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1.
以2005年严重影响我国的登陆台风Haitang为研究对象,在用MM5模式成功模拟台风登陆前后路径、强度、降水以及结构特征的基础上,通过地形敏感性试验,分析了地形对台风的影响及其机理。结果表明:台风在经过台湾及其后在福建登陆期间的异常路径是地形诱生低压发生发展的结果;在降水强度上东部沿海特殊地形对台风北侧东南气流的辐合抬升使得暴雨增幅度1倍以上;地形对台风强度也有一定影响,约为4~5hPa。通过对有无地形影响时台风结构的比较发现地形影响主要在低层,使得高度场分裂两个中心,低层台风主体受山脉阻挡在位置上落后于高层。分析还发现台风登陆前夕移动方向西侧相当位温向西倾斜也可能与地形有关。  相似文献   

2.
以2005年严重影响我国的登陆台风Haitang为研究对象,在用MM5模式成功模拟台风登陆前后路径、强度、降水以及结构特征的基础上,通过地形敏感性试验,分析了地形对台风的影响及其机理。结果表明:台风在经过台湾及其后在福建登陆期间的异常路径是地形诱生低压发生发展的结果;在降水强度上东部沿海特殊地形对台风北侧东南气流的辐合抬升使得暴雨增幅度1倍以上;地形对台风强度也有一定影响,约为4~5hPa。通过对有无地形影响时台风结构的比较发现地形影响主要在低层,使得高度场分裂两个中心,低层台风主体受山脉阻挡在位置上落后于高层。分析还发现台风登陆前夕移动方向西侧相当位温向西倾斜也可能与地形有关。  相似文献   

3.
三个登陆浙江热带气旋数值试验及暴雨过程的湿位涡分析   总被引:1,自引:2,他引:1  
首先利用非静力平衡中尺度数值模式MM5(V3)对2004年3个登陆浙江热带气旋的登陆过程进行了数值模拟试验,通过对路径、降水的对比验证表明,MM5模式对热带气旋的模拟是比较成功的。然后在模拟效果较好的基础上,利用高分辨的模拟结果,对台风暴雨过程的湿位涡进行了诊断分析,结果表明:3场台风暴雨的形成机制有显著差异,Rananim强降水是由其本身环流造成的,至于Mindulle和Haima的降水冷空气的侵入起到了重要作用。暴雨都发生在陡立密集区附近,对流层低层湿位涡负值中心与暴雨落区存在较好的对应关系,而其中心数值绝对值随时间的变化量与1h降水存在正相关关系,说明湿位涡负值中心可以作为降水时空分布的重要指标,为台风暴雨预报提供一种思路。  相似文献   

4.
影响福建沿海的0010号"碧利斯"台风暴雨的地形敏感性试验   总被引:9,自引:4,他引:9  
采用MM5模式,以2000年10号(0010)台风“碧利斯”为个例,选取台风登陆前后时段,采用不同地形高度来模拟该时段台风暴雨过程.试验结果表明福建东部沿海的特殊地形对登陆福建中部沿海的台风暴雨有着明显的增幅作用.用3个不同区域每隔3h面雨量作比较,并通过对不同方案的垂直风速及不同时段的水平流场进行分析,可见其地形对台风暴雨的最大增幅作用发生在山脉迎风坡的地形坡度与气流正交速度乘积最大的时段.  相似文献   

5.
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   

6.
多普勒雷达资料在近海强台风模拟中的同化试验   总被引:1,自引:0,他引:1  
利用中尺度数值模式(WRF),并同化了多普勒雷达反射率和径向速度资料以及非常规的观测资料,对近几年登陆于浙闽沿海的4例强台风进行了数值模拟。通过高时空分辨率的模拟结果对比分析表明:雷达资料的同化,对近海登陆台风路径和降水模拟以及中尺度降水特征都有进一步改进的效果;模拟较好的揭示了台风近中心螺旋云带中的强中尺度对流系统。通过模拟分析表明,在台风近中心的螺旋云带中,低层有一条强辐合线存在,它与实况多普勒雷达给出的低层平显(PPI)强度回波带有较好的对应关系,也与沿海地区中尺度暴雨系统紧密联系,并由此看到近海海域降水带和强对流区的存在。  相似文献   

