共查询到20条相似文献，搜索用时 547 毫秒
1.
A. A. Sinkevich T. W. Krauss V. D. Stepanenko Yu. A. Dovgalyuk N. E. Veremey A. B. Kurov L. V. Pivovarova 《Russian Meteorology and Hydrology》2009,34(12):775-783
Results are presented of analysis of development of a cumulonimbus cloud anvil with the top height exceeding 18 km, as observed
in Central India. The anvil development is studied using the measurements from Meteosat-5 and with the WR-100 radar. Minimum
air temperature measured from the satellite at the cloud top level is −105°C. The rate of cloud top height growth is, on average,
0.5 m/s. Horizontal extent of the anvil in the steering flow direction reached 85 km, and rate of the anvil propagation in
horizontal direction was equal to 32.4 km/h. The anvil area, after the satellite data, reached 3675 km2. After the radar data, horizontal extent of the anvil reached 50 km, maximum area being 600 km2. Analysis of discrepancies between the satellite and radar measurements of the anvil area shows that a significant part of
the anvil cannot be detected by the WR-100 radar because its potential is not enough high; the satellite measurement data
improve significantly quality of information on the Cb characteristics. 相似文献
2.
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
3.
A. A. Sinkevich T. W. Krauss S. D. Pavar N. E. Veremei Yu. A. Dovgalyuk A. B. Kurov V. Gopalakrishnan 《Russian Meteorology and Hydrology》2014,39(9):577-589
Considered is a case of the development of the cumulonimbus cloud (Cb) in the southwestern part of Saudi Arabia under the conditions of heavy pollution of atmosphere with natural aerosol. Using the ground-based radar and satellite radiometric instruments, the characteristics of the Cb are obtained for the cloud top height of more than 14 km and maximum reflectivity of 58 dBZ. To measure the precipitation rate using the radar data, the Z-I ratio obtained for the area under study was applied. To compute the precipitation rate, the results of the sounding with the SEVERI radiometer installed on the Meteosat-8 satellite were also used. Carried out are numerical experiments on the simulation of aerosol effects on the evolution of the cloud under study. The development of the cloud at the presence of background aerosol was simulated as well as at high aerosol concentration. Three cases are considered: aerosol is a passive admixture; aerosol has hygroscopic properties; aerosol has ice-forming properties. It is demonstrated that the most considerable effects on the cloud evolution are caused by the intensification of ice formation under the influence of aerosol; not only the time distribution of precipitation rate changes but also the amount of precipitation increases. 相似文献
4.
雷达反射率因子垂直廓线研究和多种遥感资料综合估计降水 总被引：9，自引：0，他引：9
利用同一Ｚ－Ｉ关系下地面降水与雷达回波强度的空间最佳匹配思想,提出了一种定量降水的新方法：考察Ｉ－Ｈ曲线,确定与地面的雨量计资料最相近的Ｉ值的所在高度,然后此用此高度上的Ｉ值反演降水。发现降水与很多因子有关,而云顶温度,反照率及云顶温度的时间梯度最为明显。研究表明用多因子方程估计降水效果较好。 相似文献
5.
A complex method for analysis of measurement data of the AVHRR radiometer of the NOAA satellite is presented, which allows detecting clouds, classifying their types, detecting precipitation zones, and estimating cloud and precipitation parameters in the daytime the year round in the midlatitudes. Tuning and testing of the method (threshold algorithms of classification) are carried out on the synchronous satellite and surface meteorological and radar data archive for central European Russia in 1998–2006. As a result of validation, characteristics are presented of reliability of satellite estimates of cloud amount, top height, maximum liquid water content in the cloud layer, and precipitation rate. 相似文献
6.
Comparison of cloud-top height retrievals from ground-based 35 GHz MMCR and GMS-5 satellite observations at ARM TWP Manus site 总被引：2，自引：0，他引：2
Retrievals of cloud-top heights from the ARM 35 GHz Millimeter Wave Cloud Radar (MMCR) located on Manus Island are compared to those from the GMS-5 satellite as a means to evaluate the accuracy of both MMCR and GMS-5 retrievals, as well as to ascertain their limitations. Comparisons are carried out for retrievals of both single-layer and multilayer clouds as seen by radar, but only for satellite-detected clouds with 100% amount within a 0.3×0.3° domain centered at the ARM site of one cloud type (i.e., low, middle, or high). Mean differences, with 95% confidence limits, between radar- and satellite-retrieved cloud-top heights (i.e., radar-retrieved cloud-top heights−satellite-retrieved cloud-top heights) are 0.3±0.3 km for single-layer clouds and −0.7±0.3 km for multilayer clouds. The study reveals that for thick clouds (i.e., cloud base ≤1 km and cloud thickness ≥10 km), which are representative of convective towers with no/light precipitation as well as thick anvil clouds, retrievals from the MMCR agree well with those from satellite with mean differences of 0.0±0.4 and −0.2±0.3 km for single-layer and multilayer clouds, respectively. For clouds of lesser thickness, mean cloud-top heights derived from satellite are lower than those derived from radar by as much as 2.0 km. It is also shown that for convective clouds with heavy precipitation, MMCR retrievals underestimate the cloud-top heights significantly. 相似文献
7.
