To study the historical temperature variation in Yili of Xinjiang,the tree-ring chronologies of maximum density(MXD) and tree-ring width(TRW) were established with the Schrenk Spruce(Picea schrenkiana Fisch.et Mey) co...To study the historical temperature variation in Yili of Xinjiang,the tree-ring chronologies of maximum density(MXD) and tree-ring width(TRW) were established with the Schrenk Spruce(Picea schrenkiana Fisch.et Mey) collected from six sites to analyze the characteristics and ability of response to climate change.The results suggest that the MXD chronology of the Schrenk Spruce from different sampling sites responded to climate change well and were positively correlated with the mean maximum temperature and the mean temperature from April to August in the study area.The mean maximum temperature anomaly from April to August,spanning the years from 1848 to 2000,was reconstructed by three MXD chronologies which were selected by stepwise regression.The reconstructed function was stable and explained 56.2% of the variance.The reconstructed results indicated a cold span of 153 years in spring and summer from the beginning of the 1950s to the beginning of the 1970s in the Yili valley.No strongly increasing tendency was detected in the mean maximum temperature anomaly from April to August during this reconstructed period.展开更多
The climate is influenced by westerlies year in year out and the aeolian loess is widespread in the Yili region, the Xinjiang Uygur Autonomous Region. Through the study of the loess section with a thickness of 21.5 m,...The climate is influenced by westerlies year in year out and the aeolian loess is widespread in the Yili region, the Xinjiang Uygur Autonomous Region. Through the study of the loess section with a thickness of 21.5 m, much useful information about climatic change in this region during the last glaciation was gotten. Grain size analysis of loess samples in the section showed that the climatic change in the Yili region was of instability during the last glaciation and similar to those of the North Atlantic Ocean and Greenland. In correspondence with the Heinrich events, the percentage of the size fraction of loess with grain size less than 10 μm decreased in cold stadials in the Yili region. This result suggests that the westerly wind be strengthened during the cold periods. Compared with the stadials, the content of the loess with grain size less than 10 μm was increased in interstadials, which indicated that the strength of the westerly wind was weakened. It is obvious that the climate was instable展开更多
利用常规、地面加密观测资料,NCEP再分析资料(1°×1°),分析2012年11月29日—12月4日伊犁河谷持续性大暴雪成因。结果表明:(1)主导系统里黑海脊移速缓慢,西伯利亚深厚低涡主体西退,使得脊前低槽、强锋区不断与西退的冷空...利用常规、地面加密观测资料,NCEP再分析资料(1°×1°),分析2012年11月29日—12月4日伊犁河谷持续性大暴雪成因。结果表明:(1)主导系统里黑海脊移速缓慢,西伯利亚深厚低涡主体西退,使得脊前低槽、强锋区不断与西退的冷空气结合东移,高空偏西急流和低空偏西急流维持及加强东南移,提供有利天气背景。(2)水汽沿着地中海—里咸海—伊犁河谷接力输送至暴雪区,水汽辐合中心在850 h Pa附近。(3)大暴雪期间等θse线明显陡立,利于倾斜涡度发展。暴雪发生在MPV1等值线密集区和接近MPV2负值中心的区域。MPV2的较强发展触发垂直涡度增长,导致持续性强降雪发生。(4)受河谷特有地形影响,山前垂直环流的稳定维持和低空急流的加强为暴雪提供动力条件及不稳定能量的触发机制,增强降雪强度。展开更多
With the development of Internet technologies, Internet Based Information System (IBIS) arises with more advantages: Firstly, it is convenient for users to use owing to the introduction of Internet technologies. Secon...With the development of Internet technologies, Internet Based Information System (IBIS) arises with more advantages: Firstly, it is convenient for users to use owing to the introduction of Internet technologies. Secondly, it benefits greatly the data dissemination and data sharing based on Internet. The most important but not the last is that we can establish the information service network supported by its technologies and the facilities of information highway. So, it would be significant to design IBIS to realize the data collection, sharing and dissemination on Internet. There are many factors affecting regional environment. So it is not easy to realize the integrated environmental monitoring. Given this, we designed the Internet based environmental monitoring information system. By the virtue of the Internet based environmental monitoring information system, the management and storage of environmental monitoring data would be easier, which lays the foundation to actualize the environmental monitoring efficiently.展开更多
