Data on past climate warmth may lead to better model of warm future

Abstract

Weather bureaus around the world have accumulated daily historical records of atmospheric conditions for more than a century to help forecast meteorological conditions 3 to 5 days ahead. To gain insight into the impact of possible future climate warming and constrain predictive models for a warm future, climatologists are seeking paleoclimatologic and paleoceanographic records from recent intervals of the late Quaternary, when conditions were demonstrably warmer than today. Results of past research on Brunhes-age paleoclimate suggest that Marine Isotope Stage 11 (MIS 11), an interval between 420 and 360 ka, was the longest and warmest interglacial interval of the past 500 kyr (see the recent review by Howard [1997]). This interval was characterized by warmer seasurface temperatures in high latitudes, strong thermohaline circulation, unusual carbonate plankton blooms in high latitudes, higher than present sea level, coral reef expansion resulting in large accumulation of neritic carbonates, and overall poor pelagic carbonate preservation.