Widespread spring phenology effects on drought recovery of Northern Hemisphere ecosystems

The authors reveal complex drought recovery responses to phenology shifts, in that early spring can shorten or lengthen recovery, while delayed spring following drought events delays it. These effects suggest a need to incorporate phenology aspects into resilience models. The time required for an ecosystem to recover from severe drought is a key component of ecological resilience. The phenology effects on drought recovery are, however, poorly understood. These effects centre on how phenology variations impact biophysical feedbacks, vegetation growth and, ultimately, recovery itself. Using multiple remotely sensed datasets, we found that more than half of ecosystems in mid- and high-latitudinal Northern Hemisphere failed to recover from extreme droughts within a single growing season. Earlier spring phenology in the drought year slowed drought recovery when extreme droughts occurred in mid-growing season. Delayed spring phenology in the subsequent year slowed drought recovery for all vegetation types (with importance of spring phenology ranging from 46% to 58%). The phenology effects on drought recovery were comparable to or larger than other well-known postdrought climatic factors. These results strongly suggest that the interactions between vegetation phenology and drought must be incorporated into Earth system models to accurately quantify ecosystem resilience.

Automated summary

The authors found that early spring phenology slows drought recovery, while delayed spring phenology prolongs it. More than half of ecosystems in the mid- and high-latitudinal Northern Hemisphere fail to recover from extreme droughts within a single growing season. The phenology effects on drought recovery are comparable to or larger than other well-known postdrought climatic factors, suggesting the need to incorporate these interactions into Earth system models.