Evaluation of multiple forcing data sets for precipitation and shortwave radiation over major land areas of China

Abstract

Abstract. Precipitation and shortwave radiation play important roles in climatic, hydrological and biogeochemical cycles. Several global and regional forcing data sets currently provide historical estimates of these two variables over China, including the Global Land Data Assimilation System (GLDAS), the China Meteorological Administration (CMA) Land Data Assimilation System (CLDAS) and the China Meteorological Forcing Dataset (CMFD). The CN05.1 precipitation data set, a gridded analysis based on CMA gauge observations, also provides high-resolution historical precipitation data for China. In this study, we present an intercomparison of precipitation and shortwave radiation data from CN05.1, CMFD, CLDAS and GLDAS during [2008][2009][2010][2011][2012][2013][2014]. We also validate all four data sets against independent ground station observations. All four forcing data sets capture the spatial distribution of precipitation over major land areas of China, although CLDAS indicates smaller annual-mean precipitation amounts than CN05.1, CMFD or GLDAS. Time series of precipitation anomalies are largely consistent among the data sets, except for a sudden decrease in CMFD after August 2014. All forcing data indicate greater temporal variations relative to the mean in dry regions than in wet regions. Validation against independent precipitation observations provided by the Ministry of Water Resources (MWR) in the middle and lower reaches of the Yangtze River indicates that CLDAS provides the most realistic estimates of spatiotemporal variability in precipitation in this region. CMFD also performs well with respect to annual mean precipitation, while GLDAS fails to accurately capture much of the spatiotemporal variability and CN05.1 contains significant high biases relative to the MWR observations. Estimates of shortwave radiation from CMFD are largely consistent with station observations, while CLDAS and GLDAS greatly overestimate shortwave radiation. All three forcing data sets capture the key features of the spatial distribution, but estimates from CLDAS and GLDAS are systematically higher than those from CMFD over most of mainland China. Based on our evaluation metrics, CLDAS slightly outperforms GLDAS. CLDAS is also closer than GLDAS to CMFD with respect to temporal variations in shortwave radiation anomalies, with substantial differences among the time series. Differences in temporal variations are especially pronounced south of 34 • N. Our findings provide valuable guidance for a variety of stakeholders, including land-surface modelers and data providers.

Assessment of Satellite-Derived Precipitation Products for the Beijing Region

“…The performance of the CMFD and 3B42 calibrated datasets were better than the CMORPH and 3B42-RT datasets at monthly and yearly scales. The 3B42 calibrated dataset was integrated into the CMFD dataset as the background field for the precipitation analysis, which means the occurrence of a precipitation event in the CMFD product was determined by the 3B42 calibrated dataset, however, the 3B42 calibrated dataset provides relative few data north of 40 • N. The GLDAS precipitation dataset was used as the background field in this region [57,58]. The performance of CMFD was better than the 3B42 calibrated data, which may be attributed to the performance of the GLDAS dataset and the integration of the conventional meteorological observations from the China Meteorological Administration into the CMFD dataset.…”

Establishment and Evaluation of the China Meteorological Assimilation Driving Datasets for the SWAT Model (CMADS)

“…Precipitation data of CMADS were stitched using CMORPH's global precipitation products [23], the National Meteorological Information Center's data of China (which is based on CMORPH's integrated precipitation products) [24]. The latter contains daily precipitation records observed at 2400 national meteorological stations and the CMORPH satellite's inversion precipitation products.…”

“…Since prior studies on precipitation and solar radiation exist [24,25,27], further verification of these elements was not performed in this study. This section describes the verification that was performed for the remaining four elements (namely, air temperature, surface pressure, relative humidity, and wind speed) to test their applicability to China.…”

Evaluations and Improvements of GLDAS2.0 and GLDAS2.1 Forcing Data's Applicability for Basin Scale Hydrological Simulations in the Tibetan Plateau

“…CMFD was developed by the Institute of Tibetan Plateau Research, Chinese Academy of Sciences. CMFD is based on China Meteorological Administration station measurements (He & Yang, ) and has been implemented in many studies showing general good performance (Xue et al, ; Yang et al, ; Zhou et al, ).…”

“…Understanding uncertainty and investigating possible improvements are two key issues in GLDAS data applications. Many studies have evaluated GLDAS1.0, and uncertainty correction approaches have been developed (Bai et al, ; Chen et al, ; Huang et al, ; Kato et al, ; Qi et al, ; Wang et al, , ; Yang et al, ; Zaitchik et al, ; Zhou et al, ). For example, Gottschalck et al () investigated combinations of GLDAS1.0 forcing data with four precipitation products seeking an optimal combination.…”