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Spatial distributions and interannual variations of snow cover over China in the last 40 years 被引量:8
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作者 ChengHai wang zhilan wang Yang Cui 《Research in Cold and Arid Regions》 2009年第6期509-518,共10页
By using the observational snow data of more than 700 weather stations,the interannual temporal and spatial characteristics of seasonal snow cover in China were analyzed.The results show that northern Xinjiang,northea... By using the observational snow data of more than 700 weather stations,the interannual temporal and spatial characteristics of seasonal snow cover in China were analyzed.The results show that northern Xinjiang,northeastern China–Inner Mongolia,and the southwestern and southern portions of Tibetan Plateau are three regions in China with high seasonal snow cover and also an interannual anomaly of snow cover.According to the trend of both the snow depth and snow cover days,there are three changing patterns for the seasonal snow cover:The first type is that both snow depth and snow cover days simultaneously increase or decrease;this includes northern Xinjiang,middle and eastern Inner Mongolia,and so on.The second is that snow depth increases but snow cover days decrease;this type mainly locates in the eastern parts of the northeastern plain of China and the upper reaches of the Yangtze River.The last type is that snow depth decreases but snow cover days increase at the same time such as that in middle parts of Tibetan Plateau.Snow cover in China appears to have been having a slow increasing trend during the last 40 years.On the decadal scale,snow depth and snow cover days slightly increased in the 1960s and then decreased in the 1970s;they again turn to increasing in the 1980s and persist into 1990s. 展开更多
关键词 snow cover snow depth and snow cover days spatial-temporal characters interannual and decadal variation
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Causes and Changes of Drought in China:Research Progress and Prospects 被引量:8
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作者 Qiang ZHANG Yubi YAO +6 位作者 Yaohui LI Jianping HUANG Zhuguo MA zhilan wang Suping wang Ying wang Yu ZHANG 《Journal of Meteorological Research》 SCIE CSCD 2020年第3期460-481,共22页
Drought is one of the most serious and extensive natural hazards in the world.Subject to monsoon climate variability,China is particularly influenced by drought hazards,especially meteorological drought.Based on a com... Drought is one of the most serious and extensive natural hazards in the world.Subject to monsoon climate variability,China is particularly influenced by drought hazards,especially meteorological drought.Based on a comprehensive understanding of the current status of international drought research,this paper systematically reviews the history and achievements of drought research in China since the founding of the People’s Republic of China,from four main perspectives:characteristics and spatiotemporal distribution of historical and recent drought events,drought formation mechanism and change trend,drought hazard risk,and the particular flash drought.The progress and problems of drought research in China are analyzed and future prospects are proposed,with emphasis on the multi-factor synergetic effect for drought formation;the effect of land-atmosphere interaction;identification,monitoring,and prediction of flash drought;categorization of drought and characteristics among various types of drought;the agricultural drought development;drought response to climate warming;and assessment of drought hazard risks.It is suggested that strengthening scientific experimental research on drought in China is imperative.The present review is conducive to strategic planning of drought research and application,and may facilitate further development of drought research in China. 展开更多
关键词 DROUGHT meteorological drought formation mechanism change trend drought hazard risk flash drought
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Generating series of intersection numbers on Hilbert schemes of points
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作者 zhilan wang Jian ZHOU 《Frontiers of Mathematics in China》 SCIE CSCD 2017年第5期1247-1264,共18页
我们包括重复的捆,和 _<sub> y </sub> TS <sup>[n]</sup> 的 Euler 特征的二个 Chern 班的交叉数字在表面 S <sup>[n]</sup>, 上在点的 Hilbert 计划上计算与重复的捆有关的积分的某产生系列。... 我们包括重复的捆,和 _<sub> y </sub> TS <sup>[n]</sup> 的 Euler 特征的二个 Chern 班的交叉数字在表面 S <sup>[n]</sup>, 上在点的 Hilbert 计划上计算与重复的捆有关的积分的某产生系列。我们也建议联系的一些推测,包括 Lehns 的一个 equivariant 版本推测。 展开更多
关键词 希尔伯特 相交数 级数 点集 交叉数 生成系 猜想 积分
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