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1.
Modern components of the technology ofhail suppression activities in the Republic ofMoldova are considered. The following elements of this technology are implemented: ASU-MRL software- and-hardware complexes; the corporate information network for cloud data acquisition and transmission based on the ASU-MRL data; Alazan’-6 and Loza-2 anti-hail complexes equipped with highly ac-ive crys-al-iz-ng components based on silver iodide; the guidance papers by the special-sts of the Special Weather Modification Service of the Republic of Moldova including those on the presentation of the radar echo of the horizontal cross-sections of clouds in the Lagrangian coordinate system; the improved methodology ofhail suppression activities. 相似文献
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E. I. Potapov G. S. Burundukov I. A. Garaba V. I. Petrov 《Russian Meteorology and Hydrology》2007,32(6):360-365
The weather modification technologies designed to mitigate hail damage for economic and social objects become more and more demanded, despite ambiguous estimates of their results and thus expediency of their practical use [15, 17]. In this connection, results of antihail work in the areas where this activity lasts for many years are of direct scientific and practical interest. The Republic of Moldova is a good example of such an area. Antihail shield, based on the rocket technology of reagent injection into the cloud, has been under operation for more than 40 years. In the paper, the conceptual basis of hail-dangerous Cb cloud modification technique are presented along with some data on modification results during the last 10 years; an optimistic estimate of the antihail shield efficiency in the country is obtained. 相似文献
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E. S. Nesterov Z. K. Abuzyarov G. A. Grigor’eva I. N. Davidan V. I. Dymov T. A. Pasechnik 《Russian Meteorology and Hydrology》2011,36(10):669-676
An estimate of the computation accuracy of wind waves is obtained on the basis of three mathematical models used for the diagnosis and forecast of wind waves at the Hydrometcenter of Russia, US National Weather Service, and European Centre for Medium-Range Weather Forecasts. The accuracy estimation was carried out for the whole year 2006 by means of the comparison of model computations based on different wind fields with hourly instrumental observations of waves at 16 buoys in the North Atlantic. The computation accuracy was estimated on the basis of six statistical characteristics. Besides, the estimates for various wave height ranges for months and seasons of the year are made for all buoys and grouped into three geographical areas: the coasts of the United States, Canada, and Great Britain. The essential differences are revealed in the accuracy of model-based computation of waves in the areas of the ocean with different wind wave regimes, in different seasons of the year, and within various wave height ranges. The obtained results indicate the necessity to improve the present-day methods of diagnosis and forecast of wind waves. 相似文献
4.
Do-Yong Kim Jin-Young Kim Jae-Jin Kim 《Asia-Pacific Journal of Atmospheric Sciences》2013,49(2):183-192
This study investigated multi-decadal variability in the wind resource over the Republic of Korea using the Weather Research and Forecasting (WRF) mesoscale meteorological model. Mesoscale simulations were performed for the period from November 1981 to November 2010. The typical wind climatology over the Korean Peninsula, which is influenced by both continental and oceanic features, was represented by the physics-based mesoscale simulations. Winter had windier conditions with northwesterly flows, whereas less windy with southwesterly flows appeared in summer. The annual mean wind speeds over the Republic of Korea were approximately 2 m s?1 with strong wind in mountainous areas, coastal areas, and islands. The multi-decadal variability in wind speed during the study period was characterized by significant increases (positive trend) over many parts of the study area, even though the various local trends appeared depending on the station locations. The longterm trend in the spatially averaged wind speed was approximately 0.002 m s?1 yr?1. The annual frequency of daily mean wind speeds over 5 m s?1 at the turbine hub height also increased during the study period throughout the Republic of Korea. The present study demonstrates that multi-decadal mesoscale simulations can be useful for climatological assessment of wind energy potential. 相似文献
5.