7.
台风“杜苏芮”(2305)是1949年至2023年9月登陆福建第2强台风,引发福建极端强降水。利用双偏振雷达、FY-4A等多源观测资料分析了福建强降水发展的主要特征,指出2个明显的降水阶段分别由台风眼壁与内螺旋雨带、台风外螺旋雨带造成。“杜苏芮”登陆后眼壁附近中β尺度对流云团发展,云团低层以大雨滴为主,对流云团分裂进入内螺旋雨带中发展为线状对流,数密度更高的较大雨滴产生极端雨量。而台风移出福建后外螺旋雨带后部对流组织化,形成带状中尺度对流系统,通过“列车效应”持续影响福建沿海,产生极端强降水,高浓度小雨滴是主要的云微物理特征。降水与鹫峰山、戴云山地形密切相关,向东开口的喇叭口地区利于形成强降水中心。  相似文献   

8.
"碧利斯"台风暴雨物理量场诊断分析   总被引:14,自引:4,他引:10  
本文用MM5模式数值模拟了0010号“碧利斯”台风登陆福建的过程,表明MM5模式能很好地模拟出主要雨带及其分布特征。物理量场分析指出,本次福建沿海地区暴雨产生的物理机制主要有:台风登陆福建前后福建沿海地区上空层结相当不稳定;由于台风环流非对称性,台风中心北侧中低层有很强的风速、相对湿度、正涡度、辐合、垂直速度:暴雨区高低层存在正负螺旋柱;暴雨区高层存在正湿位涡、低层负湿位涡中心。  相似文献   

9.
台风Fitow降雨的数值预报试验   总被引:11,自引:0,他引:11  
用MM5对热带气旋Fitow(2001)的登陆过程进行了成功的预报,特别是对台风暴雨中心的位置和降雨量的预报与实况相当吻合。敏感性试验表明,华南地形对本次台风登陆过程中心气压和位置的变化没有明显的影响,但对台风低压北侧还是有一定的阻挡填塞作用,尤其是对24h累计的降水量有明显的增幅作用,而华南地形的这些影响主要是由南岭山脉所造成的。由于南岭山脉的阻挡,使南来的暖湿气流强迫抬升,促进了对流活动和降水系统的发展,最终造成台风降雨量明显加强,其增幅达30%。  相似文献   

10.
利用多普勒雷达加密资料对发生在闽南的一次台风尾流暴雨进行中尺度分析。结果表明 ,这次暴雨过程由两阶段暴雨组成 :第一阶段暴雨是由海上形成的中尺度气旋造成的 ;第二阶段暴雨是由切变线上的强辐合及切变线上形成的边界层中尺度气旋造成的。暴雨雨带的形成主要与“逆风区”、气流辐合、边界层急流、切变、地形有关。  相似文献   

11.
The analysis of the structure of the cryolithozone, facies, and thicknesses of the Quaternary sediments and the results of the physicochemical mathematical modeling of the modern shelf of the western part of the Laptev Sea support the influence of the Late Pleistocene glaciations on the heat conditions and the distribution of the permafrost in the area. A ~200-m thick glacier formed under aerial conditions from atmospheric precipitation represented the metamorphosed snow cover. According to the modeling, the long-living (from 60?50 to 10?4 ky) glacier reduced the thickness of the permafrost rocks in the reviewed shelf area for 280–360 m. The Holocene marine transgression additionally decreased the thickness from 50–140 m on the inner shelf to 220–350 m on the outer shelf. The modern submarine cryolithozone 450-0 m thick is wide-spread in the studied region from the coast to the shelf boundary (isobaths of 130–140 m), where it pinches out at a distance of ~380 km from the coast at a depth of ~250 m above the sea level.  相似文献   

12.
We analyze the components of the carbon system of the Sevastopol bay waters and the balance of main sediment-forming substances using the data of field investigations in 1998–2008. The interannual variations of total inorganic carbon and the equilibrium partial pressure of carbon dioxide in the bay water are noted. An increase in the flux of carbon dioxide into the bay and in the content of organic carbon in bottom sediments is revealed, and an explanation of this phenomenon is given. The priority accumulation of organic carbon in the sediments of the bay is established. We assess the interannual variation in the relative abundances of organic and inorganic carbon as an index of the carbon cycle stability.  相似文献   

13.
We generalize and analyze the state of investigations of the influence of river waters on the hydrologic structure of the Black Sea. Specific features of the water, regime and hydrography of rivers flowing into the sea, data on the discharge of rivers, and intrayear and interyear variability of the discharge are presented. We discuss and analyze works studying the transformation of river waters, routes of desalinized sea waters, and their influence on the thermohaline structure and dynamic regime of the sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

