The freshwater cycle over land is fundamental for sustainability and resilience, yet is extensively modified and shaped by a vast range of human interventions in the land, water, and climate systems. The consequences of human water-cycle modifications can be non-linear, delayed, and distributed across boundaries, sectors, and scale. This complexity renders freshwater challenges difficult to govern and manage. We here propose a framework for understanding water's many functions for supporting, regulating, and stabilizing hydro-climatic, hydro-ecological, and hydro-social systems. This framework recognizes human impacts on major partitioning points, interactions among water functions, and stabilization and destabilization processes. A functional understanding of the freshwater cycle can integrate with social-ecological resilience-building principles, complement existing water sustainability governance approaches, and highlight the potential need for Earth-system-level governance of water. Recognizing water's diverse functional roles for resilience may promote a new generation of holistic and integrative water-land-climate governance. The freshwater cycle supports, regulates, and stabilizes the terrestrial biosphere and all social-ecological systems on Earth. However, a vast range of human activities across the land-water-climate continuum now modifies freshwater and gives rise to complex dynamics that renders freshwater challenging to govern in the Anthropocene. We here propose a conceptual framework for understanding key aspects of water's fundamental functions that underlie social-ecological resilience. A functional understanding of water may help promote sustainable and resilient governance of water.
One Earth, Volume 4, 19 February 2021,