US Presidential Election Reflects Major Changes in US PoliticsAt present,there have been quite a few assessments on the historical significance of US Presidential Election2016 for political change in the United States...US Presidential Election Reflects Major Changes in US PoliticsAt present,there have been quite a few assessments on the historical significance of US Presidential Election2016 for political change in the United States,all of which be it high or low point to a new departure point or turning point in US politics.First,the Election reflects major changes in the power pattern展开更多
By using monthly NCEP/NCAR meridional gridpoint wind data at the levels of 1000, 850, 700, 600, 500, 400, 300, 200, 150 and 100 hPa from 1948 to 2004, the intensity of global cross-equatorial flows is calculated. The ...By using monthly NCEP/NCAR meridional gridpoint wind data at the levels of 1000, 850, 700, 600, 500, 400, 300, 200, 150 and 100 hPa from 1948 to 2004, the intensity of global cross-equatorial flows is calculated. The spatial and temporal variation of global cross-equatorial flows at the 850-hPa level are shown and discussed. The results show that the strength of the 850-hPa global cross-equatorial flows represent obvious long-term variation and interdecadal change during the period. Evidence suggests that the cross-equatorial flow of the passages at 45 - 50 °E in June to August, 105 - 115 °E in May to September, 130 - 140 °E in May to September and May to November and 20 - 25 °E in February to April intensified and that the cross-equatorial flow of the passages at 50 - 35 °W in June to August weaken in the past 57 years, with an increase of 0.25m/s/10a for summer Somali Jet and increase of 0.32 m/s/10a for cross- equatorial flow at 130 - 140 °E in May to September The results of Singular Spectrum Analysis (SSA) for the time series indicate that for the cross-equatorial flow at 850 hPa, the interdecadal and long-term trend changes are 35% - 45%, and the interarmual variation is no more than 30%, in variance contribution. The results also reveal that the interarmual variation of intensity of the summer cross-equatorial flows in the Pacific is significantly correlated with Southern Oscillation. With weak Southern Oscillation, strong crossequatorial flows in Pacific will happen, though the summer Somali Jet is only a little positively correlated with North Atlantic Oscillation (NAO).展开更多
[ Objective] The aim was to study temperature changes in Jinan in recent 30 years. [ Method] Using temperature from 1981 to 2010 in six national ground meteorological observation stations in Jinan, and based on linear...[ Objective] The aim was to study temperature changes in Jinan in recent 30 years. [ Method] Using temperature from 1981 to 2010 in six national ground meteorological observation stations in Jinan, and based on linear evaluation method, temperature changes in Jinan in recent 30 years were discussed. [ Result] The mean annual temperature, mean annual highest temperature and mean annual lowest temperature were rising in recent 30 years. Mean annual lowest temperature was increasing and its tendency rate was 0.502 ℃/10 a, followed by mean annual temperature whose tendency rate was 0.288℃/10 a. Mean annual highest temperature increased most slowly and its tendency rate was 0.144 ℃/10 a. The mean annual lowest temperature rose most significantly in Zhangqiu and its tendency rate was 1. 347℃/10 a. This indicated that the rising mean annual temperature in Jinan was due to the mean annual lowest temperature. The contribution of Zhangqiu City to the temperature changes in the entire Jinan was the largest. For single station, mean annual temperature, mean annual highest temperature and mean annual lowest temperature, temperature rising tendency was small and its contribution was the smallest. [ Conclusion] The study provided theoretical basis for the observation, diagnosis, evaluation and decision-making of climate changes in Jinan.展开更多
This study analyzed the temporal precipitation variations in the arid Central Asia (ACA) and their regional differences during 1930-2009 using monthly gridded precipitation from the Climatic Research Unit (CRU). O...This study analyzed the temporal precipitation variations in the arid Central Asia (ACA) and their regional differences during 1930-2009 using monthly gridded precipitation from the Climatic Research Unit (CRU). Our results showed that the annual precipitation in this westerly circulation dominated arid region is generally increasing during the past 80 years, with an apparent increasing trend (0.7 mm/10 a) in winter. The precipitation variations in ACA also differ regionally, which can be divided into five distinct subregions (Ⅰ West Kazakhstan region, Ⅱ East Kazakhstan region, ⅢCentral Asia Plains region, Ⅳ Kyrgyzstan region, and V Iran Plateau region). The annual precipitation falls fairly even on all seasons in the two northern subregions (regions Ⅰ and Ⅱ, approximately north of 45°N), whereas the annual precipitation is falling mainly on winter and spring (accounting for up to 80% of the annual total precipitation) in the three southern subregions. The annual precipitation is increasing on all subregions except the southwestern ACA (subregion Ⅴ) during the past 80 years. A significant increase in precipitation appeared in subregions Ⅰ and Ⅲ. The long-term trends in annual precipitation in all subregions are determined mainly by trends in winter precipitation. Additionally, the precipitation in ACA has significant interannual variations. The 2-3-year cycle is identified in all subregions, while the 5-6-year cycle is also found in the three southern subregions. Besides the inter-annual variations, there were 3-4 episodic precipitation variations in all subregions, with the latest episodic change that started in the mid- to late 1970s. The precipitations in most of the study regions are fast increasing since the late 1970s. Overall, the responses of ACA precipitation to global warming are complicated. The variations of westerly circulation are likely the major factors that influence the precipitation variations in the study region.展开更多
