Collaborative Research: Testing Earth System Models with Paleoenvironmental Observations (TEMPO)

Investigator: John E. Kutzbach jek@facstaff.wisc.edu  (Principal Investigator current)          Zhengyu Liu  (Co-Principal Investigator current)          Jonathan A. Foley  (Co-Principal Investigator current)

Abstract

This award  provides support for the development and testing of fully interactive earth-system models that allow for feedbacks among the  atmosphere, hydrosphere,  and biosphere. Paleoclimate studies have shown how feedbacks among earth system components play a key role in the large climate changes since the last glacial maximum (LGM) 21,000 years ago (21 ka). Newly established global paleoclimatic data sets and improved earth system models will allow TEMPO investigators to explore the impact of these feedbacks on the simulation of 21 and 6 ka climates and also on inducing abrupt changes in late-glacial and Holocene climates. The proponents plan to use a fast synchronously coupled atmosphere-ocean model with and without IBIS, a biosphere model, synchronously coupled to it and make both long (500-1000 yr) and short (50-~00 yr) integrations to test the impacts of ocean, biospheric, and hydrological feedbacks on the climate simulations. The research will focus on 1) simulations of the mean climates for 21 and 6 ka with global  data/model comparisons,  model/model  comparisons, and estimation of the decade-to-century-scale variability at these dates; 2) exploratory simulations of some possible causes of abrupt changes since 21 ka with thorough analysis and comparison with temporal sequences of vegetational and hydrological data; and 3) mean and transient simulations for 2x or 3xCO2 and comparisons with the mechanisms that produced the mean state, variability and abrupt changes during the last 21 ka. This latter research will link our studies of past climates directly to the study of possible future climates.