I spoke about the Medieval Warm Period and the worldwide droughts that occurred between A.D. 800 and 1200, and, as I did in the book, then talked about the implications of the warming of a thousand years ago for our present era of warming. Much of the lecture was about droughts ancient and projected for the future, which resonated strongly with my audience. Catalonia, like the rest of Spain, is deeply concerned about aridity indeed the area is in the midst of a multiyear drought. They are talking of shipping in water, which cannot be a permanent solution to the water shortage problem. Apparently, the situation is compounded by large numbers of illegal wells, which are drawing down an already stressed water table. Much of the discussion at the all-day session was about changing social attitudes toward climate change and about infrastructure needs. I was struck at how little mention there was of drought and water, which indeed seems to be the "silent elephant in the climatic room" here and elsewhere.

I don't think that many in the audience had thought of archaeology as anything more than a way of discovering ancient civilizations and analyzing human evolution. It seemed to be a real eye opener to them that the study of the remote past has important lessons for the challenges we face with climatic change now and in the future. We archaeologists don't get involved in discussions about climate change nearly as much as we should. Indeed, I'm struck when I talk to paleoclimatologists just how few of them ever think about the impact of climate change on people in the past. Even archaeologists themselves have still done little to study climate as a factor in the major developments of the past. This is something that is still little studied, although this is changing as we become ever more concerned about global warming, and ever more fine-grained climatic information comes to hand. Much of the concern in the Catalonia conference was with self-sustainability, which is something which archaeologists think about a lot of the time--but the wider audience is unaware of this.

What's exciting is that I seem to be lecturing to more and more totally non-archaeological audiences. Almost invariably, they are very excited about the potential of archaeology for better understanding human responses to climate change. We still have a lot to learn about the past which is relevant to today and tomorrow--provided we get away from the Indiana Jones image that Hollywood has unwittingly, and entertainingly, pinned upon us.