Based on daily maximum temperature data from Chinese weather stations for the period 1960- 2013, the characteristics of the interdecadal variability of large-scale extreme hot event （EHE） frequency over the middle a...Based on daily maximum temperature data from Chinese weather stations for the period 1960- 2013, the characteristics of the interdecadal variability of large-scale extreme hot event （EHE） frequency over the middle and lower reaches of the Yangtze River basin （MLYR） are analyzed. It is found that the frequency of large-scale EHE over the MLYR experiences two significant interdecadal changes, around the early 1970s and early 2000s, having a more-less-more variability shape during the past half century. Furthermore, the EHE frequency interdecadal variability-related atmospheric circulation patterns are diagnosed. The results indicate the western Pacific subtropical high could not be the dominant atmospheric circulation associated with the interdecadal variability of the large-scale EHE frequency over the MLYR. In contrast, the dominant teleconnection pattern over the Eurasian continent, which is represented by the second empirical orthogonal function mode of the 200 hPa geopotential height, is closely related to the interdecadal variability of the EHE frequency over the MLYR. The results of this study deepen our understanding of the variability of the EHE frequency over the MLYR and its possible mechanism.展开更多
This paper investigates the interdecadal variability in the lagged relationship between the spring Victoria mode(VM)and the following-winter El Ni?o–Southern Oscillation(ENSO).It is found that the relationship is str...This paper investigates the interdecadal variability in the lagged relationship between the spring Victoria mode(VM)and the following-winter El Ni?o–Southern Oscillation(ENSO).It is found that the relationship is strong during high correlation(HC)periods,e.g.1957–1964 and 1981–2004,but weak during low correlation(LC)periods,e.g.1907–1924,1926–1956,1965–1980,and2005–2008.The surface air–sea coupling and the evolution of subsurface ocean temperature anomaliesh along the equatorial Paci?c associated with the VM are found to be strong during HC periods and weak during LC periods,which results in a stronger impact of the VM on the following-winter ENSO during HC periods.The interdecadal change in the relationship between the VM and ENSO is mainly due to the interdecadal change in the intensity of the VM,which is found to be in?uenced by the North Paci?c Oscillation.Our?ndings may improve the prediction skill for the onset of ENSO events.展开更多
基金supported by the National Natural Science Foundation of China[grant number 41421004],[grant number41522503]the External Cooperation Program of the Bureau of International Co-operation,Chinese Academy of Sciences[grant number 134111KYSB20150016]
文摘Based on daily maximum temperature data from Chinese weather stations for the period 1960- 2013, the characteristics of the interdecadal variability of large-scale extreme hot event （EHE） frequency over the middle and lower reaches of the Yangtze River basin （MLYR） are analyzed. It is found that the frequency of large-scale EHE over the MLYR experiences two significant interdecadal changes, around the early 1970s and early 2000s, having a more-less-more variability shape during the past half century. Furthermore, the EHE frequency interdecadal variability-related atmospheric circulation patterns are diagnosed. The results indicate the western Pacific subtropical high could not be the dominant atmospheric circulation associated with the interdecadal variability of the large-scale EHE frequency over the MLYR. In contrast, the dominant teleconnection pattern over the Eurasian continent, which is represented by the second empirical orthogonal function mode of the 200 hPa geopotential height, is closely related to the interdecadal variability of the EHE frequency over the MLYR. The results of this study deepen our understanding of the variability of the EHE frequency over the MLYR and its possible mechanism.
基金supported by the National Natural Science Foundation of China [grant number 41790474]the National Program on Global Change and Air–Sea Interaction[grant numbers GASI-IPOVAI-06 and GASI-IPOVAI-03]the National Key Technology Research and Development Program of the Ministry of Science and Technology of China [grant number 2015BAC03B07]
文摘This paper investigates the interdecadal variability in the lagged relationship between the spring Victoria mode(VM)and the following-winter El Ni?o–Southern Oscillation(ENSO).It is found that the relationship is strong during high correlation(HC)periods,e.g.1957–1964 and 1981–2004,but weak during low correlation(LC)periods,e.g.1907–1924,1926–1956,1965–1980,and2005–2008.The surface air–sea coupling and the evolution of subsurface ocean temperature anomaliesh along the equatorial Paci?c associated with the VM are found to be strong during HC periods and weak during LC periods,which results in a stronger impact of the VM on the following-winter ENSO during HC periods.The interdecadal change in the relationship between the VM and ENSO is mainly due to the interdecadal change in the intensity of the VM,which is found to be in?uenced by the North Paci?c Oscillation.Our?ndings may improve the prediction skill for the onset of ENSO events.
