Search

The central and western Tibetan Plateau (CWTP) is characterized by harsh environment and strong interactions among the spheres of earth as well as significant changes in climate and water cycles over the past four decades. The lack of precipitation observations is a bottleneck for the study of land surface processes in this region. Over the past six years, we have designed and established two observation transects across the south-north and the west-east in this region to obtain hourly rainfall data during the warm season (May–September). The south-north transect extends from Yadong Valley on the southern slope of the Himalayas to Shuanghu County in the hinterland of the plateau, with a total of 31 stations; the west-east transect extends from Shiquanhe in the west to Naqu in the central TP, with a total of 22 stations. The observation dataset has been applied to clarify the spatiotemporal characteristics of precipitation in the CWTP, to evaluate the quality of typical gridded precipitation products, to support the development of regional climate models, and to reveal the processes of summertime lake-air interactions. The observation dataset has been released in the National Tibetan Plateau Data Center. [ABSTRACT FROM AUTHOR]

Satellite precipitation products can provide alternative data in remote areas with sparse surface observations, but the performance of these products must be evaluated before hydrometeorological applications. The western Tibetan Plateau (WTP) covers an area of nearly 1,500,000 km2, where China Meteorological Administration stations are very sparse due to the harsh natural environment. Therefore, previous evaluations of satellite precipitation products have resulted in a gap on the WTP. In this study, hourly data collected from 29 newly established rain gauges on the WTP were applied to evaluate the performance of four Global Precipitation Measurement (GPM)-Era precipitation products without calibration (IMERG-UC and GSMaP-MVK) and with calibration (IMERG-C and GSMaP-Gauge). The evaluation results for the WTP were compared with those for the eastern Tibetan Plateau (ETP). (1) The effect of the calibration of satellite products highly depends on the temporal resolution of precipitation data used for calibration. The GSMaP-Gauge, which are calibrated with daily data, outperforms the IMERG-C, which are calibrated with monthly data, on both monthly scale and daily scale. (2) The calibration effect of the satellite products is not positive in reproducing the precipitation amount on the WTP due to few observations available for calibration but was notable on the ETP. (3) None of the four satellite precipitation products can reproduce the hourly precipitation frequency-intensity structure well. Both IMERG and GSMaP produce too much light precipitation events on the WTP. In addition, the four products produce too early timing of diurnal precipitation peak on the WTP. The calibration does not improve the timing phase of precipitation amount but affects the intensity of diurnal precipitation peaks on the WTP. These new findings provide important information on the accuracy of the four widely used satellite precipitation products on the WTP and thus can be a solid reference for hydrometeorological applications on the WTP. • The GPM-Era precipitation products were evaluated for the first time on the western Tibetan Plateau (WTP) based on hourly data from 29 newly established gauges. • The calibration of the satellite products is not positive on the WTP, where few observations are available. • None four satellite products well reproduce hourly frequency-intensity structure and diurnal peaks of precipitation on WTP. [ABSTRACT FROM AUTHOR]