4:15 PM - 4:45 PM
★ [PEM07-01] Impact of stratospheric ozone on paleoclimate reconstruction: Mid-Holocene experiment by using MRI Earth System Model
Keywords:ozone, solar radiation, paleoclimate, earth system model, sea ice
Stratospheric warming in the Antractic spring due to the positive anomaly of ozone causes negative westerly anomaly of the polar night jet by the thermal wind balance, and the annular mode response brings westerly anomaly near the surface. The decrease of the surface westerly weakens the northward component of the Ekman transport in the ocean, suppresses the sea ice transport to lower latitudes, and produces the warming in the polar region.
The importance of chemical feedbacks is supported by a correction of cold bias of SST in the southern hemisphere which is commonly seen in results of CMIP5/PMIP3 models. The comparison between the time variation of the sea ice distribution and that of the stratosphere-troposphere coupling patterns show the importance of coupled chemistry process related to ozone in the reconstruction of mid-Holothese climate.