Abstract: In line with the carbon peaking and carbon neutrality, known as the dual-carbon goal of China, we divided SSP-RCPs into the dual-carbon scenario (SSP1-1.9, SSP1-2.6, SSP2-4.5, SSP4-3.4, and SSP4-6.0) and the high-carbon scenario (SSP3-7.0, and SSP5-8.5). In the aim of offering suggestions for basin water resources management under the scenario of dual-carbon goal, we analyzed the streamflow change in Fuhe River Basin (FRB) in the near-term (2021-2040), mid-term (2041-2060) and end-term (2081-2100) in the 21st century by using SWAT hydrological model. Results demonstrate that: 1) From 1961 to 2019, the annual average temperature climbed markedly at a rate of 0.18 ℃/(10 a), while the annual precipitation dropped significantly at -32.8 mm/(10 a). 2) Under the dual-carbon scenario, the increment of annual average temperature in the FRB is projected to intensify with the passing of time compared with that in base period (1995-2014). Annual average discharge is projected to fluctuate upwardly; monthly average discharge is expected to increase from September to next February but a decline from March to July. The extreme high discharge is expected to increase while extreme low discharge decline, indicating the alleviation of hydrological extremes. 3) In high-carbon scenario, the annual average temperature is estimated to rise more significantly than that in the double-carbon scenario; but the annual precipitation would fall in the near-term and the end-term. The increment of annual average discharge is projected to be greater than that in double-carbon scenario with average temperature rising more sharply from May to October. In addition, extreme high discharges in all three periods are projected to increase.

Key words: streamflow change, temperature and precipitation change, double-carbon scenario, projection, Fuhe River Basin