Validation of the Accuracy of Different Precipitation Datasets over Tianshan Mountainous Area

Chuancheng Zhao,Shuhua Yi,Shuxia Yao,Haidong Han,Shiqiang Zhang,Qiudong Zhao

doi:10.1155/2015/617382

Abstract

Precipitation is one of the important water supplies in the arid and semiarid regions of northwestern China, playing a vital role in maintaining the fragile ecosystem. In remote mountainous area, it is difficult to obtain an accurate and reliable spatialization of the precipitation amount at the regional scale due to the inaccessibility, the sparsity of observation stations, and the complexity of relationships between precipitation and topography. Furthermore, accurate precipitation is important driven data for hydrological models to assess the water balance and water resource for hydrologists. Therefore, the use of satellite remote sensing becomes an important means over mountainous area. Precipitation datasets based on station data or pure satellite data have been increasingly available in spite of several weaknesses. This paper evaluates the usefulness of three precipitation datasets including TRMM 3B43_V6, 3B43_V7, and Asian Precipitation Highly Resolved Observational Data Integration Towards Evaluation with rain gauge data over Tianshan mountainous area where precipitation data is scarce. The results suggest that precipitation measurements only provided accurate information on a small scale, while the satellite remote sensing of precipitation had obvious advantages in basin scale or large scale especially over remote mountainous area.

Highlights

Mountainous areas play a critical role in maintaining water resource supply in the arid and semiarid regions [1, 2]
The mean annual precipitation over the Tianshan mountainous area displays a well-known pattern of more mean annual precipitation in the north than in the south and more in the west than in the east during the period 1998 to 2007
The results indicate that the two databases are well matched in the west and the middle compared with the east of Tianshan mountainous area

Summary

Introduction

Mountainous areas play a critical role in maintaining water resource supply in the arid and semiarid regions [1, 2]. Due to the inaccessibility, the sparsity of observation stations, and the complexity of relationships between precipitation and topography, little data has generally been collected in mountainous areas, and it is difficult to obtain an accurate and reliable spatialization of precipitation amount at the regional scale [3,4,5]. As one important input parameter for hydrological and ecological models, how to obtain high resolution precipitation data in remote mountainous areas is a true challenge for researchers [11, 12]. Precipitation data is mainly obtained by rain gauge measurement, estimation, and modeling. The density of rain gauge networks is seriously limited in mountainous area, and the distribution is unreasonable and even practically impossible in high mountainous area. There are always different types of error such as inherent measurement and retrieval

Methods

Results

Discussion

Conclusion