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31.
综合气象观测系统的发展 总被引：9，自引：0，他引：9
回顾了气象探测发展史,分析了气象探测与气象预报、气象科学发展之间的紧密关系,指出了气象探测的发展推动了气象科学、气象预报和气象服务的发展;进一步描述了气象探测发展的现状,对于新技术的应用前景与气象仪器的未来发展趋势进行了分析与阐述,同时介绍了国际GCOS、GEOSS、WIGOS综合观测计划. 相似文献
32.
近百年中国气候变暖趋势之再评估 总被引：5，自引：0，他引：5
基于均一化的气温观测序列集,1900年以来中国气温升高趋势1.3—1.7℃/（100 a）。这个已用于新近的中国国家气候变化评估报告的结果,远高于早期的评估结果（0.5—0.8℃/（100 a））。回顾了始于20世纪80年代的中国百年气温序列的研究,指出其中关键进展在于近年来研发了均一化的长期站点气温观测序列集。早年构建的中国气温序列中,20世纪40年代前异常偏高,除了战乱期间观测缺失严重及记录代表性问题外,主要是50年代前后很多台站迁址导致早期气温观测值系统性偏高所致,从而低估长期变暖趋势。40年代前后部分区域确实偏暖,但由于不同区域气温波动位相不一致,因而大范围平均序列中并不明显。这一事实可与近年发展的“北极暖-大陆冷”等气候变化动力学理论以及一些区域气温代用资料相印证。近几十年城市化对中国气温变化趋势之贡献大小尚存争议,但远非主导因素。 相似文献
33.
Yongjian Ren Lianchun Song Zunya Wang Ying Xiao Bing Zhou 《Acta Meteorologica Sinica》2017,31(2):397-408
Historical studies have shown that summer rainfall in eastern China undergoes decadal variations, with three apparent changes in the late 1970s, 1992, and the late 1990s. The present observational study indicates that summer precipitation over eastern China likely underwent a change in the late 2000s, during which the main spatial pattern changed from negative–positive–negative to positive–negative in the meridional direction. This change in summer precipitation over eastern China may have been associated with circulation anomalies in the middle/upper troposphere. A strong trough over Lake Baikal created a southward flow of cold air during 2009–15, compared with 1999–2008, while the westward recession of the western Pacific subtropical high strengthened the moisture transport to the north, creating conditions that were conducive for more rainfall in the north during this period. The phase shift of the Pacific Decadal Oscillation in the late 2000s led to the Pacific–Japan-type teleconnection wave train shifting from negative to positive phases, resulting in varied summer precipitation over eastern China. 相似文献
34.
全球气候安全问题已经日益突显,为了开展气候安全风险管理,国内学术界最近提出了气候容量的概念。然而,目前对气候容量的科学认识十分有限,甚至还没有比较统一的科学定义,对如何通过气候容量评价开展气候安全风险管理也没有明确的技术思路。在归纳总结以往研究的基础上,进一步讨论了气候容量及其对气候安全风险管理的作用,对气候容量给出了更加科学的定义和合理的诠释,并且分析了气候容量的科学属性和基本特征,探讨了全球气候安全风险的总体趋势,提出了利用气候容量的杠杆作用提升气候安全风险管理和气候资源开发利用水平的初步思路。这对推进我国气候业务对国家非传统安全的服务能力具有科学参考作用。 相似文献
35.
Changes in Seasonal Patterns of Temperature and Precipitation in China During 1971-2000 总被引：1，自引：0，他引：1
Many studies have shown evidence for significant changes in surface climate in different regions of the world and during different seasons over the past 100 years. Based on daily temperature and precipitation data from 720 climate stations in China, cluster analysis was used to identify regions in China that have experienced similar changes in the seasonal cycle of temperature and precipitation during the 1971-2000 climate normal period. Differences in 11-day averages of daily mean temperature and total precipitation between the first （1971-1985） and second （1986-2000） halves of the record were analyzed using the Mann- Whitney U test and the global κ-means clustering algorithm. Results show that most parts of China experienced significant increases in temperature between the two periods, especially in winter, although some of this warming may be attributable to the urban heat island effect in large cities. Most of western China experienced more precipitation in 1986-2000, while precipitation decreased in the Yellow River valley. Changes in the summer monsoon were also evident, with decreases in precipitation during the onset and decay phases, and increases during the wettest period. 相似文献
36.
绿洲周边荒漠戈壁夏末土壤-大气水分传输特征 总被引：10，自引：0，他引：10
利用“我国西北干旱区陆-气相互作用试验”2000年8-9月在甘肃敦煌地区戈壁滩上取得的野外观测资料,分析了临近绿洲的戈壁土壤湿度和温度特征以及相对应的大气湿度特征,发现土壤热量活动层约为5cm厚,比一般土壤要薄得多;临近绿洲的荒漠戈壁上,不仅近地层大气多为逆湿,而且浅层土壤有时也出现逆湿。土壤湿度日变化能清楚地被区分为湿维持、水分损失、干维持和水分补充等四个阶段。土壤湿度廓线表明：土壤水分活动层厚度约为10m;湿维持阶段的浅层土壤逆湿是土壤湿度廓线最主要的结构特征,这一土壤湿度结构预示着夜间土壤可能通过凝结吸收大气水分,它与白天的土壤水分蒸发共同构成土壤对大气水分的“呼吸”过程。土壤逆湿的形成与土壤温度状态、大气逆湿强度和大气稳定度都有关。 相似文献