摘要
出于提高基于数值模拟的风资源评估精度的目的,本文对NASA发布的3秒分辨率(90m)SRTM(shuttleradar topography mission,航天飞机雷达地形测绘任务)数据,根据SRTM缺测区域的特点利用直接赋值和双线性多项式内插结合的方法进行填补,并将填补后的SRTM数据作为下垫面的地形高度资料,引入中尺度大气模式MM5中,以研究可提高模拟精度的方法。本文以广东省以及邻近省份地区和近海海域为例,模拟了2002年4月和11月各两天的4个嵌套区域(分别为27km9、km、3km和1km分辨率)的逐时风场,通过与利用USGS地形数据的对比试验,分析了SRTM对近地层风场模拟结果的影响。试验结果表明:与USGS地形数据相比,SRTM数据更接近于真实地形。MM5模式引入SRTM数据后,模拟精度有所提高。地形的变化对风向影响比较明显,但地形的变化引起单点风速的变化情况及其原因比较复杂,有待于进一步研究。
With the development of the commercial wind industry, mesoscale atmospheric models such as MM5 are becoming more widely used in wind resource assessment and wind farm siting. In terms of accuracy, surface terrain is one of the most important factors in numerical modeling. This paper focuses on the integration of SRTM DEM terrain data from NASA （resolution of 3 arc-seconds） into MM5, and the accuracy of the simulation compared to using USGS terrain data GTOPO30 （resolution of 30 arc-seconds）. The effects of SRTM on numerical simulation of wind fields using MM5 were tested at four resolutions （27kin, 9kin, 3km, lkm） for Guangdong Province and parts of neighboring provinces, for the time periods of 20 - 22 April 2002 and 1 - 3 November 2002. Gaps in the SRTM DEM data for the experimental area were filled for offshore areas by assigning the value of 0, and some small mountainous areas were filled in using bilinear polynomial interpolation. The data was then re-sampled to the MM5 Grid. Two experiments were carried out which separately integrated SRTM and USGS DEM data into the simulation, while leaving other settings unchanged. Results showed that differences between SRTM and USGS DEM data were not obvious except at specific points. Using elevation data from 36 weather stations, we found that SRTM data is better than USGS terrain data at reflecting real terrain conditions. Compared with observed wind speeds, the simulation results showed that the use of SRTM DEM data can improve accuracy by about 0.2m/s, which was not a significant improvement. Different surface terrain can affect wind direction, especially in mountainous areas. However, the relationship of terrain and wind speed is not so complex, perhaps due to the terrain distribution of neighboring areas, gradients or aspect conditions.
出处
《资源科学》
CSSCI
CSCD
北大核心
2008年第5期662-666,共5页
Resources Science
基金
广东省科技计划项目:"面向风电开发的在线风能资源综合评估与分析系统"(编号:2005B10501002)
广东省科技计划项目:"广东省海上风电场选址及资源评估研究"(编号:2005B32601010)
关键词
风场模拟
数字高程模型
SRTM
MM5
广东
Numerical simulation of wind fields
DEM
SRTM
MM5
Guangdong Province
