气候变化领域集成服务门户(CCPortal): Respective Advantages of “Top-Down” Based GPM IMERG and “Bottom-Up” Based SM2RAIN-ASCAT Precipitation Products Over the Tibetan Plateau

CCPortal

DOI	10.1029/2020JD033946
	Respective Advantages of “Top-Down” Based GPM IMERG and “Bottom-Up” Based SM2RAIN-ASCAT Precipitation Products Over the Tibetan Plateau
	Fan Y.; Ma Z.; Ma Y.; Ma W.; Xie Z.; Ding L.; Han Y.; Hu W.; Su R.
发表日期	2021
ISSN	2169897X
卷号	126 期号:7
英文摘要	The Tibetan Plateau (TP) is characterized by complex topography and heterogeneous surface cover, which makes it difficult to obtain accurate precipitation data at a regional scale. Therefore, it is important to use dense ground observations to evaluate satellite-derived precipitation products. In this study, the top-down-based Global Precipitation Measurement Integrated MultisatellitE Retrievals (GPM IMERG) and bottom-up-based Soil Moisture TO RAIN-Advanced SCATterometer (SM2RAIN-ASCAT; SM2RASC) precipitation products were evaluated against 1,584 unevenly distributed rain gauges over the TP from May to October 2015. Results show: (1) The overall performances of IMERG and SM2RASC are comparable at the daily scale, with a higher correlation coefficient (CC) for IMERG and lower root-mean-square error (RMSE) for SM2RASC. Regarding the precipitation detectability, IMERG outperforms SM2RASC; (2) Spatially, SM2RASC shows better performance than IMERG in grasslands, but IMERG outperforms SM2RASC in forest areas, due to the low quality of the soil moisture retrieved by satellite in the areas; (3) The accuracy of both SM2RASC and IMERG is closely correlated with altitude and rainfall intensity. The SM2RASC product estimates light to moderate rainfall (5–25 mm/day) more accurately than the IMERG, but the IMERG product shows better performance for drizzle and heavy rainfall (>25 mm/day). Due to relatively frequent fluctuations of the ASCAT soil moisture product, SM2RASC frequently reports false rainfall in dry conditions. This study demonstrates the good performance of the SM2RASC product over the TP and suggests that the impact of vegetation density and topography should be considered for improving the SM2RAIN algorithm. © 2021. American Geophysical Union. All Rights Reserved.
英文关键词	IMERG; rainfall; SM2RAIN-ASCAT; Tibetan Plateau
语种	英语
来源期刊	Journal of Geophysical Research: Atmospheres
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/185358
作者单位	Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China; University of Chinese Academy of Sciences, Beijing, China; School of Earth and Space Sciences, Institute of Remote Sensing and Geographical Information System, Peking University, Beijing, China; Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing, China; College of Big Data and Information Engineering, Guizhou University, Guiyang, China
推荐引用方式 GB/T 7714	Fan Y.,Ma Z.,Ma Y.,等. Respective Advantages of “Top-Down” Based GPM IMERG and “Bottom-Up” Based SM2RAIN-ASCAT Precipitation Products Over the Tibetan Plateau[J],2021,126(7).
APA	Fan Y..,Ma Z..,Ma Y..,Ma W..,Xie Z..,...&Su R..(2021).Respective Advantages of “Top-Down” Based GPM IMERG and “Bottom-Up” Based SM2RAIN-ASCAT Precipitation Products Over the Tibetan Plateau.Journal of Geophysical Research: Atmospheres,126(7).
MLA	Fan Y.,et al."Respective Advantages of “Top-Down” Based GPM IMERG and “Bottom-Up” Based SM2RAIN-ASCAT Precipitation Products Over the Tibetan Plateau".Journal of Geophysical Research: Atmospheres 126.7(2021).