Physio-climatic controls on vulnerability of watersheds to climate and land use change across the United States

Understanding a watersheds vulnerability to environmental (climatic and land use)\ud change is crucial for managing such complex systems and is essential for water re-\ud sources management. However, obtaining projections of stream ow under changing\ud conditions across a variety of watersheds is challenging as every step of hydrologi-\ud cal modeling imparts uncertainty. These ubiquitous uncertainties in projections of\ud stream ow make it very challenging to provide useful information to water policy\ud makers and decision makers. In this study, we attempt to identify dominant controls\ud on watersheds vulnerability to climate and land use change independent of future\ud projections of climate change. We propose a de nition of vulnerability that can be\ud used by a diverse range of water system managers and is useful in the presence of\ud large uncertainties in drivers of environmental change like extreme ow conditions,\ud as well as others that are relevant from the point of view of instream organisms