Sorry Marg, but I cannot let this statement about global warming go unchallenged. Yes the world has warmed up. Yes this is natural and was caused by changes in the sun. No CO2 had absolutley nothing to do with the rise in temperature. Now the sun is quieting down, and the world is getting colder. The experimental scientific evidence shows that, here in February 2008, the slope of the temperature/time graph is negative, i.e. the wortd is cooling down. This despite the fact that CO2 levels are rising at an unprecedented rate. Jim.