T. W. Krauss A. A. Sin’kevich R. Burger N. E. Veremei Yu. A. Dovgalyuk V. D. Stepanenko 《Russian Meteorology and Hydrology》2011,36(10):643-652
Changes are analyzed of a Cb cloud characteristics due to its merging with feeder clouds, on the data on a long-living Cb cloud in Saudi Arabia on July 4, 2008. Continuous radar and satellite observations of the cloud are carried out during 6 h. The Cb cloud development is also numerically simulated using a nonstationary 1½ model. It is found that the processes of Cb cloud merging with feeder clouds developing in its vicinities affect significantly the Cb cloud development. This impact demonstrates itself in longer duration of the Cb cloud life span, increasing top height, reflectivity, precipitation duration and intensity. Modification of the feeder clouds can accelerate their development, which eventually can affect notably the Cb cloud. 相似文献
6.
山东中西部后向发展雷暴初步研究 总被引：1，自引：1，他引：0
基于山东济南新一代天气雷达多年资料,首先提出后向发展雷暴的概念,并规定了普查标准。通过普查2005—2012年8年济南多普勒天气雷达资料,选取了75个后向发展雷暴个例,分析了山东中西部后向发展雷暴的统计特征,给出了常见的3种后向发展雷暴概念模型。选取典型个例,分别对3种类型后向发展雷暴的演变方式及其物理机制进行了初步分析,为山东中西部后向发展雷暴的生成和演变提供了初步的认识。结果表明:(1)后向发展雷暴主回波以带状为主,生命史1—5 h,最大反射率因子在50 dBz以上,移动路径有西—西北、西南、原地新生3种类型;(2)新回波初生时间发生在16—17时(北京时)最多,初生地点在鲁西北和鲁中山区一带,强度一般在30 min内超过40 dBz,生命史在1 h以上,74.7%的新生回波与主回波合并或连接;(3)山东省中西部具有后向发展特征的对流系统产生的灾害性天气以冰雹和雷暴大风为主,很少伴随暴雨灾害;(4)新回波的源地特征可以分为随主回波移动、沿同一方向延伸以及位于两雷暴群之间3种类型;多个雷暴群共存时,新回波的源地介于两个回波带之间,使二者逐渐趋为一体;(5)当主回波传播方向与其长轴相交时,其长轴方向转向,距离新回波较远的一侧减弱;当主回波传播方向与其长轴方向一致,新回波源地位于主回波长轴的延长线上时,主回波加强;(6)天气尺度系统为后向发展雷暴提供了条件不稳定的大气层结和丰富的水汽,地面辐合线和冷池前沿阵风锋是产生新雷暴的主要抬升触发机制;适当的低层垂直风切变有利于新雷暴持续产生并加强;地形的阻挡使新回波源地在同一地点停滞,冷池阵风锋在低层风引导下沿地形向下游移动,新回波源地也随之移动。 相似文献
7.
Do-Yong Kim Jin-Young Kim Jae-Jin Kim 《Asia-Pacific Journal of Atmospheric Sciences》2012,48(4):449-456
Wind speed is an important meteorological variable for various scientific communities. In this study, numerical mesoscale simulations were performed over the Republic of Korea in 2006, to produce wind information distributed homogeneously with space. Then, an attempt was made to statistically correct the simulated nearsurface wind speed using remotely sensed surface observations. The weak wind season (WWS, from May to October) and strong wind season (SWS, from November to April) were classified on the basis of the annual mean wind speed. Although the spatial features and monthly variation pattern of the near-surface wind speed were reasonably simulated in the Weather Research and Forecasting (WRF) model, the simulations overestimated the observed values. To correct the simulated wind speeds, a regression-based statistical algorithm with different constants and coefficients for WWS and SWS was developed using match-up datasets of wind observations and satellitederived variables (land surface temperature and normalized difference water index). The corrected wind speeds showed reasonable performance for both WWS and SWS with respect to observed values. The monthly variation in the corrected wind speeds over the Republic of Korea also matched better with observations throughout the year, within a monthly bias range of approximately ± 0.2 m s?1. The proposed algorithm using remotely sensed surface observations may be useful for correcting simulated near-surface wind speeds and improving the accuracy of wind assessments over the Republic of Korea. 相似文献
8.
