At last something I can speak on with some knowledge on. Climate has been rising - fast for the last 18,000 years or so. 18,000 years ago Walrus lived around San Francisco Bay. People came to North American at about that time although the evidence is sketchy and they likely came again later. We (human-kind) have not been of sufficient numbers or able polluting enough till this past century to make any difference in the climate. The current rise in temperatures is on an order of what was happening between about 20,000 and 7,000 years ago. Also temperatures have been higher and much lower than present in the past. Not to say that we are not causing an increase in global warming, as I believe we are, but I see studies and comments all the time that do not take the long view of climate change. We need to do something but lets be honest in our discussions and politics. And to comment on the last million years there have been a number of times when temperatures have been both higher and lower than present - perhaps five or more of each! Climate change is natural - but we're not helping and I pray we don't overload the system to our determent. Best, Chuck Charles & Barbara Powell American Dendrobatid Group http://www.frogday.org/ --- On Fri, 1/15/10, pbs-request@lists.ibiblio.org <pbs-request@lists.ibiblio.org> wrote: The data are irrefutable: The earth's atmosphere and oceans are warming at a rate much faster than the history of the last 1,000,000 years or so suggest they should be. The difference between 100,000 years ago and today is the presence and consequences of about 6 billion additional members of the species Homo sapiens.