abrupt climate change in historical times

Tom Stafford was an expert among experts at the Fall Meeting.  I became aware of Tom Stafford when Redefining the Age of Clovis: Implications for the Peopling of America was published in Science in 2007.  He is the Former Director of the Laboratory of AMS Radicarbon Research at University of Colorado.  And for more than decade he has been President of Stafford Research Laboratories — the…