ABSTRACT

This paper investigates climate change impacts on the hydrology and water quality of Brazilian semi-arid reservoirs. An integrated approach coupling climate, hydrological and water quality models was proposed. Five general circulation models (GCMs) and two future scenarios (SSP2-4.5 and SSP5-8.5) were used for the projections. The simulations showed that uncertainty in climate forecast significantly impacted hydrological and water quality outputs. Some scenarios revealed a strong decrease in streamflow and storage volume. On the other hand, 40% of multi-GCM projections indicated reservoir eutrophication. The impacts on hydrology and water quality under SSP5-8.5 were more significant than those under SSP2-4.5. The results also indicated that drought events may be prolonged under climate change, principally at the end of the 21st century for SSP5-8.5, and may significantly increase the total phosphorus concentration. This suggests that tropical semi-arid reservoirs could be more vulnerable to eutrophication in scenarios of climate change than those in other regions.

摘要

本文研究了气候变化对巴西半干旱水库水文和水质的影响。提出了一种耦合气候、水文和水质模型的综合方法。预测使用了五个大环流模型 (GCM) 和两个未来情景（SSP2-4.5 和 SSP5-8.5）。模拟结果表明，气候预测的不确定性显着影响了水文和水质输出。一些情景显示流量和存储量大幅下降。另一方面，40% 的多 GCM 预测表明水库富营养化。SSP5-8.5对水文和水质的影响比SSP2-4.5更显着。结果还表明，干旱事件在气候变化下可能会延长，主要是在 SSP5-8 的 21 世纪末。5、并可能显着增加总磷浓度。这表明热带半干旱水库在气候变化情景下可能比其他地区更容易受到富营养化的影响。