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191.
Bruce P. Hayden 《Journal of the American Water Resources Association》1999,35(6):1387-1397
ABSTRACT: Climate change due to enrichment of the atmosphere with carbon dioxide is projected to change the circulation of the atmosphere, increase its moisture content, warm the surface layers, and increase precipitation. Extratropical storms are the intermediate agent in mid-latitudes between changes in the circulation of the atmosphere and surface water resources. The climatology of extratropical storms for the period 1885–1996 is presented, and major changes in storminess are detected across much of North America. General Circulation Model (GCM) projections of storm frequency and storm track are found to have little in common with the observed pattern of storms and evidence no systematic changes in response to an enrichment of the atmosphere with carbon dioxide. 相似文献
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194.
Osamu Abe Wenshou Wei Masao Mikami Kenji Kosugi Junrong Xu Takeshi Sato Mingzhe Liu Masujiro Shimizu Atsushi Sato 《Water, Air, & Soil Pollution: Focus》2005,5(3-6):3-13
Four automatic weather stations (AWS) were installed on the slopes and foot areas of the Tianshan and Kunlun Mountains along
a longitude of 80 degrees east: (1) Taglak 2400 m a.s.l., (2) Aksu 1000 m, (3) Kartash 2800 m, and (4) Qira 1700 m. These
two slopes face the Taklimakan Desert. Tagliak lies on the southern slope of Tianshan, and Kartash on the northern slope of
Kunlun. The meteorological characteristics of the mountainous regions were investigated using surface data obtained during
an intensive observation period (IOP) in spring 2002. It was found that visibility on the slopes decreases in the daytime,
and there is no relationship between visibility and wind speed in the mountainous areas. Two snow layers containing dust particles
were observed in the snow cover in Taglak during the IOP in spring 2003. These results suggest that a warm air parcel containing
aeolian dust climbs over the slopes of the mountainous areas, and dust particles in the mountainous areas are transported
from the foot areas. 相似文献
195.
五羊-本田摩托(广州)有限公司生产基地有年产40万台发动机和摩托车外观件的生产车间,其中,机加工乳化液和涂装循环水是由污水处理站处理的,通过工艺流程的改造利用及加强制度管理,使处理站平衡高效运行,出水达到了广州市一级排放标准。 相似文献
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本文对北京等华北中部5站1956至1985年旱涝成因进行了分析讨论.结果表明,区域性旱涝主要是在海洋和局地土壤热状况异常作用下产生的.对华北中部而言,冬季黑潮海温与局地地温变化是引起汛期旱涝变异最重要的原因.前期下垫面热源异常对后期旱涝影响往往是通过累积的异常加热造成环流形势和系统的异常而实现的.海温与地温影响降水的机制不同,前者的影响是大尺度的,而后者的影响只是区域性的.当海温异常造成的大尺度环流变化与局地热状况都有利于降水时.洪涝更容易发生,反之易旱. 相似文献
199.
Richard A. Osgood Jonathan E. Stiegler 《Journal of the American Water Resources Association》1990,26(2):209-217
ABSTRACT: Crystal Lake, a small urban lake in Robbinsdale, MN, had been artificially circulated for 12 years before a detailed water quality evaluation was undertaken. In 1986, the circulation system was shut off for a two-year assessment. Although the lake remained hypereutrophic, the use of the lake, which included shoreline fishing and feeding ducks and geese, did not appear to be seriously impaired by the absence of artificial circulation. The circulation system was returned to service in October 1987 (there are 16 diffusers in this 0.31 km?2 lake). Continuous limnological data from October 1987 through October 1988, plus several sampling dates in 1989, compares to the two non-circulation years (1986 and 1987) as follows: there was a two- to three-fold increase in the lake's concentration of total phosphorus, total Kjeldahl nitrogen, and chlorophyll and a similar decrease in Secchi disk transparency. The surface oxygen concentration was reduced and the deep waters were nearly anoxic. In fact, following a wind storm in 1988, the entire lake became anoxic due to the mixing of high BOD throughout the water column, and a summertime fish-kill resulted. All of these occurrences are related to the artificial circulation of the lake. 相似文献
200.
简要回顾了潮汐河口环流、湍流、混合与层化的基本物理概念、内涵、研究方法、研究成果,指出了主要的研究进展,最后,展望了今后的研究方向。本文不考虑悬沙和风浪的影响。经典的河口环流也因潮汐应变的出现而受到挑战,河口环流由重力环流和潮汐应变环流构成。“涡黏度-剪切协方差(ESCO)”概念的提出,又区分出重力ESCO环流与潮汐ESCO环流。横向环流,尤其具有曲率的弯道中的横向环流,也得到进一步的理解。涡度方法的应用,揭示横向环流不仅由各种不同物理机制造成,而且对纵向河口重力环流有重要的影响。分层流中剪切湍流的理论加深了人们对潮汐河口湍流、混合的物理学的认识,势能差异方程更是使得定量理解潮汐河口混合与层化的三维时间、空间变化成为可能。 相似文献