Earth systems are dominated by water, from the broad controls on global climate by the oceans to the atomic scale water-rock interactions driving chemical weathering and therefore rock cycling. Department faculty examine these hydrological processes across a wide range of time scales, both re-constructing the paleo-processes from imprints left in soils and lake sediments and deploying extensive modern sensing networks in cities and across across urban and natural landscapes. Moreover, research focusing on hydrologic processes often is generated by interest in the tight coupling between water availability and the evolution of biogeochemical and geochemical processes. The inherently cross-disciplinary examination of the water cycle continue to generate fruitful and interesting research at the local, regional, and global scale.