The Vietnam Gridded Precipitation (VnGP) Dataset: Construction and Validation

Abstract

In this study, daily-observed data from 481 rain gauges were used to build a new gridded rainfall dataset for Vietnam based on the Spheremap interpolation technique. The new dataset, called Vietnam Gridded Precipitation (VnGP) Dataset has the resolution of 0.25° and covers the period 1980−2010. The validation was done for VnGP by assessing the spatial distribution, correlations, mean abosolute errors, root mean square errors with gauge observations. Results showed that VnGP had a relatively better performance compared to the datasets that used different interpolation techniques or used less number of input rain gauges. VnGP is currently available at the Data Integration and Analysis System (DIAS) managed by the

Precipitation estimation performance by Global Satellite Mapping and its dependence on wind over northern Vietnam

“…Finally, we consider the substantially higher rainfall over the coast in the GSMaP, compared to the VnGP. Nguyen-Xuan et al (2016) showed the coarse distribution of gauge stations in Vietnam and indicated that the interpolated method, Spheremap, did not always have an advantage in regions with coarse gauge networks. Price et al (2000) identified unrealistic precipitation maxima at grids between the coast and the inland gauge stations that were neighbors of grids that were without sufficient information on surface rainfall, in spatially interpolated data-and we must assume it is possible that the VnGP also had abnormally low values at grids in similar locations.…”

“…The VnGP Dataset (Nguyen-Xuan et al 2016) was used to determine heavy-rain event seasonality and to groundtruth daily precipitation data, as part of the GSMaP data performance evaluation process. The dataset was constructed using rain gauge data from 481 Vietnam Meteorological Hydrological Administration (VMHA) stations, using the Spheremap interpolation method (Willmott et al 1985), modified for spherical coordinates, and based on the weighted horizontal interpolation algorithm introduced by Shepard (1968).…”

“…The purpose of this study, therefore, is to obtain basic knowledge on satellite precipitation data, to potentially improve realtime hydrological forecasting, focusing on heavy-rain events over northern Vietnam, at a daily time scale. The GSMaP, the Vietnam Gridded Precipitation (VnGP) Dataset (Nguyen-Xuan et al 2016), produced from rain gauge measurement, and operational radiosonde data for Hanoi are utilized to investigate satellite-based precipitation estimate performance, and its dependence on wind for heavy-rain events. We also included basic analyses to elucidate features of lower-tropospheric wind, and the relationship between wind and precipitation.…”

Uncertainties of gridded precipitation observations in characterizing spatio‐temporal drought and wetness over Vietnam

“…The study by Nguyen et al . () has validated VnGP with gauge observation in terms of spatial distribution, correlation, mean absolute error, root‐mean‐square error and obtained good results. To our knowledge, the VnGP is the best precipitation observation gridded data set that is currently a good representation of gauge observations over Vietnam.…”

“…Brief descriptions of individual data sets are provided here. The most recent Vietnam-gridded precipitation data (VnGP) were constructed using 481 rain gauges over Vietnam (Nguyen et al, 2016). It was noted that among multiple interpolations tested, the Spheremap interpolation technique showed relatively better performance compared to the other methods such as the inversed distance weighting, Kriging and Cressman methods and was therefore chosen to construct the VnGP.…”