Attribution mechanism of drought propagation time with changes in climate and underlying surface

Abstract

Study region: Thirteen catchment regions of the Yellow River basin, located in northern China. Study focus: Drought is a natural phenomenon characterized by a water deficiency that impacts various aspects of the hydrological cycle. Water deficit signals propagate through the hydrological system and are manifested in the sequential occurrence of meteorological drought, agricultural drought, and hydrological drought. The climate and underlying surface continuously influence the propagation of drought. Hence, it is imperative to investigate the attribution mechanism of drought propagation under the influence of climate and underlying surface. New hydrological insights for the region: This study provides a theoretical attribution analysis framework for drought propagation time, including statistical and physical mechanisms. From the point of view of statistical analysis, this study found that the difference between meteorological drought and hydrological drought trend statistics was significantly correlated with the propagation time. And from the analyses of the water-energy coupled equation show that the contribution of climate and underlying surface to runoff was significantly correlated with the propagation time. From the point of view of physical mechanisms, hydrometeorological and underlying surface factors are important variables affecting drought propagation time, and the results of regression analyses provide empirical formulas for drought propagation time. Unlike previous studies, this study delved into the attribution mechanism of drought propagation time through regional comparisons. These findings are expected to be helpful for local drought management efforts and mitigation of associated losses.

Keywords

• Propagation time
• Attribution mechanism
• Water-energy coupled equation