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21.
Xuefen ZHANG Liangxu LI Rongkang YANG Ran GUO Xia SUN Jianping LUO Hongbin CHEN Daxin LIU Kebing TANG Wenwu PENG Xiaodong HAN Qiyun GUO Xiaoxia LI Xikun FEI 《大气科学进展》2021,38(4):531-537
In collaboration with 12 other institutions, the Meteorological Observation Center of the China Meteorological Administration undertook a comprehensive marine observation experiment in the South China Sea using the Yilong-10 high-altitude large unmanned aerial vehicle(UAV). The Yilong-10 UAV carried a self-developed dropsonde system and a millimeter-wave cloud radar system. In addition, a solar-powered unmanned surface vessel and two drifting buoys were used. The experiment was further supported by an intelligent, reciprocating horizontal drifting radiosonde system that was deployed from the Sansha Meteorological Observing Station, with the intent of producing a stereoscopic observation over the South China Sea. Comprehensive three-dimensional observations were collected using the system from 31 July to2 August, 2020. This information was used to investigate the formation and development processes of Typhoon Sinlaku(2020). The data contain measurements of 21 oceanic and meteorological parameters acquired by the five devices, along with video footage from the UAV. The data proved very helpful in determining the actual location and intensity of Typhoon Sinlaku(2020). The experiment demonstrates the feasibility of using a high-altitude, large UAV to fill in the gaps between operational meteorological observations of marine areas and typhoons near China, and marks a milestone for the use of such data for analyzing the structure and impact of a typhoon in the South China Sea. It also demonstrates the potential for establishing operational UAV meteorological observing systems in the future, and the assimilation of such data into numerical weather prediction models. 相似文献
22.
国产GTS1探空仪与VAISALA公司RS92探空仪对比分析 总被引:7,自引:1,他引:7
文章从静态指标与动态对比两个方面,对中国国产GTS1探空仪与芬兰Vaisala公司RS92探空仪的综合性能进行对比.对比结果表明,GTS1探空仪温度存在滞后误差,RS92探空仪湿度测量结果明显好于GTS1探空仪,200hPa以上RS92探空仪气压变化低于GTS1探空仪,测风精度方面RS92探空仪高于GTS1探空仪,850hPa以下和150hPa以上GTS1探空仪测风与RS92探空仪存在1m·s-1以内的系统差,RS92探空仪在整体性能上高于GTS1探空仪. 相似文献
23.
通过对青藏高原东部地区近几年部分探空资料的分析,得出了一些有意义的结论。结果表明:冬季,青藏高原东侧地区在对流层下部存在明显的逆温现象,在逆温层之下,大气相对湿度大,水汽随高度减小的幅度小,大气处于中性层结状况;在此逆温层之上,大气相对湿度小。在逆温层底部有大量的水汽堆积,在空中形成明显的逆湿层,而在高原主体上并没有此逆温层的存在,高原东侧各站逆温层底的高度差别不大。夏季,青藏高原东侧地区20时可以存在明显的混合层,混合层的高度在成都站最小,重庆站最大,而高原主体混合层高度大于东侧地区。旱年混合层高度大于涝年。8时和20时,冬季大气温、湿垂直特性变化不明显,而夏季具有明显的变化。夏季,降水过程明显抑制混合层的发展,在暴雨过程及其前后,混合层有明显的成熟、消亡、重新建立的特征。 相似文献
24.
25.
Electrical resistivity surveys to delineate groundwater potential aquifers in Peddavanka watershed,Anantapur District,Andhra Pradesh,India 总被引:1,自引:0,他引:1
Vertical electrical resistivity soundings were conducted in order to delineate groundwater potential aquifers in Peddavanka watershed, which is a catchment of about 398 km2 in Anantapur District, Andhra Pradesh, India. The main lithologic units in the watershed are quartzite, limestone, shale, and alluvium. Ninety-nine vertical electrical soundings were conducted using the Schlumberger configuration, covering the entire watershed. The data were interpreted with the help of master curves and auxiliary point charts. Interpretations of VES were used to generate a top layer apparent resistivity contour map and longitudinal conductance map. Isoresistivity contour maps were prepared and interpreted in terms of resistivity and thickness of various sub-surface layers using computer software (SURFER), and isocontour diagrams depicting the depth to bedrock were prepared. Resistivity results were correlated with the existing lithology. Based on the depth to bedrock, the thickness of the saturated layer and the resistivity of the second layer, a groundwater potential map has been prepared, in which good, moderate, and poor zones are classified. The study reveals that the weathered and fractured portions in shale and limestone that occur in the southernmost and central portions of the watershed area constitute the productive water-bearing zones categorized as good groundwater potential aquifers. 相似文献
26.