A Numerical Study of the Urban Intensity Effect on Fog Evolution in the Beijing-Tianjin-Hebei Region 总被引：2，自引：0，他引：2 
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下载免费PDF全文 The influence of urban intensity on fog evolution in the Beijing-Tianjin-Hebei (BTH) region (China) is investigated numerically with the the Weather Research and Forecasting (WRF) model coupled with the urban canopy parameterization-building energy model (UCP- BEM) urban physics scheme. The experiments were designed with a focus on the influence of different urban intensities, which are represented by a different fractional coverage of natural land, buildings, and energy consumption inside buildings in an urban environment. The results of this study indicate that urban areas notably influence fog evolution when natural land is reduced to a small fraction (e.g., less than 10%). Developed land changes fog evolution through urban effects. Higher urban intensity (HUI) generally results in warmer temperatures and lower wind speeds throughout the day, while inhibiting morning specific humidity loss and afternoon specific humidity gain because of the HUI effect on surface heat flux, surface roughness, and surface moisture flux. HUI leads to later and weaker liquid water content formation, with a higher liquid water content base, primarily due to its effect on near surface temperatures. This finding implies that HUI may inhibit the conditions for fog formation. In addition, urban areas with equal natural and developed land coverage seem to greatly enhance the upward surface moisture flux, which is attributed to the combination of a relatively large potential evaporation on developed land and an ample moisture supply from natural land. As a result, the specific humidity increases in the afternoon. 相似文献
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Summary Two-thirds of the land mass of Taiwan island is covered by mountains that affect precipitation systems over the island. To understand the influence of such terrain on a precipitation system was one of the objectives of TAMEX (Taiwan Area Mesoscale Experiment, Kuo and Chen, 1990). During the passage of these precipitation systems, Doppler radar readings as well as conventional data were collected. On 17 June, 1987 a precipitation system moving toward northeastern Taiwan dumped over 100 mm of rainfall per day near the mountain foothills, not far from the ocean. Over the lee side, the precipitation amount was less. The radar data results indicate that a series of cells formed about 10 km upstream of the coastal area and moved toward the mountains under the influence of an easterly wind. The zonal speed was about 4 to 8 ms–1. The time interval for the formation of these convective cells was about 40 minutes. They intensified near the coastal area, the foot hills and the mountain slope, but their intensity decreased on the lee-side. A two-dimensional, nonhydrostatic model with a terrain-following coordinate system was employed to study the influence of environmental wind patterns and terrain on the characteristics of a precipitation system. Simulation results indicate that a series of clouds associated with an updraft formed at the middle level, about 10 to 20 km east of the mountain foothills (near the coast line), under the influence of easterly winds in a very moist environment. Then, updrafts associated with cloud water travelled westward from the cloudy region, intensifying near the bottom of the mountains and in the coastal areas due to orographic lifting. Then, convective cells formed. As these cells continued moving westward and upward near the foothills as well as the upslope area near the mountain top, their intensity increased. But once they passed over the mountain top to the lee side, their intensity decreased. The time interval for the formation of cells was about 35 minutes and the size of the cells was about 5 to 8 km horizontally. The numerical results are qualitatively consistent with the observations. Sensitivity studies indicate that the magnitude of the wind speed influenced the formation of the cells. The low level wind profiles affected the movement of cells on the lee-side of the mountain, and the height of mountain also had an impact on the characteristics of the precipitation cells.With 18 Figures 相似文献
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Radar observations of the evolution and hierarchy of Cb clouds in different regions of the Earth are generalized to present the concept of a life cycle of a mesoscale convective system; during the life cycle, the separate Cb clouds develop into hierarchic coordinated mesoscale clusters, which recurrently originate and are localized in fixed places in the system which moves as a unit. The rising dominant clusters generate quasi-periodic oscillations of maximum intensity and wavelike space structure of the precipitation field. The methodological principles of the concept are used for objective classification of precipitation systems based on morphological and evolutional features. They can be used in techniques of very-short-range forecasting of hazardous convective weather. 相似文献
11.
