Soil moisture and wind speed exacerbate the propagation from snow drought to vegetation browning

Dry and warm snow drought has a lagging effect on vegetation browning during the growing season, but has not been systematically studied. This study quantified the propagation characteristics (propagation time and probability) of dry and warm snow drought on warm season vegetation browning, using the proposed three-dimensional conditional probability framework, and evaluated the potential driving mechanisms using random forest. Findings indicated that while the propagation time and probability were long in late summer and early autumn, they were short in late spring and early summer. The probability of vegetation productivity loss in the warm season was positively impacted by the severity of dry snow drought, whereas it was negatively impacted by warm snow drought. The warm snow drought had a more noticeable effect on warm-season vegetation than had dry-type in changing environment, with soil moisture and wind speed playing a major role.