利用1971—2001年探空资料以及ERA-40和NCEP/NCAR再分析资料分别得到地面到300 hPa我国大陆上空大气柱水汽含量,对3种不同资料所得的柱水汽含量的空间分布特征以及线性趋势进行对比分析。结果表明:3种资料得到的柱水汽含量年平均和季节平均的空间分布特征一致;3种资料年平均的线性变化趋势在东北地区、内蒙古东部地区,西南地区北部、华南沿海和新疆北部地区均呈增加趋势;在华北和华东的部分地区,ERA-40和NCEP/NCAR再分析资料为降低趋势,而探空资料得到的柱水汽含量变化相对较小,但未通过信度检验;探空资料得到的柱水汽含量的相对变化显示我国东北地区、内蒙古东部地区、新疆地区的增加更显著。 相似文献
27.
采用EFAST方法和SCE-UA算法优化WheatSM模型参数,采用区域模拟和单站插值的方法对2013—2017年鹤壁市冬小麦各发育期日数和产量进行模拟修订,为WheatSM作物模型在豫北地区的业务应用提供参考。研究发现:区域模拟方法对鹤壁地区冬小麦生育期开始日期的模拟效果除出苗期、越冬期的外,其他均好于单点插值方法的。单点插值方法对越冬期的模拟效果明显好于区域模拟方法的。冬小麦产量的模拟效果区域模拟方法也比单点插值方法好,但两种结果的相对误差均较大。通过对WheatSM模型得到的冬小麦气象产量模拟结果进行修订,可以明显提高模型产量模拟结果。2013—2017年鹤壁地区模拟产量的误差为-17. 92%~-2. 98%,RMSE为1114. 9 kg/hm~2,NMSE为12. 59,模拟效果较好。利用区域模拟方法可以对区域内单个站点的冬小麦生长发育和产量进行模拟,但对越冬期开始时间的模拟需要参考单点插值方法的相应结果。 相似文献
28.
地表温度是衡量地表水热平衡的关键参数,微波地表温度因其范围大、全天候等独特的优势,在气候、农业和环境等领域得到广泛应用。基于经质量控制的MODIS地表温度产品对风云三号卫星C星的微波地表温度日产品和月平均产品进行验证评估,结果显示:FY-3C卫星升轨(夜晚)和降轨(白天)微波地表温度日产品平均分别高估8. 7 K、低估13. 2 K,月平均产品平均分别高估7. 9 K、低估12. 0 K,日产品和月平均产品的反演误差都在15K以内。在全球空间分布上,升轨(夜晚)和降轨(白天)月产品误差分别呈现高估和低估,热带雨林区和沙漠、荒漠区域在夜晚分别高估5 K以内和30 K以内,白天则分别低估10 K以内和10~30 K。不同土地覆盖类型间FY-3C微波地表温度反演精度存在差异,总体上升轨(夜晚)比降轨(白天)的精度高,反演精度最高和最低的土地类型分别是常绿阔叶林和荒漠、稀疏植被,不同土地覆盖类型间的地表温度反演精度在季节上存在明显差异。根据分析结果,改进FY-3C微波地表温度的反演算法,可进一步提高微波地表温度的反演精度。 相似文献
29.
This paper presents an integrated measurement technique based on DC methods (vertical electrical sounding, electrical resistivity tomography) which was used to identify faults and determine their geoelectric parameters in the western part of the Chuya basin. New information on the structure of the Chagan River valley located in the zone of the disastrous 27 September 2003 Chuya earthquake has been obtained from the results of these methods. Geoelectric cross-sections of the sedimentary sequence and the upper part of the basement were obtained from VES data, showing the block structure of the study area. Electrical resistivity tomography sections confirm the presence of a major fault between basement blocks of different heights and indicate the presence of faults bounding the valley on its right side and in the southwestern part. 相似文献
30.
This publication is a contribution to discussion on the geometry and petrography of the rock complex responsible for the Carpathian
conductivity anomaly. We analysed arguments showing that this anomaly is caused by induction in the sedimentary basin, and
make a critical review of various data to find out whether the good conductivity is connected with a rock complex containing
graphite or mineralized water. We conclude that a more likely mechanism is the ionic one, i.e., the existence of fluids, although
a final decision can only be made on the basis of deep drillings. 相似文献