Session: Warm Climates (Mid-Holocene, Last interglacial, Deep-time, Pliocene)
Author: Yihua Luan / email@example.com / Institute of Atmospheric Physics (IAP)/Chinese Academy of Sciences (CAS)
Co-author: Yongqiang Yu, IAP/CAS;
We have analyzed the basic warming patterns among three typical periods - the mid-
Holocene (MH), Medieval Warm Period (MWP), and the twentieth century warming (20CW) - and carried out a comprehensive heat budget analysis using four experiments simulated by FGOALS-s2. And we found that the model simulates similar spatial warming patterns in all three warm periods, e.g. stronger warming appears in the high latitudes. However, changes in surface air temperature (SAT) over the tropical regions are different: a significant warming occurs in the 20CW and MWP but a significant cooling in the MH. The heat budget analysis suggested that SAT changes are mainly induced by the heat flux. We further investigate how the ENSO change induced by the different external forcing in the three warm periods and found that the ENSO amplitude decrease in the MH but increase in the MWP. FGOALS-s2 simulated positive skewness in three warm periods, but underestimate the simulation of ENSO asymmetry.