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991.
本文运用数理统计方法,对感冒和流感发生的气象条件进行了统计分析。得出了成都地区引起感冒发生的主要外界条件是气象因素中的日降温,而流感的暴发和流行与气象因素的关系不密切的结论。  相似文献   
992.
针对国内气象部门的要求,本文就某一特定地域对地球低轨道卫星进行轨道计算,使得地面测点能维持在该区域较长时间.计算结果表明该轨道可以使得无线电掩星的地面测点维持在辐射半径为100km之内的区域达130天左右。这基本满足了利用GPS无线电掩星技术对局部地域大气进行监测研究的要求。  相似文献   
993.
The greatest one-day rain amounts recorded at individual stations in the country during the last 41-year period from 1940 onwards were examined for all observatories as well as State rain-gauge stations in an attempt to bring out up-to-date information on the greatest recorded point rainfall for the duration of one day. Outstanding one-day point rainfall amounts recorded prior to 1940 were also examined and have been included in this note along with their date and year of occurrence by way of comparison. A generalized chart has been prepared based on the percentage ratios of the greatest one-day rainfall to the mean annual rainfall of about 300 observatory stations distributed uniformly over the entire country. On the basis of Depth-Area-Duration (DAD) analyses of the most severe rainstorms which occurred over different plain areas of the country, it has been found that the 2 July, 1941, rainstorm gave the highest areal rain depths in the country for different areas. Comparison with similar areal rain depths of the tropical USA has shown that rain depths of the July, 1941, rainstorm were higher for all areas excepting the areas of 500 sq. miles (1295 sq. km) and 1000 sq. miles (2590 sq. km).  相似文献   
994.
Temporal variation in the absolute value of interdiurnal variability (AIDV) of January maximum temperatures is examined for the period 1945–1985 in the central United States (90°–105°W). AIDV indicates the magnitude of day-to-day changes in the maximum temperature. Five-year running-mean AIDV values decreased significantly throughout the period. This trend was apparent for the region overall and for the 10 of the 20 study sites analyzed individually. Temporal variation in AIDV values was significantly related to mid-tropospheric flow patterns over the central United States. Meridional circulation was associated with smaller AIDV values in all sites except those in the northwestern and southeastern corners of the study area, whereas zonal flow was linked to larger interdiurnal temperature change. The analysis of selected individual years indicated that mid-tropospheric circulation patterns were more persistent with meridional flow, and surface cyclones and their associated surface fronts tracked through the study area less frequently than in years with zonal flow. Analysis at a daily temporal resolution revealed an added dimension of trends in temperature variability beyond those apparent with a coarser monthly resolution. These results emphasize the importance of finer temporal resolution in the analysis of both past and projected climate change; regionally summarized monthly temperature values mask important variation in temperature trends apparent at shorter temporal and more local spatial scales.  相似文献   
995.
This article presents thoughts on the conceptual design of the Xiament-Jinmen Bridge including design principles, natural conditions of meteorology, oceanography, topography, submarine morphology and seismic and engineering geology, and the economic benefits from the bridge.  相似文献   
996.
本文从理论上研究了在不同的背景西风条件下阻塞胚胎与局地天气尺度波之间的相互作用。结果发现合适的弱西风对阻塞的形成是至关重要的 ,较强的背景西风不利于阻塞的形成。同时局地天气尺度波的位置也起着重要作用。  相似文献   
997.
0418号"艾利"台风暴雨过程的数值模拟   总被引:5,自引:1,他引:5  
本文利用中尺度MM5模式模拟了0418号“艾利”台风造成闽东北强降水的一次物理过程.模拟结果表明:充沛的水汽和强烈的上升运动是造成台风暴雨的直接原因,降水与850hPa涡度场、散度场有较好的对应关系.基本流场存在二次切变时,横渡型扰动会激发产生并且发生不稳定,从而导致暴雨天气的产生.台风附近相当位温密集陡峭和CAPE值的突增表明台风有加强的可能,CISK和涡旋Rossby波的传播是可能的机制.水汽的敏感性试验结果表明:水汽变化会影响台风的强度和降水的强度,水汽的微小变化可造成降水极大的变化,但对台风的位置影响不大.  相似文献   
998.
Boundary layer observations were made over the Gulf of Mexico over a 3-year period in order to develop and test methods for estimating surface fluxes and boundary layer wind fields. In addition to routinely available buoy and CMAN surface data, six 915 MHz radar wind profilers (RWPs) and RASS profilers were mounted on oil platforms and on the shore. Estimates of surface momentum, sensible heat, and latent heat fluxes have been made from the surface observations using the COARE software. Simulations by the National Weather Service's Eta meteorological model are compared with the observations of surface fluxes and wind profiles. The boundary layer is found to be unstable over 90% of the time, and latent heat fluxes are about five to ten times larger than sensible heat fluxes, as usually found over tropical oceans. Eta model simulations of surface fluxes are within about ±50% of COARE estimates of the fluxes based on surface observations. Most of the time, COARE-derived fluxes at 11 sites are within a factor of two of each other at any given hour. In multi-day case studies, COARE calculations are found to agree with Eta model simulations of these fluxes and parameters within a factor of two most of the time. Eta model simulations of wind speeds in the boundary layer tend to exceed the RWP observations by 1–2 m s−1 near shore and by 2–6 m s−1 at distances of 100–200 km offshore.  相似文献   
999.
0407号台风"蒲公英"路径突然北折的原因分析   总被引:6,自引:0,他引:6  
高珊  何小宁  凌士兵 《台湾海峡》2005,24(4):448-454
本文主要从天气学的角度分析0407号台风“蒲公英”在巴士海峡上空突然北折的原因,发现双台风相互作用牵制了“蒲公英”,增加了台风路径北折的突然性,而其南侧高压环流的发展对台风路径北折有决定性作用.扩大传统中双台风发生作用的距离,将两个台风之间可以直接、半直接或间接作用的概念引入日常预报中。  相似文献   
1000.
闽南一次大范围飑线过程的分析   总被引:1,自引:0,他引:1  
张加春  潘宁 《台湾海峡》2003,22(3):364-368
本文对2002年4月6日发生于闽南地区的一次大范围飑线过程进行了天气学、雷达回波演变及气象要素变化等方面的分析,认为判断飑线发生与否不能仅依据本地气象要素的变化,雷达回波等信息将有助于对天气现象的正确理解。  相似文献   
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