Absolute age relationships between (a) size reduction of continental ice sheets, (b) glacio-eustatic sea level rise, (c) temperature changes of the ocean surface, and (d) temperature changes on land show that the proper sequence is as follows: first, withdrawal of the ice sheets; second, warming of the land surface; and, third, warming of the ocean surface. At about 13,000 years only one-half of the ice surface remained. Significant warming of the land surface began about 14,000 years ago, although several short cold phases occurred after that time. The sudden warming of the ocean surface did not take place until between 12.000 and 11,000 years ago.