Abstract. To quantify climate change impact and difference on
basin-scale river runoff under the limiting global warming thresholds of 1.5 and 2.0 ∘C, this study examined four river basins
covering a wide hydroclimatic setting. We analyzed projected climate change
in four basins, quantified climate change impact on annual and seasonal
runoff based on the Soil Water Assessment Tool, and estimated the
uncertainty constrained by the global circulation model (GCM) structure
and the representative concentration pathways (RCPs). All statistics for the
two river basins (the Shiyang River, SYR, and the Chaobai River, CBR)
located in northern China indicated generally warmer and wetter conditions,
whereas the two river basins (the Huaihe River, HHR, and the Fujiang River, FJR) located in southern China projected less warming and were
inconsistent regarding annual precipitation change. The simulated changes in
annual runoff were complex; however, there was no shift in seasonal runoff
pattern. The 0.5 ∘C global warming difference resulted in 0.7 and 0.6 ∘C warming in basins in northern and
southern China, respectively. This led to a projected precipitation increase
by about 2 % for the four basins and to a decrease in simulated annual
runoff of 8 % and 1 % in the SYR and the HHR, respectively, but to an
increase of 4 % in the CBR and the FJR. The uncertainty in projected
annual temperature was dominated by the GCMs or the RCPs; however, that of
precipitation was constrained mainly by the GCMs. The 0.5 ∘C
difference decreased the uncertainty in the annual precipitation projection and the
annual and monthly runoff simulation.
Assessment of climate change impact and difference on the river runoff in four basins in China under 1.5 and 2.0 °C global warming