文摘US Presidential Election Reflects Major Changes in US PoliticsAt present,there have been quite a few assessments on the historical significance of US Presidential Election2016 for political change in the United States,all of which be it high or low point to a new departure point or turning point in US politics.First,the Election reflects major changes in the power pattern
基金Natural Science Foundation of China (40775060)Research Fund for Tropical and MarineMeteorology Key Open Laboratory on Tropical Monsoon, CMA
文摘By using monthly NCEP/NCAR meridional gridpoint wind data at the levels of 1000, 850, 700, 600, 500, 400, 300, 200, 150 and 100 hPa from 1948 to 2004, the intensity of global cross-equatorial flows is calculated. The spatial and temporal variation of global cross-equatorial flows at the 850-hPa level are shown and discussed. The results show that the strength of the 850-hPa global cross-equatorial flows represent obvious long-term variation and interdecadal change during the period. Evidence suggests that the cross-equatorial flow of the passages at 45 - 50 °E in June to August, 105 - 115 °E in May to September, 130 - 140 °E in May to September and May to November and 20 - 25 °E in February to April intensified and that the cross-equatorial flow of the passages at 50 - 35 °W in June to August weaken in the past 57 years, with an increase of 0.25m/s/10a for summer Somali Jet and increase of 0.32 m/s/10a for cross- equatorial flow at 130 - 140 °E in May to September The results of Singular Spectrum Analysis (SSA) for the time series indicate that for the cross-equatorial flow at 850 hPa, the interdecadal and long-term trend changes are 35% - 45%, and the interarmual variation is no more than 30%, in variance contribution. The results also reveal that the interarmual variation of intensity of the summer cross-equatorial flows in the Pacific is significantly correlated with Southern Oscillation. With weak Southern Oscillation, strong crossequatorial flows in Pacific will happen, though the summer Somali Jet is only a little positively correlated with North Atlantic Oscillation (NAO).
文摘[ Objective] The aim was to study temperature changes in Jinan in recent 30 years. [ Method] Using temperature from 1981 to 2010 in six national ground meteorological observation stations in Jinan, and based on linear evaluation method, temperature changes in Jinan in recent 30 years were discussed. [ Result] The mean annual temperature, mean annual highest temperature and mean annual lowest temperature were rising in recent 30 years. Mean annual lowest temperature was increasing and its tendency rate was 0.502 ℃/10 a, followed by mean annual temperature whose tendency rate was 0.288℃/10 a. Mean annual highest temperature increased most slowly and its tendency rate was 0.144 ℃/10 a. The mean annual lowest temperature rose most significantly in Zhangqiu and its tendency rate was 1. 347℃/10 a. This indicated that the rising mean annual temperature in Jinan was due to the mean annual lowest temperature. The contribution of Zhangqiu City to the temperature changes in the entire Jinan was the largest. For single station, mean annual temperature, mean annual highest temperature and mean annual lowest temperature, temperature rising tendency was small and its contribution was the smallest. [ Conclusion] The study provided theoretical basis for the observation, diagnosis, evaluation and decision-making of climate changes in Jinan.
基金supported by National Basic Research Program of China (Grant No. 2010CB950202)National Natural Science Foundation of China (Grant Nos. 40971056 and 41021091)Fundamental Research Funds for the Central Universities (Grant No. LZUJBKY-2009-82)
文摘This study analyzed the temporal precipitation variations in the arid Central Asia (ACA) and their regional differences during 1930-2009 using monthly gridded precipitation from the Climatic Research Unit (CRU). Our results showed that the annual precipitation in this westerly circulation dominated arid region is generally increasing during the past 80 years, with an apparent increasing trend (0.7 mm/10 a) in winter. The precipitation variations in ACA also differ regionally, which can be divided into five distinct subregions (Ⅰ West Kazakhstan region, Ⅱ East Kazakhstan region, ⅢCentral Asia Plains region, Ⅳ Kyrgyzstan region, and V Iran Plateau region). The annual precipitation falls fairly even on all seasons in the two northern subregions (regions Ⅰ and Ⅱ, approximately north of 45°N), whereas the annual precipitation is falling mainly on winter and spring (accounting for up to 80% of the annual total precipitation) in the three southern subregions. The annual precipitation is increasing on all subregions except the southwestern ACA (subregion Ⅴ) during the past 80 years. A significant increase in precipitation appeared in subregions Ⅰ and Ⅲ. The long-term trends in annual precipitation in all subregions are determined mainly by trends in winter precipitation. Additionally, the precipitation in ACA has significant interannual variations. The 2-3-year cycle is identified in all subregions, while the 5-6-year cycle is also found in the three southern subregions. Besides the inter-annual variations, there were 3-4 episodic precipitation variations in all subregions, with the latest episodic change that started in the mid- to late 1970s. The precipitations in most of the study regions are fast increasing since the late 1970s. Overall, the responses of ACA precipitation to global warming are complicated. The variations of westerly circulation are likely the major factors that influence the precipitation variations in the study region.