A. A. Sin’kevich Yu. P. Mikhailovskii Yu. A. Dovgalyuk N. E. Veremei E. V. Bogdanov A. Kh. Adzhiev A. M. Malkarova A. M. Abshaev 《Russian Meteorology and Hydrology》2016,41(9):610-619
The results of synchronous radar, radiometric, and lightning-detection measurements are analyzed to reveal interrelations between the parameters of electric discharges and the parameters of cumulonimbus clouds developing in the North Caucasus. The dependences of electric activity of the cloud on radar parameiers as well as on the parameiers reirieved from Meteosat SEVIRI radiometer measurements are considered. Electric discharges (intracloud discharges and lightnings) were registered for 1 hour 40 minutes (the maximum frequency was equal to 448 discharges per minute). The relation ships are identified that connect the parameters of electric discharges with the precipitation rate and with the field of cloud top temperaiure. It was found that the frequency of eleciric discharges increases as the precipitation rate increases. The maximum frequency is reached at the precipitation rate equal to 70 mm/hour. Normalized autocorrelation functions ofthe field ofcloud top temperature retrieved from the satellite data are constructed. The high correlation is revealed between the scale of inhomogeneity of the field of cloud top temperature and the frequency of electrical discharges. 相似文献
8.
M. Bolliger P. Binder H. P. Roesli H. Wanner 《Meteorology and Atmospheric Physics》2004,87(4):219-234
Summary In autumn 1999 during the field phase of the Mesoscale Alpine Programme (MAP), the geostationary satellite Meteosat-6 performed 5-minute rapid scan imagery over central Europe. The rapid scan data of 11 heavy precipitation events are investigated by analyzing the spatial and temporal characteristics of cloud top structures. The objectives are to separate convective from stratiform cloud regions by satellite data alone and to gain insight into the life cycle of heavy precipitation systems. For verification of the satellite-based results, radar data from the operational Mt. Lema C-band radar is interpolated on the spatial grid of the infrared and visible Meteosat images. The interpolated radar data of each single grid cell is then classified by a convective-stratiform algorithm and compared to the analysed rapid scan imagery.The satellite- and radar-based approaches do only rarely produce matching classifications concerning the identification of convective areas. Since convection during the field phase of MAP occurred mostly embedded within stratiform cloud regions, no temporal and spatial characteristics of convective activity within clouds can be systematically derived from satellite imagery. This lack of characteristic cloud top structures prevented the unambiguous identification of typical cloudiness associated with stratiform precipitation. It is one of the major findings of this study, that in several cases being classified as stratiform by radar, strong cloud development is observed in satellite imagery. The preferred area of strong cloud development is located ahead of the Alpine barrier in a precipitation-free atmosphere. Two contrasting examples of life cycles of heavy precipitation systems are given based on the complementary information extracted from satellite and radar data. 相似文献
9.
10.
Considered is a case of the cumulonimbus cloud development in the southwestern part of Saudi Arabia with a very high precipitation intensity. The height of the cloud top amounted to 14 km and the radar reflectivity, to 60 dBZ. Carried out is the comparison of remote methods of measuring the intensity of precipitation from the cloud under study: the radar (using the relationship between the reflectivity and precipitation intensity) and satellite IR-radiometric (based on the results of sounding with the SEVERI radiometer installed at the Meteosat-8 satellite) methods. A split-window technique was used for detecting the position of the cloud top from the radiometric observations. The analysis enabled to select the best relationships for estimating the precipitation intensity from the data of radar and satellite measurements. The computations based on these relationships correspond most closely to the ground-based measurements with the precipitation gage. 相似文献
11.
