Assessing the climate forecast system reanalysis weather data driven hydrological model for the Yangtze river basin in China

Abstract

It is a challenge to adequately represent meteorological data for river basin modelling in data-scarce regions. Hydrological models may benefit from alternative climate data sources such as the Climate Forecast System Reanalysis (CFSR) weather data. A proposed method was applied to evaluate the applicability of CFSR data in the Soil and Water Assessment Tool (SWAT) eco-hydrological model for the 1.8×106 km2 Yangtze River Basin (YRB) in China. The CFSR data were first validated by ground-based meteorological station (GMS) data to confirm sufficient accuracy to predict the hydrology for the YRB. It was determined that the CFSR simulation was able to generate acceptable accuracy with calibrated parameters of GMS-based model. The R2 and ENS of the monthly results from both GMS- and CFSR-SWAT simulations were > 0.70 in both calibration and validation periods. The monthly streamflow hydrograph from GMS and CFSR simulations showed two different patterns: distinct differences in baseflow and less discrepancy for the peak flows, such as the patterns at Cuntan and Yichang gauge stations, whereas the results are characterized as close matches the peaks and the recession periods at Hankou and Datong gauge stations. The CFSR simulation generated better results in the middle and lower reaches than in the upper reach of the basin. To a certain extent, the CFSR provides an alternative to quickly build hydrological model in data scarce area for large basins.