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981.
为了更好地认识季风对南海南部海洋环境变化和生态系统变化的影响,在马来西亚的Bachok海洋站设计、安装了一种轻便型、耐腐蚀的海岸带自动气象站系统。该系统自动采集气温、气压、风速和风向、相对湿度、降水、太阳短波辐射和长波辐射共7个气象要素,将数据存入CF卡并通过串口主动上传至上位机,通过服务程序实时显示气象数据并上传气象数据至云服务器供用户下载。本系统利用实验室校准和最小二乘法的修正来保证数据质量,近一年的连续测试表明该系统的性能稳定,在2016-05纳入到全球气象观测区域站中。 相似文献
982.
983.
Observation and assessment of wind resources is a prerequisite for wind farm construction. Due to the investment cost of offshore wind farm is very expensive, more accurate assessment of wind resources is needed to reduce their investment risks. From traditional field observation to multi-platform remote sensing and from ordinary mathematical statistics to coupled numerical model simulation, abundant offshore wind data and evolving assessment methods make the results of offshore wind resource assessment more and more reliable. Poor station observations and rich remote sensing data are distinct characteristics of offshore wind data. Technology integration of applying multi-scale coupled models to assimilate multi-source remote sensing and station data is a mainstream development direction of offshore wind resource assessment methods. The wind resource assessment for offshore wind farm should focus on data quality and method selections of data interpolation, wind speed calculation of return period and wind energy parameters adjusted for a long term condition because these factors can significantly affect the operating efficiency of future wind farm. 相似文献
984.
为了了解潮流从西北太平洋经吕宋海峡进入南海内的变化及其垂向结构,本文利用在吕宋海峡附近沿东西方向布放的多套潜标同步获得的高分辨率ADCP长时间连续观测上层海流资料,使用调和分析方法将实测海流分解成3部分:不随时间变化的定常流、周期性潮流和剩余流,并将潮流分解为正压潮流和斜压潮流。通过对实测海流中各组分的分析,得到以下结论:该区域潮流类型在不同深度上有明显变化;M2潮自吕宋海峡传入南海后强度显著减弱75%左右,K1、O1分潮在上层强度减弱约三分之一。从垂向变化来看,在潮流强度上,各站点垂直方向上潮流强度均发生变化。从方向上看,各分潮潮流椭圆东西向特征明显,长轴变化较大,短轴(南北向特征)垂向变化不显著;潮流运动主要沿逆时针方向,垂直方向上潮流明显减弱或增强时会发生转向。斜压潮流主要集中在上表层,100m左右以下随深度逐渐减弱。东西方向斜压潮流能量比正压潮流强,而南北向的流比较稳定,且斜压潮流能量远小于正压潮流。定常流强度在各站点呈现相似的变化趋势,随深度变化减弱。 相似文献
985.
986.
987.
一次基于综合探测资料的山东半岛冷流暴雪特征分析 总被引:2,自引:2,他引:0
利用多普勒天气雷达、风廓线雷达、加密自动站、浮标站、常规探空和地面等多种观测资料,对2014年12月山东半岛东部一次冷流暴雪的发生、演变特征进行了分析。结果表明:(1)此次冷流暴雪发生时渤海上空500 hPa气温在-36℃左右,850 hPa气温在-18~-16℃,海面西北风12 m·s~(-1)。700 hPa以下为混合层,1000~700 hPa混合层内近乎饱和。浮标站资料显示海表面到850 hPa的较大海气温差和山东半岛较强海岸锋是产生暴雪的重要原因。(2)暴雪发生时雷达回波的PPI在30~45 dBz;每6 min雷达回波垂直剖面显示1个较强降雪回波单体持续时间可达到1h。雷达资料反演0.8 km以上风场表明:强降雪回波位于NE与NW风辐合区的东侧,冷流暴雪的水平风辐合主要在3 km以下。风廓线雷达资料表明:暴雪发生前在100m以下有弱西风存在,暴雪发生时1 50~700 m弱的西北风(6 m·s~(-1))和低层切变线辐合的共同存在,有利于降雪对流的加强;当这种弱西北风层消失后,降雪即停止。 相似文献
988.
Monitoring soil moisture with satellite sensors is an effective approach for agricultural drought assessment. Currently, large quantities of sensor-derived observation data with different observation metadata models exist, and they require efficient and accurate methods of discovery. In this study, an earth observation (EO) metadata ontology with a spatiotemporal-spectral-enhanced structure is designed to solve this problem. The ontology is based on the proposed EO metadata model, which is composed of nonfunctional and functional sub-modules and supports the Open Geospatial Consortium EO profile of observations and measurements. Using EO metadata ontology, an application for soil moisture monitoring in Hubei Province in China is tested. The results indicate that metadata retrieval with a spatiotemporal-spectral-enhanced method can efficiently achieve fine-grained discovery of qualified EO metadata and obtain soil moisture monitoring information from sensor images. In summary, the spatiotemporal-spectral semantics in the proposed ontology demonstrate the use of EO metadata in the context of a soil moisture monitoring application, improving the efficiency and accuracy of EO metadata discovery. 相似文献
989.
990.
To investigate the potential effects of aerosols on the microphysical properties of warm clouds, airborne observational data collected from 2009 to 2011 in Tongliao, Inner Mongolia, China, were statistically analyzed in this study. The results demonstrated that the vertical distribution of the aerosol number concentration(N_a) was similar to that of the clean rural continent. The average aerosol effective diameter(D_e) was maintained at approximately 0.4 μm at all levels. The data obtained during cloud penetrations showed that there was a progressive increase in the cloud droplet concentration(N_c) and liquid water content(LWC) from outside to inside the clouds, while the Nawas negatively related to the Ncand LWC at the same height. The fluctuation of the N_a, Ncand LWC during cloud penetration was more obvious under polluted conditions(Type 1) than under clean conditions(Type 2). Moreover, the wet scavenging of cloud droplets had a significant impact on the accumulation mode of aerosols, especially on particles with diameters less than 0.4 μm. The minimum wet scavenging coefficient within the cloud was close to 0.02 under Type 1 conditions, while it increased to 0.1 under Type 2 conditions,which proved that the cloud wet scavenging effect under Type 1 conditions was stronger than that under Type 2 conditions.Additionally, cloud droplet spectra under Type 1 conditions were narrower, and their horizontal distributions were more homogeneous than those under Type 2 conditions. 相似文献