SSP“双碳”路径下赣江流域径流变化趋势

根据共享社会经济情景（SSPs）分为“双碳”路径（SSP1-1.9、SSP1-2.6、SSP2-4.5、SSP4-3.4、SSP4-6.0）和“高碳”路径（SSP3-7.0、SSP5-8.5)。在碳达峰（2028—2032年）和碳中和（2058—2062年）两个时期,采用5个气候模式,7个情景驱动SWAT水文模型,分析赣江流域径流演变特征,主要结论如下：1961—2017年赣江流域观测到的年均气温以0.17℃/(10 a)的速率呈显著上升趋势（p<0.01),降水以17 mm/(10 a)的速率呈不显著上升。“双碳”和“高碳”路径下,2021—2100年赣江流域均呈现暖湿态,气温持续变暖,降水有所增加;碳达峰、碳中和时期,“双碳”路径下年径流呈现增加趋势;“双碳”路径下,月径流在汛期呈现增加趋势,枯水期在SSP1-1.9、SSP1-2.6、SSP2-4.5、SSP4-3.4下呈现增加趋势,在SSP4-6.0下呈现减少趋势。“双碳”路径下极端水文事件强度将可能小于“高碳”路径。

Runoff variation trend of Ganjiang River basin under SSP “Double Carbon” path

According to the target and the peak time of carbon emissions under SSPs scenarios, SSPs were divided into “double carbon” pathway (SSP1-1.9, SSP1-2.6, SSP2-4.5, SSP4-3.4, SSP4-6.0) and “high carbon” pathway (SSP3-7.0, SSP5-8.5). The runoff evolution characteristics of Ganjiang River basin were analyzed in two periods of peak carbon dioxide emissions (2028-2032) and carbon neutral (2058-2062) based on the SWAT hydrological model. The results are as follows. (1) Annual mean temperature in the Ganjiang River basin from 1961 to 2017 showed a significant upward trend with a rate of 0.17℃/(10 a), while the precipitation increase slightly with a rate of 17 mm/(10 a). Under the “double carbon” and “high carbon” pathways, the Ganjiang River basin will be in a warm and wet state from 2021 to 2100, with temperature rising and precipitation increasing. (2) In the periods of peak carbon dioxide emissions and carbon neutral, annual runoff shows increasing tendency during “double carbon” pathway. In “double carbon” pathway, monthly runoff shows increasing tendency in all scenarios in flood season, while increasing tendency in SSP1-1.9, SSP1-2.6, SSP2-4.5, SSP4-3.4 and decreasing tendency in SSP4-6.0 in dry season. The intensity of extreme hydrological events under the “double carbon” pathway will be less than under the “high carbon” pathways.