Perry’s take on global warming is exactly right. The science is not settled. We simply do not know the mechanism for climate change. Certainly the huge changes of the past 1000 years were not effected by human activity. Not 800 years ago, Southern California was a barren desert much like Nevada and there was no snow cover at all for the mountaiins. At the very same time, Europe was warmer than its is today. Then withoin a hundred years the climate in both places changed. The climate in S. California became cooler and wetter and that of Europe did also. The little ice age is wellknow to European hiustory. Then in the 18th century it began to warm again. It is well known that London today does not experience the winters that Dickens describes.