Just so you all know, I looked into it. The medieval warming period was caused by a change in a narrow band of air currents that affected the southwestern U.S. and hte North Atlantic. Ice cores and fossil records and so forth from other parts of the world show taht the warming was not worldwide. However, enough things melted quickly enough in the northern Atlantic to destabilize the ocean currents that moderate the climate in that region, and then the sun entered a relatively inactive period.
Earth's climate is seriously dynamically unstable, and it's extremely unwise to mess with it, in my opinion. It often takes a relatively minor event to tip the scales.
Yours, Dora Smith Austin, TX tiggernut24@yahoo.com
"But he agreed that two periods in recent times had experienced similar warming. And he agreed that the debate had not been settled over whether the Medieval Warm Period was warmer than the current period."http://news.bbc.co.uk/2/hi/science/nature/8511701.stm"Most likely predominantly man-made?" Debate not settled over whether the Medieval Warm Period was warmer than now?!Well Phil, that's not what we were being told by people like you even just up to a few months ago. S7. www.tv.yahoo.com.au/plus7