14.
We analyze the results of numerical calculations performed according to the three-dimensional interdisciplinary model of an ecological system of the Black-Sea shelf zone near the estuary of the Danube. The complete system of equations of hydrothermodynamics is solved together with transport equations of the advection-diffusion-reaction type used to describe the transformation of a substance (nitrogen) between the components of the characteristic vectors of the ecosystem: plankton, detritus, and biogenic elements (nitrates). We describe the distinctive features of the circumcontinental distribution of components obtained as a result of numerical experiments and present arguments for the conclusion that the ecosystem of the Danube estuary water area plays the role of a buffer zone between the press of the Danubian biogenic pollutions and the neighbouring areas of the shelf zone and open sea. Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

15.
Ten years of semistationary studies of the interaction of the ice cover and the coastal relief of the Kandalakhsa Gulf in the White Sea allowed us to reveal the peculiarities of these processes in the warm and cold years and the mechanisms of the origination of ice forms, including ice tents, which govern the character of the tidal flats. Three dynamic fast ice zones are distinguished by their geomorphological location, morphology, and ice dynamics. The dependence of the mechanisms and volumes of the enrichment of the fast ice in the sediments on the coastal zone??s relief was established. At the coast of the Kindo Peninsula (Velikaya Salma Strait), the ice mostly contains fine-sandy sediments. Coarser sediments, including boulders, are occasional and frozen into the ice at the contact of the fast ice and the bottom. At the expense of the ice??s spreading by 4?C6 times in the warm years and 2?C4 times in the cold years, several thousand tons of sediments mostly from the tidal flat??s surface (100?C700 m3 from 1 km of coast in the wide tidal flats and <50 m3 on the steep coasts) are delivered to the water area.  相似文献   

16.
A relationship between paths of the Kuroshio and Kuroshio Extension (KE) is investigated, using the satellite-derived altimetry dataset of 1993–2008. When the Kuroshio takes the nearshore nonlarge meander path or typical large meander path and resultantly goes through the deeper channel (about 2500 m) of the Izu-Ogasawara Ridge, the KE path adopts a relatively stable state with the two quasi-stationary meanders. On the other hand, when the Kuroshio takes the offshore nonlarge meander path and then passes over the shallower part of the Ridge (about 1000 m), the KE path tends to be convoluted, i.e., an unstable state.  相似文献   

17.
We use many-year archival observations of hydrologic and hydrobiologic state of the Sea of Azov for the identification of the structure of a model of its ecosystem. The ecosystem model, supplemented with expert estimates of bioresource consumption (fish reserve), contamination level, and possible ecologic fines for violation of the sea natural state, is formalized by the method of system dynamics. Hereat, the major part of influence functions is found in terms of observational data with application of self-organization algorithms. We also present the results of simulated experiments with the model of the ecosystem, which enable us to analyse scenarios of its behaviour under the influence of various external factors (wind, river discharge, water exchange with the Black Sea, etc.). Translated by Peter V. Malyshev and Dmitry V. Malyshev  相似文献   

18.
Izvestiya, Atmospheric and Oceanic Physics - Analysis of the temporal variations of the virtual heights of the sporadic E layer (h?ES) determined from ionograms with increased accuracy (1...  相似文献   

19.
The methodology and the first results of the computations of the volumes, masses, and growth rates of the sedimentary body of the buried Black Sea basin are presented. Their temporal evolution reflects the regional paleogeodynamics, in particular, the reorientation of the vector of the relative movement of the Arabian and Eurasian lithospheric plates and the related intensification of their collision in the late Miocene-Pliocene.  相似文献   

20.
The spatiotemporal variability of the hydrochemical composition of the riverine runoff in nearmouth areas is presented using the example of selected rivers of the Arctic Basin. The temporal dynamics of the riverine nutrient runoff are mainly determined by the seasonal and interseasonal variations in the drainage basins. The spatial variations in the chemical composition of riverine waters in the near-mouth areas are mainly caused by the dynamics of the water flow and the river bed relief and, to a lesser degree, by biochemical processes. It is shown that the variations in the nutrient composition of the waters in near-mouth areas are comparable in magnitude to those at the river-sea geochemical barriers.  相似文献   

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