Precipitation Estimation with Parameterized GIS Modules for Catchments in Gansu Province, P. R. China
This paper estimated catchment precipitations for Gansu Province, PRC, with both geostatistical analysis, GIS general modules and their parameterizations. With statistics, perspective view and schemes of the results,comparison was made on their potentiality to depict spatial distribution characteristics of precipitation, effected by main factors especially the facets and elevations of huge mountainous regions. It is a compelling case study on GIS interpolations with IDW, Kriging and Spline modules and parameterizations on them to achieve a better precision in validation test based on scarce meteorological and the more hydrological gauging records. Effects of elevation differences between facets of the TIN generated from elevations of meteorological stations and the DEM representing actual relief, the vertical changing rates of precipitation, and the maximum and minimum precipitation heights for each catchment were emphasized respectively. It showed that parameterized estimations can approach a similar precision to that with more hydrological gauging records; for this particular region, and is moderate and reasonable, while the point-averaged statistics of the only meteorological station data is over-estimated, and the interpolation of the GIS general methods without parameterization is under-estimated. It is concluded that parameterization on GIS modules especially the Krigings could effectively generate areal estimates which is more reliable in featuring spatial variations of precipitation. An appropriate database for a variety of catchment characteristics will be more beneficial to hydrological modeling and ecological studies than other methods ever shown.
precipitation estimation catchments parameterized GIS modules
Jiguo Zhen Quan-gong Chen Tao Han
Terrestrial Resources Planning & Research, Lanzhou;730000 P.R.China;College of Pastoral Agricultural College of Pastoral Agricultural Science and Technology Lanzhou University, Lanzhou,730000 P.R.China Key Laboratory of Arid Climatic Change and Reducing Disaster, Institute of Arid Meteorology, CMA,Lan
国际会议
北京国际地理信息系统学术讨论会第七届会议（7th International Workshop Geographical Information System
北京
英文
467-477
2007-09-14（万方平台首次上网日期，不代表论文的发表时间）