We wish to acknowledge the support of the National Science Foundation, the Department of Energy, and the National Oceans and Atmosphere Administration which have generously supported this work through numerous grants, in particular NSF RII-8922105 ``EPSCOR Abrupt Climate Change,'' which provided the hardware on which much of this work was performed, DOE BR-7112-A-E ``Global Ice Sheet Modeling Project,'' and NOAA NA89AA-D-AC220, ``Future Sea Level Change''.