The Paris Agreement in 2015 proposed a target to limit global warming to less than 2℃ and pursue efforts to limit warming to less than 1.5℃. Since then, great effort has been devoted to exploring the impacts of the 1.5℃ and 2℃ warming scenarios. A recent work published in Earth’s Future by a team of researchers from the Institute of Atmospheric Physics at the Chinese Academy of Sciences (IAP/CAS) finds that the seasonal cycle of precipitation is likely to enhance at stabilized 1.5℃ and 2℃ warming scenarios.
"Based on the output data of the Community Earth System Model low-warming experiment, we conclude that the enhancement is mainly caused by the increase in water vapor," said CHEN Ziming, the first author of the study and a doctoral student from the IAP/CAS.
The intensity of seasonal cycle is defined as the difference in precipitation between wet and dry seasons, representing the contrast of precipitation within a year. The wet and dry seasons were usually fixed as June to August and December to February, respectively, in the Northern Hemisphere and vice versa in the Southern Hemisphere. Neither the spatial distinction nor the temporal shifts in the wet and dry seasons have previously been considered.
"In our study, the intensity of the seasonal cycle is represented by the difference between mean precipitation in the wet and dry seasons for different regions and for each year," said CHEN.
Read more at Institute of Atmospheric Physics, Chinese Academy of Sciences
Image: The schematic of the precipitation in the wet and dry seasons and the annual range with the additional 0.5℃ of warming. (Credit: Ziming Chen)