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91.
ENSO冷暖事件与郑州地区汛期气候异常关系 总被引:1,自引:0,他引:1
利用1951—2000年郑州站汛期气温和降水资料,分析了ENSO冷暖事件与郑州地区汛期气候异常的关系。结果发现:ENS0冷暖事件对郑州地区汛期降水和气温均有较大影响,对降水异常的影响更显著。暖事件出现当年,郑州地区汛期易出现降水异常偏少,次年则易出现降水异常偏多;冷事件出现当年,郑州地区汛期降水易出现异常偏多,次年降水出现异常的几率较小。 相似文献
92.
There continues to be reluctance in some jurisdictions to use chemical dispersants as a viable countermeasure for accidental oil spills. One argument used by some opponents to dispersant use is that “chemical dispersants do not work effectively in cold water”. To address this issue, the U.S. Minerals Management Service (MMS) funded and conducted two series of large-scale dispersant experiments in very cold water at Ohmsett - The National Oil Spill Response Test Facility, located in Leonardo, New Jersey in February-March 2006 and January-March 2007. Alaska North Slope, Endicott, Northstar and Pt. McIntyre crude oils and Corexit 9500 and Corexit 9527 dispersants were used in the two test series. The crude oils were tested both when fresh and after weathering. Results demonstrated that both Corexit 9500 and Corexit 9527 dispersants were 85-99% effective in dispersing the fresh and weathered crude oils tested at cold temperatures. The MMS expects that results from these test series will assist government regulators and responders in making science based decisions on the use of dispersants as a response tool for oil spills in the Arctic. 相似文献
93.
We use the hydrographic data obtained during the joint survey of the Yellow Sea by the First Institute of Oceanography, China and the Korea Ocean Research and Development Institute, Korea, to quantify the spatial structures and temporal evolution of the southern Yellow Sea Cold Water Mass (YSCWM). It is indicated that the southern YSCWM is a water mass that develops in summer and decays in fall. In winter, due to the intrusion of the Yellow Sea Warm Current (YSWC), the central area (approximately between 34°N and 35°N, 122°E and 124°E) of the Yellow Sea is mainly occupied by relatively high temperature water (T>10 °C). By contrast, from early summer to fall, under the seasonal thermocline, the central area of Yellow Sea is occupied by cold water (T<10 °C). In summer, the southern YSCWM has two cold cores. One is formed locally southeast of Shandong Peninsula, and the other one has a tongue-like feature occupying the area approximately between 34°N and 37°N, 123°E and 126°E. The bottom layer temperature anomalies from February to July in the cold tongue region, along with the trajectories of the bottom floaters, suggest that the cold water mass in the northeast region has a displacement from the north to the central area of the Yellow Sea during the summer. 相似文献
94.
95.
This work offers a methodology based on statistical tools and GIS applications in a study of the adaptability of Opuntia to the environment, applied on the Mediterranean island of Sardinia. Detailed surveys of habitats containing naturalized populations of Opuntia spp. were made in order to select study sites. The topographic, soil and climatic features of these are described. The local biotypes are ascribed mainly to the spineless Opuntia ficus–indica (L.) Mill. and to the spiny Opuntia amyclaea Ten. Although introduced at different times, for different uses, they have adapted to the Sardinian environment and established in the wild. The distributions of the two species differed. The FloraMap® modelling approach was used to simulate Opuntia distribution as a function of the island's climate and produced individual distribution maps using the accession points for the two species. Our analysis showed that environmental conditions at elevations above 800 m are the main limiting factors for the presence and abundance of Opuntia in Sardinia. Spatial representation developed by GIS software indicated temperatures below 2 °C as the threshold impairing the species naturalized distribution. The statistic results also show that variation in rainfall does not affect Opuntia spatial distribution in Sardinia. 相似文献
96.
殷少有 《广东海洋大学学报》1999,(2)
推导了冷却物冷藏间内湿空气热物理参数计算方程,并编制了湿空气热物理参数计算程序。该程序能快速、精确地计算冷却物冷藏间内不同气流速度、不同气压的湿气热物理参数 相似文献
97.
中蒙强、弱沙尘暴年春季平均环流及沙尘活动变化分析 总被引:5,自引:3,他引:2
利用NCEP/NCAR再分析资料,对比分析了中蒙东、中及西区强、弱沙尘暴年春季(3—5月)平均环流的特征和差异,讨论了过去50年3分区沙尘暴活动的变化。主要结论是:(1)根据诱发沙尘暴的诱生系统、沙尘源地、冷空气入侵路径及主要影响,中蒙沙尘暴活动区可以划分为中蒙东区、中区及西区3个区系,并分区整体讨论与预测中蒙3分区的沙尘活动。(2)中蒙东区沙尘暴强年春季盛行日本海或中国东北低压活动,常随偏东的北路及东北路冷空气入侵,带来蒙古国东部的沙尘,造成蒙古东部及中国华北的沙尘天气;而弱年春季日本海及东北低压活动则少。(3)中蒙中区沙尘暴强年春季盛行蒙古低压,多西北路及偏西的北路冷空气入侵,常造成中蒙南边界西段附近的沙尘暴天气;而沙尘暴弱年春季则相反。(4)中蒙西区沙尘暴强年春季盛行南疆热低压,多西路冷空气入侵,诱发沙尘暴,常影响南疆及柴达木盆地等;弱年春季则相反。(5)近50年中蒙地区的沙尘暴活动呈波动变化,荒漠化环境、特别是大气环流的变化是导致上述3个分区沙尘活动波动变化的主要原因。主要从大气环流角度考虑,在目前全球增暖持续的背景下,近1—2年应注意中、东区(特别是东区)沙尘活动加强的可能性。 相似文献
98.
周定文 《成都信息工程学院学报》1990,(4)
本文将冷岛视为一个负的扰动加热源,即冷源,用小扰动方法求出了冷岛效应的分析解,给出了解例,并与热岛效应的结果作了对比分析。 相似文献
99.
利用国家气象信息中心提供的1951~2004年全国160个测站月平均降水资料和欧洲中心提供的ERA-40再分析资料,对近50多年东北地区夏季降水、东北冷涡与前期北半球环状模和海温的关系进行了统计分析,定义了一个夏季(6~8月)东北冷涡强度指数(NECVI)。结果表明:NECVI能够较好表征东北低涡的气候效应;夏季东北冷涡强度与降水存在显著的正相关,东北冷涡强年,降水偏多,前期2月北半球环状模(NAM)偏弱;东北冷涡偏弱年,降水偏少,前期2月NAM偏强。此外,夏季东北冷涡与前期的中国近海海温存在显著的负相关,前期NAM和中国近海海温的异常可以作为夏季东北冷涡异常的一个前兆信号,进而为东北地区夏季降水异常的预测提供参考依据。 相似文献
100.