 The study found that early summer drought conditions in the Rocky Mountains have a significant impact on ecosystem productivity, with four-summer drought sensitivity being spatially heterogeneous and primarily dependent on plant type and elevation. Results also showed that years with earlier snow melt and drier four-summer conditions lead to lower peak NDVI, and additional key controls related to surface energy exchanges, hydrological processes, and underlying geology were identified using random forest analysis. The study suggests that this remote sensing-based approach can be used to identify vulnerable or resilient regions to climate perturbations and inform future research. This article was authored by Haruko M. Wainwright, Christoph Stiefel, Sarah D. Truttner, and others.