Evaluation of multisource precipitation input for hydrological modeling
in an alpine basin: a case study from the Yellow River Source Region
(China)
Abstract
Alpine basins are essential to the conservation of water resources.
However, they are typically poorly gauged and inaccessible, owing to the
harsh prevailing environment and complex terrain. To investigate the
influences of different precipitation inputs on hydrological modeling in
alpine basins, two representative satellite precipitation products
[Tropical Rainfall Measuring Mission (TRMM) and Integrated
Multi-Satellite Retrievals for GPM (IMERG)] and two reanalysis
precipitation products [China Meteorological Assimilation Driving
Datasets for the SWAT model (CMADS) and Climate Forecast System
Reanalysis (CFSR)] in the Yellow River Source Region (YRSR) were
selected for evaluation and hydrological verification against
gauge-observed data (GO). Results indicates that the accuracy of these
precipitation products in the warm season is higher than that in the
cold season, and IMERG has the best performance, followed by CMADS,
CFSR, and TRMM. TRMM seriously overestimates high rainfall of greater
than 10 mm/day. CFSR overestimates moderate precipitation events of
1–10 mm/d, while CMADS underestimates the effects of precipitation
events of 1–20 mm/d. Models using the GO as input yielded satisfactory
performance during 2008–2013, and precipitation products have poor
simulation results. Although the model using IMERG as input yielded
unsatisfactory performance during 2014–2016, this did not affect the
use of IMERG as a potential data source for YRSR. After bias correction,
the quality of CFSR improves significantly with R2 and NSE increasing by
0.25 and 0.31 at Tangnaihai station, respectively. Model driven by the
combination of GO and CMADS precipitation performed the best in all
scenarios (R2 = 0.77, NSE = 0.72 at Tangnaihai station; R2 = 0.53, NSE =
0.48 at Jimai station). These results can provide reference data, and
research ideas, for improved hydrological modeling of alpine basins.