Posted by Menas Kafatos
It has become clear that there is a lot that needs to be studied about the changing climate of the Earth. Many scientists are concerned that the Earth is changing faster than the forecasts of the IPCC. This view was expressed at COP15, by European scientists and politicians, with somewhat obvious points being made that the polar ice is melting faster than the models predicted, the glaciers are similarly receeding faster than anticipated, etc. However, an equally appreciable section of scientific opinion is questioning whether some of the predictions about global warming have been overstated. According to the BBC (http://news.bbc.co.uk/2/hi/science/nature/8423822.stm), a survey a while ago showed that 18% of scientists thought the Intergovernmental Panel had exaggerated, while 17% of scientists thought the IPCC had under-stated the risks, and the rest of the scientists thought they had got it right. So there is still appreciable division among scientists. This of course does not mean that nations should do nothing just because there is still considerable uncertainty. On the contrary, scientists should make renewed efforts to quantify the uncertainties and to not take for granted that predictions are settled.
In this respect, it is important to emphasize that in the end, more observations are needed, such as provided by global Earth observing systems. The global models need to continue to be improved. Much is missing, such as non-linear effects of regional processes, the effects of aerosols and pollution, how regional climate couples to the global system, etc. Making things simpler by linearizing important processes in global models surely does not capture the full picture of the Earth’s systems. As we move forward to attempt forecasting the Earth’s climate, it is also becoming essential to understand how the past climate behaved particularly at regional levels.
We have to do the science right and in the end, observations have to be better understood and statistical tests conducted. In this task, sustained global observations are paramount. If a enforceable ageement is signed in the future, the issue of monitoring will be immediately raised. For example, there are no direct ways for tracking GHG emissions at the plants themselves. Coordinated space observations will have to be brought in. Arguing about adhering to some value of global average temperatures will not be as important, in the end, as knowing quantitatively what the emissions are from each country.