Weather forecasting in the Southern Ocean and Antarctica is a challenge above all due to the rarity of observations to be assimilated in numerical weather prediction(NWP)models.As observations are expensive and logistically challenging,it is important to evaluate the benefit that additional observations could bring to NWP.Atmospheric soundings applying unmanned aerial vehicles(UAVs)have a large potential to supplement conventional radiosonde sounding observations.Here,we applied UAV and radiosonde sounding observations from an RV Polarstern cruise in the ice-covered Weddell Sea in austral winter 2013 to evaluate the impact of their assimilation in the Polar version of the Weather Research and Forecasting(Polar WRF)model.Our experiments revealed small to moderate impacts of radiosonde and UAV data assimilation.In any case,the assimilation of sounding data from both radiosondes and UAVs improved the analyses of air temperature,wind speed,and humidity at the observation site for most of the time.Further,the impact on the results of 5-day-long Polar WRF experiments was often felt over distances of at least 300 km from the observation site.All experiments succeeded in capturing the main features of the evolution of near-surface variables,but the effects of data assimilation varied between different cases.Due to the limited vertical extent of the UAV observations,the impact of their assimilation was limited to the lowermost 1?2-km layer,and assimilation of radiosonde data was more beneficial for modeled sea level pressure and near-surface wind speed. 相似文献
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Atmospheric profiling with the UAS SUMO: a new perspective for the evaluation of fine-scale atmospheric models 总被引：1，自引：0，他引：1
Stephanie Mayer Anne Sandvik Marius O. Jonassen Joachim Reuder 《Meteorology and Atmospheric Physics》2012,116(1-2):15-26
For the first time, unmanned aerial system measurements collected by the small unmanned meteorological observer (SUMO) are used to evaluate atmospheric boundary layer (ABL) parameterization schemes embedded in the Advanced Weather Research and Forecasting model (AR-WRF). Observation sites were located in the vicinity of the almost idealized shaped mountain Hofsj?kull, Central Iceland. SUMO profiles provided temperature, relative humidity and wind data to maximum heights of 3?km above ground. Two cases are investigated, one with calm wind conditions and development of a convective ABL and one with moderate winds and gravity waves over Hofsj?kull. For the high-resolution simulation with AR-WRF, three two-way nested domains are chosen with a grid size of 9, 3 and 1?km. During its first meteorological test, SUMO has proved its great value for the investigation of the diurnal evolution of the ABL and the identification of mesoscale features residing above the ABL, such as subsidence. 相似文献
