Chinese Geographical Science ›› 2021, Vol. 31 ›› Issue (3): 474-490.doi: 10.1007/s11769-021-1205-9

• Articles • Previous Articles    

Evaluation of Precipitation Datasets from TRMM Satellite and Downscaled Reanalysis Products with Bias-correction in Middle Qilian Mountain, China

ZHANG Lanhui1, HE Chansheng1,2, TIAN Wei1, ZHU Yi1   

  1. 1. Key Laboratory of West China’s Environmental System (Ministry of Education), College of Earth and Environmental Sciences, Lanzhou University, Lanzhou 730000, China;
    2. Department of Geography, Western Michigan University, Kalamazoo Michigan 49008, USA
  • Received:2020-07-01 Published:2021-04-29
  • Contact: ZHANG Lanhui, HE Chansheng;
  • Supported by:
    Under the auspices of National Natural Science Foundation of China (No. 42030501, 41877148, 41501016, 41530752), Scherer Endowment Fund of Department of Geography, Western Michigan University and the Fundamental Research Funds for the Central Universities (No. lzujbky-2019-98)

Abstract: Accurate estimates of precipitation are fundamental for hydrometeorological and ecohydrological studies, but are more difficult in high mountainous areas because of the high elevation and complex terrain. This study compares and evaluates two kinds of precipitation datasets, the reanalysis product downscaled by the Weather Research and Forecasting (WRF) output, and the satellite product, the Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis (TMPA) product, as well as their bias-corrected datasets in the Middle Qilian Mountain in Northwest China. Results show that the WRF output with finer resolution performs well in both estimating precipitation and hydrological simulation, while the TMPA product is unreliable in high mountainous areas. Moreover, bias-corrected WRF output also performs better than bias-corrected TMPA product. Combined with the previous studies, atmospheric reanalysis datasets are more suitable than the satellite products in high mountainous areas. Climate is more important than altitude for the ‘falseAlarms’ events of the TRMM product. Designed to focus on the tropical areas, the TMPA product mistakes certain meteorological situations for precipitation in subhumid and semiarid areas, thus causing significant ‘falseAlarms’ events and leading to significant overestimations and unreliable performance. Simple linear bias correction method, only removing systematical errors, can significantly improves the accuracy of both the WRF output and the TMPA product in arid high mountainous areas with data scarcity. Evaluated by hydrological simulations, the bias-corrected WRF output is more reliable than the gauge dataset. Thus, data merging of the WRF output and gauge observations would provide more reliable precipitation estimations in arid high mountainous areas.

Key words: evaluation, Weather Research and Forecasting (WRF), Tropical Rainfall Measuring Mission (TRMM), precipitation, bias correction, high mountainous areas