greater at higher latitudes and at the poles. Based on these warming trends, sea level is projected to rise an additional one and a half feet by 2100 due to thermal expansion of the oceans and to the melting of glaciers and ice sheets. This would, without adoptive measures, flood 9,000 square miles of coastal areas here in the United States, notably in Florida and Louisiana, and put about 100 million people world-wide at risk each year from storm surges. In other words, the path we are on is cause for significant concern.
Climate change is likely to have wide-ranging and mostly adverse effects on human health.
Both natural and managed ecosystems are at risk. The viability and location of forest and agricultural zones will change significantly. Moreover, virtually all the studies on the effects of climate disruption have focused on predicted doubling of atmospheric concentrations of greenhouse gases. But unless significant actions are taken early in the next century, it is very likely that atmospheric concentrations will, by the year 2100, nearly triple the pre-industrial level and rise higher than any point in the last 50 million years. Let me now move on to the division of responsibilities between developed and developing countries.