Global warming over the next 100 years could increase drought, fires and floods, a federal report says.
Critics call the findings flawed.
There is a growing scientific consensus that the world's climate is warming. Scientists continue, however, to disagree about how much of the change is caused by natural temperature fluctuations and how much by human activities. I have tried for several years to get the United States to respond, to do our part. We are the largest emitter of greenhouse gases in the world. From a policy point of view, what we know about California is pretty skimpy.