Located in a monsoon domain,East Asia suffers devastating natural hazards induced by anomalous monsoon behaviors.East Asian monsoon(EAM)research has traditionally been a high priority for the Chinese climate community...Located in a monsoon domain,East Asia suffers devastating natural hazards induced by anomalous monsoon behaviors.East Asian monsoon(EAM)research has traditionally been a high priority for the Chinese climate community and is particularly challenging in a changing climate where the global mean temperature has been rising.Recent advances in studies of the variabilities and mechanisms of the EAM are reviewed in this paper,focusing on the interannual to interdecadal time scales.Some new results have been achieved in understanding the behaviors of the EAM,such as the evolution of the East Asian summer monsoon(EASM),including both its onset and withdrawal over the South China Sea,the changes in the northern boundary activity of the EASM,or the transitional climate zone in East Asia,and the cycle of the EASM and the East Asian winter monsoon and their linkages.In addition,understanding of the mechanism of the EAM variability has improved in several aspects,including the impacts of different types of ENSO on the EAM,the impacts from the Indian Ocean and Atlantic Ocean,and the roles of mid-to high-latitude processes.Finally,some scientific issues regarding our understanding of the EAM are proposed for future investigation.展开更多
A record-breaking extreme Meiyu rainfall occurred along the Yangtze River valley(YRV)in 2020 since 1961,persisting from 11 June to 31 July with the largest amount and the highest intensity.From the aspect of water vap...A record-breaking extreme Meiyu rainfall occurred along the Yangtze River valley(YRV)in 2020 since 1961,persisting from 11 June to 31 July with the largest amount and the highest intensity.From the aspect of water vapor,the causes of its formation are revealed in this study.The 2020 Meiyu rainfall amount is directly attributed to the greatly enhanced vertically integrated water vapor transport(IVT)convergence,which is in turn primarily determined by the mean circulation dynamic(MCD)contribution associated with anomalous East Asian summer monsoon(EASM)and the thermodynamic component(TH)contribution due to water vapor anomaly.The MCD contribution is mainly responsible for the extreme Meiyu rainfall amount and abundant water vapor convergence in the YRV,whereas the TH contribution tends to shift Meiyu rain belt northward to the Yangtze-Huaihe River valley,extending the Meiyu rainfall coverage area.Furthermore,the excessive moist static energy(MSE)associated with the largest water vapor anomaly could substantially increase the atmospheric instability,favoring the extreme 2020 Meiyu rainfall intensity.In terms of the tremendous IVT to the YRV from both the South China Sea and Bay of Bengal during the 2020 Meiyu period,the low-level anticyclone anomalies over the western North Pacific(WNP)and Bay of Bengal provide appropriate atmospheric circulation conditions,and they are generated by the super suppressed WNP convective activities as a Matsuno-Gill type response,which are further attributed to the combined warm SST anomalies in both the tropical western Indian Ocean(TWIO)and tropical Atlantic Ocean(TAO)eventually.展开更多
This work presents an overall introduction to the Station for Observing Regional Processes of the EarthSystem - SORPES in Nanjing, East China, and gives an overview about main scientific findings instudies of air poll...This work presents an overall introduction to the Station for Observing Regional Processes of the EarthSystem - SORPES in Nanjing, East China, and gives an overview about main scientific findings instudies of air pollution-weather/climate interactions obtained since 2011. The main results summarizedin this paper include overall characteristics of trace gases and aerosols, chemical transformationmechanisms for secondary pollutants like O3, HONO andsecondary ingrganic aerosols, and the airpollution- weather/climate interactions and feedbacks in mixed air pollution plumes from sources likefossil fuel combustion, biomass burning and dust storms. The future outlook of the development plan on instrumentation, networking and data-sharing for the SORPES station is also discussed.展开更多
基金supported jointly by the National Key Research and Development Program(Grant No.2016YFA0600604)the National Natural Science Foundation of China(Grant No.41721004)+1 种基金the Chinese Academy of Sciences Key Research Program of Frontier Sciences(Grant No.QYZDY-SSW-DQC024)the Jiangsu Collaborative Innovation Center for Climate Change
文摘Located in a monsoon domain,East Asia suffers devastating natural hazards induced by anomalous monsoon behaviors.East Asian monsoon(EAM)research has traditionally been a high priority for the Chinese climate community and is particularly challenging in a changing climate where the global mean temperature has been rising.Recent advances in studies of the variabilities and mechanisms of the EAM are reviewed in this paper,focusing on the interannual to interdecadal time scales.Some new results have been achieved in understanding the behaviors of the EAM,such as the evolution of the East Asian summer monsoon(EASM),including both its onset and withdrawal over the South China Sea,the changes in the northern boundary activity of the EASM,or the transitional climate zone in East Asia,and the cycle of the EASM and the East Asian winter monsoon and their linkages.In addition,understanding of the mechanism of the EAM variability has improved in several aspects,including the impacts of different types of ENSO on the EAM,the impacts from the Indian Ocean and Atlantic Ocean,and the roles of mid-to high-latitude processes.Finally,some scientific issues regarding our understanding of the EAM are proposed for future investigation.