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中国卫星FY-3A水汽产品为大气水汽混合比,对大气各层水汽条件具有精细化描述能力。将卫星水汽混合比空间分布与区域流场对应叠加,进行综合量化分析,是目前卫星监测反演数据研究分析与业务应用的形式之一。由于卫星数据与流场数据为非同源数据,具有各自的坐标系,综合分析需要将坐标系统一,卫星坐标系随时间变化,因此向固定的流场坐标系转化。整个数据预处理过程,包括卫星数据插值至标准等压面层,卫星轨道网格转为经纬等距标准网格;双权重法异常数据剔除;平滑滤除高分辨率"噪音";十折交叉相关检验确认卫星资料精细化特征保持良好。对流场分析首先选择关键系统,江淮梅雨强降水系统主要为浅薄低涡和辐合线,近5 a的统计显示3/5的低涡活跃在江南,2/3的辐合线活跃在淮北。诊断分析合成的江淮梅雨强降水典型系统,获得辐合线系统纬向湿度锋区更强,低涡系统湿舌经向度大,显示更多干湿气团混合。进而将预处理后的FY-3A水汽分布与强降水系统低层流场对应时刻综合比对,结果显示:与流场气旋性辐合区对应的卫星湿区对强降水落区具有精细化指示性。同时FY-3A湿度产品计算的大气低层(1 000~850 h Pa)可降水量、以及降水区对应的假相当位温高能区及高能锋区,均与降水强度呈正比关系。将卫星水汽资料诊断方法应用于近海海域,可估测系统强降水落区以及降水强度,有利于改善海上缺乏降水观测站的问题。 相似文献
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T. W. Krauss A. A. Sin’kevich N. E. Veremei Yu. A. Dovgalyuk V. S. Makitov V. D. Stepanenko 《Russian Meteorology and Hydrology》2011,36(3):167-174
Development of a long-living Cb cloud in the desert part of Saudi Arabia on April 10, 2008 is analyzed. Continuous satellite and radar observations of the cloud are carried out during five hours. Numerical modeling of the cloud is performed using a nonstationary 1.5-dimensional model. Data on the Cb cloud and its anvil development dynamics are obtained. It is shown that the anvil characteristics differ significantly in the zone of its formation directly over the cloud and when moving away from it. It is pointed out that the radar underestimates the anvil sizes. Estimation of precipitation rate from the cloud under study by means of satellite and radar measurements is compared against the results of numerical modeling. It is found that precipitation rate could reach 100 mm/h. The radar estimates of the precipitation rate are significantly overstated, which is, in this case, due to presence of large hail particles. 相似文献
17.
石爱丽 《中国气象科学研究院年报》2008,(1):44-44
人工影响天气中心有5名专家参与了奥运会及残奥会开闭幕式消减雨技术保障工作,提供现场技术指导。专家们应用“十一五”科技支撑项目“人工影响天气关键技术与装备研发”的相关研究成果,为奥运人工消雨提供卫星、雷达和数值模式模拟等技术产品,为奥运会及残奥会开闭幕式的人工消减雨工作的成功提供了强有力的科技支撑。因在北京奥运气象服务中表现突出, 相似文献
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该文初步建立了青岛奥帆赛高分辨率数值模式系统（包括预报模式和释用模式）。预报模式基于Weather Research & Forecast（WRF）模式V3.0,模式设计为网格数60×50×38,水平分辨率500 m。在IBM小型机上用8个线程作15 h预报所需机时约为1 h 20 min,可满足实时业务预报需要。利用高分辨率边界层模式和城市小区尺度模式对该预报结果进行了动力释用（水平分辨率分别为100 m和10 m）。该模式系统于2008年夏季进行了实时运行试验,模式产品在北京奥运气象服务中心青岛分中心使用。结果表明:该模式系统有较强的稳定性和实用性,对城市热岛、海陆风、地形及建筑物影响等局地环流特征有较好的模拟效果。数值试验分析表明:城市化引起城市热岛效应,增大了海陆温差,使海风加强;城市建筑物拖曳作用使风速减小,从而使海风推进速度减缓;精细下垫面资料的引入对海风等局地环流高分辨率数值模拟至关重要。 相似文献
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利用中尺度非静力WRF(Weather Research and Forecasting)模式及其三维变分同化系统,对2007年7月淮河流域的一次强降雨过程进行多普勒雷达径向速度资料的三维变分同化试验,重点考察雷达资料的不同稀疏化方式对同化结果以及对暴雨数值模拟的影响。结果表明:同化多普勒雷达径向速度资料使得模式初始风场包含了更丰富的中尺度特征信息,有效调整了初始场的环流结构,能够改善模式对暴雨过程的模拟效果;以不同的稀疏化处理方式同化多普勒雷达径向速度资料对分析场会产生不同的影响,进而影响模式的降水预报效果,本次试验中当极坐标网格径向分辨率取10 km的时候降水过程的预报效果最好。 相似文献