一次强飑线云结构特征的卫星反演分析 总被引：1，自引：0，他引：1
利用NOAA卫星AVHRR资料,对2006年4月28日山东一次春季强飑线过程进行了分析,重点研究了卫星资料多光谱综合分析的强对流云微物理特征和卫星识别的对流强信号,并与雷达、FY-2C卫星观测资料进行了对比分析。结果表明:(1)RGB合成图能清晰地显示云顶的结构、纹理、云砧、组成、高度及云厚等信息,是一种很方便的分析工具。(2)多光谱综合分析归纳出卫星探测对流强信号:云顶的对流结构和纹理突出,有明显的云砧,云顶以小粒子为主,粒子有效半径Re随高度增长缓慢,云团上部存在明显的Re随高度递减带,云顶Re和-dRe/dT能定量指示对流的强弱。据此,卫星识别出强中心A比实际降雹提前了近1h,比飑线发生提前了2.5h,比多普勒雷达监测提前了近2h,特别是识别出的强中心B比实际降雹提前了近4h。卫星探测为强对流天气的监测预报和预警提供了一种新途径。 相似文献
12.
使用中尺度数值模式WRF中的双参数云微物理方案WDM6针对2008年台风“凤凰”登陆过程中造成的强降水进行数值模拟,通过卫星模拟器利用MTSAT-1R和TRMM卫星观测的红外云顶黑体亮温TBB、PR雷达反射率资料使用统计方法验证模拟结果。通过修改云水向雨水自动转化过程、冰晶核化过程、雪和霰的下落末速度、雪和霰的截距进行敏感性试验,减小模拟结果和卫星观测结果的差异。研究结果表明:WDM6方案模拟的台风“凤凰”登陆后的降水,强对流云系及对流柱状雷达回波基本符合实况,但模拟结果局部偏强。WDM6方案模拟产生了较多的浅对流云,低估了对流云系的出现频率。不同云类型模拟的雷达回波均偏强,对流云系雷达回波垂直分布接近观测。敏感性试验结果说明修改WDM6方案中云水向雨水自动转化率有效地改善了模拟效果。同时发现云滴初始数浓度影响云水向雨水自动转化率并最终影响云系结构和雷达反射率的模拟结果,过高的云滴初始数浓度会使模拟结果变差。 相似文献
13.
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(2):102-111
Basing on airmass motion trajectory calculations over the Arabian Peninsula on April 10, 2008, it can be assumed that in the lower and middle troposphere, zones with increased air moisture exist due to air inflow from the Red Sea. As a result, mesoscale volumes of dry and moist air are neighboring, though large-scale field is comparatively homogeneous with low humidity. In the mesoscale zones, intense thunderstorm and hailstorm Cb clouds developed, whose characteristics and evolution are studied in the paper. Continuous radar observations of the clouds are carried out during 5 hours. Numerical simulation of the cloud evolution is performed with nonstationary 1.5-dimensional model. It is noted that under the mentioned atmospheric conditions, in the area under consideration, heavy rain and hail from the Cb clouds are observed. The main factors of their origination are high thermal instability of the atmosphere and moist air inflow from outside. 相似文献
14.
15.
降水性层云含水量跃变对应的微结构观测研究 总被引：1，自引：0，他引：1
利用长春2007年5月16日的一次层状云降水过程的飞机观测资料,并结合天气图、卫星云图及雷达回波等资料,综合分析了此次降水过程中粒子浓度、粒子谱、雷达垂直累积液态水（vertical integrated liquidwater,VIL）、微波辐射计积分液态水（liquid water content,LWC）以及地面雨强特征。研究表明,层状云微结构在水平方向上的起伏较大,出现两次典型的含水量跃变：第1次液态水跃变主要是因为粒子浓度增加;第2次液态水跃变是因为粒子浓度和粒子谱共同作用的结果;雷达VIL值和地面雨强两者呈正相关。 相似文献
16.
Investigation of Cb motion in the province of Alberta (Canada) 总被引：1，自引：0，他引：1
Cb motion is analyzed in the paper. Strom observations were carried out in the province of Alberta (Canada) in 2005 with the help of radar. A new approach, based on determination of the vector of cloud track between radar scans, was used to study motion characteristics. Results of observations have shown that storms moved straight with some offset to the right in most cases. The merging of cells can significantly change storm track in some cases. The data obtained do not permit us to make a conclusion about the impact of seeding on cloud motion. 相似文献
17.
利用飞机、雷达、卫星观测资料,对2014年5月1日08时—2日08时河北省一次降水性层状云结构特征进行综合观测分析。结果表明本次过程降水云大致分为3层:4 200~2 850 m为冷暖云结构,2 162~2 174 m为十几米厚的纯暖云,近地面层121~265 m有粒子浓度较低(量级为101cm-3)的暖云。降水开始前存在较明显的催化云—供给云结构,降水开始后高层对低层有催化作用。人工增雨潜力区主要位于3 100~4 000 m,对应的雷达回波强度为20~30 d Bz,且雷达回波强度垂直梯度明显变小。对不同高度的云微物理量进行相关性分析,结果表明,云底的液态水含量和云滴浓度与气溶胶浓度具有较强的负相关,过冷水含量与云滴浓度相关性达到0.434,云凝结核浓度在冷云中与温度相关性较强,相关系数达到0.717。 相似文献
18.
