In reply to steepscotland: To be fair, THC shutdown is one of many theories in this field, and a fairly minor one at that. Obviously it would be a bit of a pig if it happened mind
Heinrich events are know to have happened in the past, but the huge complexity of of the global circulation makes modelling extremely hard, its nigh impossible to get models running that accurately just for the mediterranean FFS, and thats just one small part of the north atlantic system.