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Increasingly severe drought and associated reductions in water availability to plants and ecosystems have emerged as predominant climate characteristics of the southwestern U.S. (SW) at the beginning of the 21st century.� This growing aridity and likely changes in precipitation seasonality and intensity represent substantial challenges to SW land managers tasked with sustaining or restoring these important ecosystems. These challenges are further complicated by significant landscape-level heterogeneity in soil-geomorphic properties that mediate vegetation responses to multi-temporal climate drivers. Understanding how broad-scale climate drivers will impact ecosystems at local scales is therefore of paramount importance for designing effective management strategies to mitigate and minimize undesired ecosystem changes.� The response of SW ecosystems to droughts of the 20th and 21st centuries provides clear examples of variability in climate-plant relationships that are mediated by soil-geomorphic unit vulnerability.� Here, we present results from two ongoing drought experiments near Moab, UT.�� In one study, we are imposing a chronic but subtle drought (35% precipitation reduction) using passive removal shelters, across a wide geographic region. Over seven years, we have been examining plant cover changes and mortality of four dominant plant functional types: C3 grasses, C4 grasses, C3 shrubs and C4 shrubs. �Results from this long-term experiment show varying resistance and resilience to chronic drying among dominant functional types, with cool season grasses showing lowest resistance and resilience.� Second, we report results from a more recent study in which we are imposing extreme seasonal drought (66% reductions in the summer or winter) in a grassland system and have found dramatic shifts in species abundance following only two years of seasonal droughts. Taken together, results from these experiments suggest that both chronic and seasonal changes in water availability can alter the structure and function of the Colorado Plateau ecosystem by differentially impacting key plant functional types.