基金Supported by the National Key Research and Development Program of China(2018YFC1505803)National Natural Science Foundation of China(41775074)Foundation for Innovative Research Groups of the National Natural Science Foundation of China(41621005)。
文摘A record-breaking extreme Meiyu rainfall occurred along the Yangtze River valley(YRV)in 2020 since 1961,persisting from 11 June to 31 July with the largest amount and the highest intensity.From the aspect of water vapor,the causes of its formation are revealed in this study.The 2020 Meiyu rainfall amount is directly attributed to the greatly enhanced vertically integrated water vapor transport(IVT)convergence,which is in turn primarily determined by the mean circulation dynamic(MCD)contribution associated with anomalous East Asian summer monsoon(EASM)and the thermodynamic component(TH)contribution due to water vapor anomaly.The MCD contribution is mainly responsible for the extreme Meiyu rainfall amount and abundant water vapor convergence in the YRV,whereas the TH contribution tends to shift Meiyu rain belt northward to the Yangtze-Huaihe River valley,extending the Meiyu rainfall coverage area.Furthermore,the excessive moist static energy(MSE)associated with the largest water vapor anomaly could substantially increase the atmospheric instability,favoring the extreme 2020 Meiyu rainfall intensity.In terms of the tremendous IVT to the YRV from both the South China Sea and Bay of Bengal during the 2020 Meiyu period,the low-level anticyclone anomalies over the western North Pacific(WNP)and Bay of Bengal provide appropriate atmospheric circulation conditions,and they are generated by the super suppressed WNP convective activities as a Matsuno-Gill type response,which are further attributed to the combined warm SST anomalies in both the tropical western Indian Ocean(TWIO)and tropical Atlantic Ocean(TAO)eventually.
基金The work was supported by the National Natural Science Foundation of China （Grant Nos. D0512/91544231, D0512/ 41422504, and D0510/41505109）, National Key Research and Development Program in China （No. 2016YFC0200506）, and Jiangsu Provincial Science Fund （No. BK20140021）. We thank L.F. Zheng, Z.N. Xu, L.S. Jin, E. Herrmann, Y.N. Xie, X.M. Qi, A. Virkkula, Z. Peng, Y.C. Shen, J.P. Wang, H. Shi, L. Wang, C.J. Zhu and H. Shi for their contributions on instrumental maintenance and field campaigns.
文摘This work presents an overall introduction to the Station for Observing Regional Processes of the EarthSystem - SORPES in Nanjing, East China, and gives an overview about main scientific findings instudies of air pollution-weather/climate interactions obtained since 2011. The main results summarizedin this paper include overall characteristics of trace gases and aerosols, chemical transformationmechanisms for secondary pollutants like O3, HONO andsecondary ingrganic aerosols, and the airpollution- weather/climate interactions and feedbacks in mixed air pollution plumes from sources likefossil fuel combustion, biomass burning and dust storms. The future outlook of the development plan on instrumentation, networking and data-sharing for the SORPES station is also discussed.
