Detecting the quantitative hydrological response to changes in climate and human activities.

Area of Science:

• Hydrology
• Climate Science
• Environmental Management

Background:

• Sustainable regional water resource management requires understanding drivers of runoff change.
• Differentiating impacts of climate change and human activities on water resources is crucial.

Purpose of the Study:

• To systematically review and compare ten quantitative methods for attributing runoff changes.
• To apply these methods to the Yanhe River basin to assess climate change and human activity impacts.

Main Methods:

• Systematic review of empirical statistics, elasticity-based methods, and hydrological modeling.
• Comparative analysis of ten quantitative methods using the Yanhe River basin case study.

Main Results:

• Climate change was the dominant driver of runoff decline in the Yanhe River basin (54.1% on average).
• Human activities contributed significantly (45.9% on average) to the observed decrease.
• Hydrological modeling and elasticity-based methods yielded consistent results, unlike empirical statistics.

Conclusions:

• Climate change is the primary factor influencing runoff reduction in the Yanhe River basin.
• Empirical statistics methods proved unsuitable for this specific case study.
• Methodological choice significantly affects attribution results, necessitating careful consideration of applicable conditions.