16:45 〜 17:00
[AOS09-12] Towards understanding climate extremes, variability and predictability under changing climate over East Asia
★Invited Papers
キーワード：異常気象、十年変動、地球温暖化
We aim at enhancing our understanding of climate extremes, variability and predictability under changing climate. In particular, we focus on decadal modulation of climate extremes over East Asia, mainly by preforming and analyzing comprehensive sets of climate simulations. Preliminary results underline that remote effects from the other oceans over the world will play important roles in modulating climate extremes such as heavy rainfall.
The Database for Policy Decision making for Future climate change (d4PDF) is composed of large ensembles of highly-resolved simulations using the atmospheric model and prescribed sea surface temperature (SST). We find that the interannual fluctuation of the chance of the heavy rainfall around the western Japan (over Kyushu island) is closely related to the tropical Pacific SST during 1981-2010. In addition, a close examination indicates decadal modulation in the relationship. The interannual fluctuations of the summertime heavy rainfall before 2000 and after 2000 are highly correlated with the Nino3 SST and the Nino West SST, respectively. The decadal modulation can be related to changes of the spatial patterns of the decadal SST anomalies predominantly observed in the tropical Pacific, on which our sensitivity experiments demonstrate the potential impacts of the Atlantic decadal variability. On the other hand, our analyses also indicate that the global warming worked to enhance the chance of the heavy rainfall particularly that is not accompanied by the tropical cyclone.
Other numerical studies suggest that other areas can also contribute to modulating the climate extremes in the East Asia. The so-called Silk Road Pattern which controls the remote influences from the extratropical Atlantic will be weakened with global warming. The recent sea ice loss over the Arctic area will work to enhance the chance of cold winter in the East Asia.
The Database for Policy Decision making for Future climate change (d4PDF) is composed of large ensembles of highly-resolved simulations using the atmospheric model and prescribed sea surface temperature (SST). We find that the interannual fluctuation of the chance of the heavy rainfall around the western Japan (over Kyushu island) is closely related to the tropical Pacific SST during 1981-2010. In addition, a close examination indicates decadal modulation in the relationship. The interannual fluctuations of the summertime heavy rainfall before 2000 and after 2000 are highly correlated with the Nino3 SST and the Nino West SST, respectively. The decadal modulation can be related to changes of the spatial patterns of the decadal SST anomalies predominantly observed in the tropical Pacific, on which our sensitivity experiments demonstrate the potential impacts of the Atlantic decadal variability. On the other hand, our analyses also indicate that the global warming worked to enhance the chance of the heavy rainfall particularly that is not accompanied by the tropical cyclone.
Other numerical studies suggest that other areas can also contribute to modulating the climate extremes in the East Asia. The so-called Silk Road Pattern which controls the remote influences from the extratropical Atlantic will be weakened with global warming. The recent sea ice loss over the Arctic area will work to enhance the chance of cold winter in the East Asia.