上海地区几类强降水雨滴谱特征分析 总被引：3，自引：3，他引：0
用Parsivel激光降水粒子谱仪资料对2013年上海地区4—10月份期间4种类型 (层状云、对流暖云主导型、对流冷云主导型和强台风影响下的混合暖云型) 降水过程的雨滴谱特征进行了分析。通过平均雨滴谱及其拟合特征、雨滴数密度与含水量分布、雨滴尺度与速度二维谱分布等对比分析发现:各类降水中, 雨滴谱的峰值结构与雨强大小有关, 其中直径介于0.187~1.312 mm的小雨滴均出现峰值且总数最多。各尺度雨滴数密度及其比例决定了其降水量贡献比, 在冷云强降水中的雨强贡献最大的雨滴尺度要显著大于其他3种类型。雨滴谱宽按大小排列依次为对流冷云主导型、混合暖云型、对流暖云主导型和层状云。最后综合运用雨滴谱、雷达、雨量站、闪电等观测资料对9月13日对流冷云主导型降水过程进行分析后发现:在雷暴的演变过程中, 雨滴谱特征与雷达反射率因子、垂直液态水含量、自动站雨强、闪电频次等要素均有较好的相关性。冷云产生的冰晶和冰雹融化后的大雨滴进入中低层的广谱小雨滴群, 并通过破碎分裂增加了大雨滴的形成概率, 尤其是捕捉碰并过程更加快了大雨滴的增长速度, 使雨强在短时间内迅速加强。雨滴谱中各档粒子数的演变, 揭示了降水强度的变化, 用雨滴谱资料可有效弥补现有雷达定量估测降水的偏差, 且在冷云中改善明显。 相似文献
19.
河北春季一次飞机人工增雪的综合分析 总被引：1，自引：0，他引：1
2013年4月19日,河北省人工影响天气办公室在河北中南部地区根据云系特点首次采用多层次水平催化和垂直验证的方式对层状云进行人工催化和探测。本文利用机载仪器所取得的飞机探测资料,结合实时天气、卫星、雷达、探空和雨量观测资料,分析了河北春季层状云增雪作业的技术指标,探讨了航测微物理参量和卫星、雷达、探空等资料在作业中的应用。结果表明：云在发展期雷达回波由15 dBZ逐步上升到25-35 dBZ,卫星反演的云顶高度、云顶温度、有效粒子半径、光学厚度等都有增加;云在中后期有效粒子半径、光学厚度、液水路径迅速下降,雷达回波同时减弱。在高度3 177-5 723 m之间过冷云滴达100-700个/cm^3,含水量在0.01 g·m^-3左右,最大0.081 g·m^-3,云粒子主要在此增长,形成降水粒子,该区间适宜催化。作业后,影响区内云体发展,雷达回波增强,出现35 dBZ强回波,且强回波中心扩大;卫星反演的云顶高度、光学厚度等比对比区有明显增加。 相似文献
20.
一次对流云团合并的卫星等综合观测分析 总被引：3，自引：2，他引：1
利用FY2C卫星观测反演得到的云物理特征参数,结合雷达、微波辐射计和地面雨量等资料,综合分析了2008年7月17日中国安徽一次强降水过程的云合并特征。结果表明：对流云团发展合并是这次强降水发生的主要原因,同一区域内FY2C卫星反演的云光学厚度、雷达回波以及地面降水的分布演变具有较好的一致性,强降水落区与云光学厚度大值区以及雷达强回波区基本对应;对流云团中的液水分布不均匀,以团块状结构为主,对流云团合并时,常先有云体上部（云顶）的合并,一旦云中不均匀的液水合并,合并部位的云光学厚度迅速增加,地面微波辐射计观测的整层液水含量跃增,地面将会出现强降水;一般降水增强之前云顶抬升,光学厚度增大;若云顶高但光学厚度较小时,地面降水一般不明显,光学厚度与降水的关系更密切;对流云团合并初期,云底由小粒子组成,T-re图上表现为深厚的凝结增长区域,合并时整层云粒子的有效半径增长明显,粒子相态达到混合相态区和冻结层的温度不断升高。 相似文献