Based on daily observation data in the Three Gorges Region(TGR)of the Yangtze River Basin and global reanalysis data,the authors analyzed the climate characteristics and associated temporal variations in the main mete...Based on daily observation data in the Three Gorges Region(TGR)of the Yangtze River Basin and global reanalysis data,the authors analyzed the climate characteristics and associated temporal variations in the main meteorological factors in 2021,as well as the year’s climatic events and meteorological disasters.The 2021 average temperature was 0.2℃above the 1991-2020 average and the 13 th-warmest year since 1961.Seasonally,winter and autumn were both warmer than usual.The annual mean precipitation was 12.8%above normal,and most regions experienced abundant rainfall throughout the year.The seasonal variation in precipitation was significant and the TGR had a wetter-than-normal spring and summer.The number of rainstorm days was higher than normal;the wind speed was above normal;and the relative humidity was higher than normal.In terms of rain acidity,2021 was tied with 2020 as the lowest since 1999.From mid-September to early October 2021,the TGR experienced exceptional high-temperature weather,which was driven by abnormal activity of mid-and high-latitude atmospheric circulation over the Eurasian continent and the western Pacific subtropical high(WPSH).In addition,a strong blocking high over the Ural Mountains accompanied by intense mid-latitude westerly winds prevented cyclonic disturbances from extending to the subtropical region.As a result,under the combined effect of the weaker-than-normal cold-air activities and the anomalous WPSH,the TGR experienced extreme high-temperature weather during early autumn 2021.展开更多
In this paper, 197 samples were gathered from a 820 cm profile in Donganchi of Fangshan, Beijing. They provided a continuous record of vegetation and environmental change overca.15,000 aB. P.. By these records, it is ...In this paper, 197 samples were gathered from a 820 cm profile in Donganchi of Fangshan, Beijing. They provided a continuous record of vegetation and environmental change overca.15,000 aB. P.. By these records, it is concluded that in about 14, 100~14, 000 aB. P, the climate was cold and dry, which corresponds to Gothenburg Drift and interval between 10, 620 to10, 310 aB. P.. The rapid decline in pollen, charcoal concentrations and LOI implied a more cold-er climate and probably corresponded to Younger Dryas cooling event, at 5, 770 aB. P., 4, 650aB. P. and 2, 850 ~ 2, 650 aB. P., while the decline of forest cover showed three abrupt coldepisodes.展开更多
The anomalies of precipitation and surface air temperature in the summer (June to August) of 1997 are simulated by use of a global spectral numerical climate model (L9R15) developed in Australia originally and modifie...The anomalies of precipitation and surface air temperature in the summer (June to August) of 1997 are simulated by use of a global spectral numerical climate model (L9R15) developed in Australia originally and modified in LASG. The purpose of this paper is to study the effect of the El Nino event that happened in that year on the anomalies. The results show that the 1997 El Nino event does have a lot of influences on the climatic anomaly in that summer, however, the effect is not the same as pointed out by statistical studies. Therefore, the effects of the El Nino events are of uncertainties. The effects of the El Nino events on the regional climate in China might be different due to the different SSTA distributions over the western and northwestern Pacific in the El Nino years. It is likely more important to pay attention to the SSTA distributive patterns and values in the Chinese adjacent oceans. Besides the El Nino event there might be other factors such as the South Asia high at the 100 hPa level which has more direct impact on the climatic anomaly in China and can be taken as another strong signal of the climatic change in the atmosphere. Key words Climatic anomalies - Numerical modelling - Effect of El Nino event Sponsored by the Key Program of National Natural Science Foundation of China: “ Analyses and Mechanism Study of the Regional Climatic Change in China” under Grant No. 49735170.展开更多
基金jointly supported by the funds of the Strategic Cooperation Agreement Project between the China Meteorological Administration and the Three Gorges Corporation[Grant No.0704182]the Comprehensive Monitoring Program for Operational Safety of the Three Gorges Project[Grant No.SK2021015]financed by the Ministry of Water Resources of China.
文摘Based on daily observation data in the Three Gorges Region(TGR)of the Yangtze River Basin and global reanalysis data,the authors analyzed the climate characteristics and associated temporal variations in the main meteorological factors in 2021,as well as the year’s climatic events and meteorological disasters.The 2021 average temperature was 0.2℃above the 1991-2020 average and the 13 th-warmest year since 1961.Seasonally,winter and autumn were both warmer than usual.The annual mean precipitation was 12.8%above normal,and most regions experienced abundant rainfall throughout the year.The seasonal variation in precipitation was significant and the TGR had a wetter-than-normal spring and summer.The number of rainstorm days was higher than normal;the wind speed was above normal;and the relative humidity was higher than normal.In terms of rain acidity,2021 was tied with 2020 as the lowest since 1999.From mid-September to early October 2021,the TGR experienced exceptional high-temperature weather,which was driven by abnormal activity of mid-and high-latitude atmospheric circulation over the Eurasian continent and the western Pacific subtropical high(WPSH).In addition,a strong blocking high over the Ural Mountains accompanied by intense mid-latitude westerly winds prevented cyclonic disturbances from extending to the subtropical region.As a result,under the combined effect of the weaker-than-normal cold-air activities and the anomalous WPSH,the TGR experienced extreme high-temperature weather during early autumn 2021.
文摘In this paper, 197 samples were gathered from a 820 cm profile in Donganchi of Fangshan, Beijing. They provided a continuous record of vegetation and environmental change overca.15,000 aB. P.. By these records, it is concluded that in about 14, 100~14, 000 aB. P, the climate was cold and dry, which corresponds to Gothenburg Drift and interval between 10, 620 to10, 310 aB. P.. The rapid decline in pollen, charcoal concentrations and LOI implied a more cold-er climate and probably corresponded to Younger Dryas cooling event, at 5, 770 aB. P., 4, 650aB. P. and 2, 850 ~ 2, 650 aB. P., while the decline of forest cover showed three abrupt coldepisodes.
基金the Key Program of National Natural Science Foundation of China: u Analyses Mechanism Study of the Regional Climatic Change
文摘The anomalies of precipitation and surface air temperature in the summer (June to August) of 1997 are simulated by use of a global spectral numerical climate model (L9R15) developed in Australia originally and modified in LASG. The purpose of this paper is to study the effect of the El Nino event that happened in that year on the anomalies. The results show that the 1997 El Nino event does have a lot of influences on the climatic anomaly in that summer, however, the effect is not the same as pointed out by statistical studies. Therefore, the effects of the El Nino events are of uncertainties. The effects of the El Nino events on the regional climate in China might be different due to the different SSTA distributions over the western and northwestern Pacific in the El Nino years. It is likely more important to pay attention to the SSTA distributive patterns and values in the Chinese adjacent oceans. Besides the El Nino event there might be other factors such as the South Asia high at the 100 hPa level which has more direct impact on the climatic anomaly in China and can be taken as another strong signal of the climatic change in the atmosphere. Key words Climatic anomalies - Numerical modelling - Effect of El Nino event Sponsored by the Key Program of National Natural Science Foundation of China: “ Analyses and Mechanism Study of the Regional Climatic Change in China” under Grant No. 49735170.
