Water is at the core of the most difficult sustainability challenges facing humans in the modern era, involving feedbacks across multiple scales, sectors, and agents. We suggest that a transformative new discipline is necessary to address many and varied water-related challenges in the Anthropocene. Specifically, we propose socio-hydrology as a use-inspired scientific discipline to focus on understanding, interpretation, and scenario development of the flows and stocks in the humanmodified water cycle across time and space scales. A key aspect of socio-hydrology is explicit inclusion of two-way feedbacks between human and water systems, which differentiates socio-hydrology from other inter-disciplinary disciplines dealing with water. We illustrate the potential of socio-hydrology through three examples of water sustainability problems, defined as paradoxes, which can only be fully resolved within a new socio-hydrologic framework that encompasses such two-way coupling between human and water systems.
Need for a Water Focus on Sustainability ScienceWater represents a key aspect of sustainability challenges facing humans in the Anthropocene [Maass et al., 1962;Falkenmark and Rockström, 2004]. Human appropriation of water resources and modification of landscapes exert an accelerating influence on water-cycle dynamics from local-to global scales and decadal-to century timescales [Vörösmarty et al., 2000]. Human actions scale up in surprising and unpredictable ways to generate a suite of diverse water sustainability challenges that must be incorporated into new approaches to water science and management.Examples of wicked problems that continue to vex scientists and policy makers include: trade-offs among ecosystems, hydropower, and livelihoods in the transnational Mekong Basin [Ziv et al., 2012]; effects of human settlements in flood-prone areas on increased flood risk and fatalities in Africa [Di Baldassarre et al., 2010]; and expanding hypoxic zones in the Gulf of Mexico resulting from nutrient loading in the agricultural headwaters of the Mississippi River [Turner and Rabalais, 2003]. Due to the urgency of these problems, contemporary scholarship should draw from natural sciences, social sciences, and the humanities, to better understand the dynamics arising from the two-way coupling between water and humans in each case.There have been calls for a transformative new water discipline that integrates the multiple perspectives needed for confronting water challenges in the Anthropocene. For example, we should build upon the tradition in hydrology to study relatively pristine systems, in which human actions tend to be incorporated simply through parametric approximation [Wagener et al., 2010], with richer understanding of coupled human-water system dynamics [Fishman et al., 2011]. Likewise, humanistic approaches to the study of water-law, philosophy, history, and ethics-can be further integrated with scientific knowledge [Wescoat, 2013]. The most effective way to create such a new discipline is to frame it a...
