Abstract. Though extensive researches were conducted in the source region of the Yellow
River (SRYR) to analyse climate change influence on streamflow, however, few
researches concentrate on streamflow of the sub-basin above the Huangheyan
station in the SRYR (HSRYR) where a water retaining dam was built in the
outlet in 1999. To improve the reservoir regulation strategies, this study
analysed streamflow change of the HSRYR in a mesoscale. A tank model (TM) was
proposed and calibrated with monthly observation streamflow from 1991 to
1998. In the validation period, though there is a simulation deviation during
the water storage and power generation period, simulated streamflow agrees
favourably with observation data from 2008 to 2013. The model was further
validated by two inside lakes area obtained from Landsat 5, 7, 8 datasets
from 2000 to 2014, and significant correlations were found between the
simulated lake outlet runoff and respective lake area. Then 21 Global Climate
Models (GCM) ensembled data of three emission scenarios (SRA2, SRA1B and
SRB1) were downscaled and used as input to the TM to simulate the runoff
change of three benchmark periods 2011–2030 (2020s), 2046–2065 (2050s),
2080–2099 (2090s), respectively. Though temperature increase dramatically,
these projected results similarly indicated that streamflow shows an increase
trend in the long term. Runoff increase is mainly caused by increasing
precipitation and decreasing evaporation. Water resources distribution is
projected to change from summer-autumn dominant to autumn winter dominant.
Annual lowest runoff will occur in May caused by earlier snow melting and
increasing evaporation in March. According to the obtained results, winter
runoff should be artificially stored by reservoir regulation in the future to
prevent zero-flow occurrent in May. This research is helpful for water
resources management and provides a better understand of streamflow change
caused by climate change in the future.
Can Reservoir Regulation Along the Yellow River Be a Sustainable Way to Save a Sinking Delta?
