A conceptual framework for impact assessment of anthropogenic activities on drought propagation

Abstract

This research addresses a critical gap in understanding the complex relationship between anthropogenic activities and drought propagation, acknowledging the growing global concern over water scarcity. It aims to enhance the understanding of anthropogenic drivers influencing drought dynamics by proposing a conceptual framework for assessing their impacts. The proposed framework encompasses hydrological modeling using the SWAT model during both disturbed and undisturbed periods, as well as assessments of meteorological and hydrological droughts. Additionally, it includes a probabilistic analysis utilizing a copula-based approach to evaluate drought propagation probabilities and an assessment of the impacts of anthropogenic activities. The performance of the SWAT model, evaluated using Nash-Sutcliffe Efficiency (NSE) and the Coefficient of determination (R²), yielded values of 0.84 and 0.86 during calibration, and 0.81 and 0.80 during validation. Additionally, the Pettitt test, used to identify streamflow change points, indicated distinct periods of undisturbed and disturbed conditions. Analysis of the Streamflow Drought Index (SDI) revealed that 25.77% of the undisturbed period experienced mild drought, 9.39% moderate drought, and 3.13% severe drought. In contrast, the disturbed period saw 41.67% mild drought, 11.76% moderate drought, and 7.35% severe drought. Moreover, the analysis of drought propagation time revealed that anthropogenic activities significantly influenced variations in hydrological drought (HD) and meteorological drought (MD) during the propagation of HD. The undisturbed period displayed a 46% increase in meteorological drought thresholds and severity levels, while the disturbed period exhibited more substantial variations, ranging from 3% to 64%. These findings have significant real-world implications, highlighting that anthropogenic activities intensify drought risks and alter the natural patterns of drought propagation. Overall, the insights gained from this study can support the development of evidence-based policies and adaptive management practices that enhance drought preparedness and resilience in regions vulnerable to water scarcity.