Understanding the effects of rainfall variability on dryland vegetation

Background/Question/Methods

Rainfall variability is expected to increase with climate warming. We used the MODIS remotely-sensed estimations of tree cover (%) at 1 km2 to explore the patterns of tropical tree cover distribution in relation to rainfall variability.

Results/Conclusions

We found that rainfall variability is associated with reduced tree cover in the wet tropics globally. In contrast, high year-to-year variability is positive (South America), neutral (Africa) or negatively (Australia) related to tree cover in the dry tropics. We reflect on long-term observations to identify potential mechanisms that may explain these contrasting responses of tree cover to extreme rainfall events in drylands.