基金Supported by the National Basic Research Program of China (Grant No.2009CB421307)Research Foundation of Chinese Desert Meteorology (Grant No.SQJ2006013)National Natural Science Foundation of China (Grant Nos.30270227 and J0630965)
文摘To study the historical temperature variation in Yili of Xinjiang,the tree-ring chronologies of maximum density(MXD) and tree-ring width(TRW) were established with the Schrenk Spruce(Picea schrenkiana Fisch.et Mey) collected from six sites to analyze the characteristics and ability of response to climate change.The results suggest that the MXD chronology of the Schrenk Spruce from different sampling sites responded to climate change well and were positively correlated with the mean maximum temperature and the mean temperature from April to August in the study area.The mean maximum temperature anomaly from April to August,spanning the years from 1848 to 2000,was reconstructed by three MXD chronologies which were selected by stepwise regression.The reconstructed function was stable and explained 56.2% of the variance.The reconstructed results indicated a cold span of 153 years in spring and summer from the beginning of the 1950s to the beginning of the 1970s in the Yili valley.No strongly increasing tendency was detected in the mean maximum temperature anomaly from April to August during this reconstructed period.
文摘The climate is influenced by westerlies year in year out and the aeolian loess is widespread in the Yili region, the Xinjiang Uygur Autonomous Region. Through the study of the loess section with a thickness of 21.5 m, much useful information about climatic change in this region during the last glaciation was gotten. Grain size analysis of loess samples in the section showed that the climatic change in the Yili region was of instability during the last glaciation and similar to those of the North Atlantic Ocean and Greenland. In correspondence with the Heinrich events, the percentage of the size fraction of loess with grain size less than 10 μm decreased in cold stadials in the Yili region. This result suggests that the westerly wind be strengthened during the cold periods. Compared with the stadials, the content of the loess with grain size less than 10 μm was increased in interstadials, which indicated that the strength of the westerly wind was weakened. It is obvious that the climate was instable
文摘利用常规、地面加密观测资料,NCEP再分析资料(1°×1°),分析2012年11月29日—12月4日伊犁河谷持续性大暴雪成因。结果表明:(1)主导系统里黑海脊移速缓慢,西伯利亚深厚低涡主体西退,使得脊前低槽、强锋区不断与西退的冷空气结合东移,高空偏西急流和低空偏西急流维持及加强东南移,提供有利天气背景。(2)水汽沿着地中海—里咸海—伊犁河谷接力输送至暴雪区,水汽辐合中心在850 h Pa附近。(3)大暴雪期间等θse线明显陡立,利于倾斜涡度发展。暴雪发生在MPV1等值线密集区和接近MPV2负值中心的区域。MPV2的较强发展触发垂直涡度增长,导致持续性强降雪发生。(4)受河谷特有地形影响,山前垂直环流的稳定维持和低空急流的加强为暴雪提供动力条件及不稳定能量的触发机制,增强降雪强度。
基金Knowledge Innovation Project of CAS No. KZCX02-308
文摘With the development of Internet technologies, Internet Based Information System (IBIS) arises with more advantages: Firstly, it is convenient for users to use owing to the introduction of Internet technologies. Secondly, it benefits greatly the data dissemination and data sharing based on Internet. The most important but not the last is that we can establish the information service network supported by its technologies and the facilities of information highway. So, it would be significant to design IBIS to realize the data collection, sharing and dissemination on Internet. There are many factors affecting regional environment. So it is not easy to realize the integrated environmental monitoring. Given this, we designed the Internet based environmental monitoring information system. By the virtue of the Internet based environmental monitoring information system, the management and storage of environmental monitoring data would be easier, which lays the foundation to actualize the environmental monitoring efficiently.
