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An overview of dry-wet climate variability among monsoon-westerly regions and the monsoon northernmost marginal active zone in China 总被引：7，自引：2，他引：5
Climate in mainland China can be divided into the monsoon region in the southeast and
the westerly region in the northwest as well as the intercross zone, i.e., the monsoon northernmost
marginal active zone that is oriented from Southwest China to the upper Yellow River, North China,
and Northeast China. In the three regions, dry-wet climate changes are directly linked to the
interaction of the southerly monsoon flow on the east side of the Tibetan Plateau and the westerly
flow on the north side of the Plateau from the inter-annual to inter-decadal timescales. Some basic
features of climate variability in the three regions for the last half century and the historical
hundreds of years are reviewed in this paper.
In the last half century, an increasing trend of summer precipitation associated with the enhancing
westerly flow is found in the westerly region from Xinjiang to northern parts of North China and
Northeast China. On the other hand, an increasing trend of summer precipitation along the Yangtze
River and a decreasing trend of summer precipitation along the monsoon northernmost marginal active
zone are associated with the weakening monsoon flow in East Asia.
Historical documents are widely distributed in the monsoon region for hundreds of years and natural
climate proxies are constructed in the non-monsoon region, while two types of climate proxies can be
commonly found over the monsoon northernmost marginal active zone. In the monsoon region, dry-wet
variation centers are altered among North China, the lower Yangtze River, and South China from one
century to another. Dry or wet anomalies are firstly observed along the monsoon northernmost marginal
active zone and shifted southward or southeastward to the Yangtze River valley and South China in
about a 70-year timescale. Severe drought events are experienced along the monsoon northernmost
marginal active zone during the last 5 centuries. Inter-decadal dry-wet variations are depicted by
natural proxies for the last 4--5 centuries in several areas over the non-monsoon region.
Some questions, such as the impact of global warming on dry-wet regime changes in China, complex
interactions between the monsoon and westerly flows in Northeast China, and the integrated multi-proxy
analysis throughout all of China, are proposed. 相似文献
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通过对线性和非线性，判别一回归和门限一回归、插值、距离和相似等预报方法的对比，分析了各种方法的特点及各自的局限性，并就如何改进统计预报方法提出相关建议。 相似文献
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利用中国486个测站1960-2000年逐日气温观测资料，采用分层聚类和相似分析方法，对中国月、季、半年、年平均气温进行了区划，通过动态分析分层聚类过程中组内和组间平均相关系数的差异指标，为不同季节气温分析、预测研究找到适宜的分区方案。得到中国年平均气温分区为23个区；冬、夏半年均为22个区；春、夏、秋、冬季分别为24、28、26、28个区；1～12月分别为24、23、18、18、18、25、19、20、29、31、18、24个区。在全球变暖的气候背景下，各区域年、季气温在变化趋势、阶段异常、极端变化上均有明显的区域差异。 相似文献
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山西夏季气温异常特征分析 总被引：3，自引：0，他引：3
首先分析了山西夏季气温异常的时空变化特征,并利用NCEP再分析资料和北太平洋海温资料,探讨了影响山西夏季气温异常的同期、前期因子。结果表明:近46年来,山西夏季气温的变化趋势不显著,上升趋势仅为0.04℃/10a。夏季气温的年代际变化特征明显,20世纪60年代至70年代中期是偏暖期,70年代后期至80年代末则为偏冷期,90年代后期进入偏暖时期。夏季气温变化趋势区域差别较大,北部、中部是增暖趋势,南部的大部分地区则是变冷趋势。冷、暖夏年同期和前期的大气环流形势差异显著,极涡、高纬地区的阻高和副高是影响山西省夏季气温异常的关键系统。前期冬、春季的LaNina事件可作为山西夏季气温异常的前兆信号。 相似文献
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应用人工神经元网络建立临汾地区分级降水预报系统秦爱民，张临平，薛双青（临汾地区气象局０４１０００）１引言人工神经元网络就是试图以模拟人脑神经系统的组织方式构成新型的信息处理系统，其工作模式即类似于大脑的用并行分布模式取代符号定义的计算机模式。十几年来... 相似文献
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本文在客观分析我国地市级预报业务发展情况的前提下，在建立规模较大的历史天气图、地面要素、数值预报产品库的基础上，设计一套集多种预报方法于一体的天气预报技术流程。其中各子系统设计均考虑到资料库归并、方法多样、模式客观、补充灵活、为在新的预报流程下，实现由主观预报向客观预报转变和多方位释用数值预报产品提供了新的思路。 相似文献
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经验公式在最低气温预报中的应用戴有学，秦爱民（临汾地区气象局０４１０００）最低气温预报是日常气象要素预报中的重要项目之一。我们使用经验公式￣［１］制作了１９９１年～１９９３年最低气温预报方法，并用平均绝对误差对该方法进行评价，结果表明该方法预报最低气... 相似文献