The Once and Future Hydrology Is Whole Earth Hydrology

Abstract We here argue for a new paradigm to advance pursuit of truth in global freshwater science. Our proposed Whole Earth Hydrology is hydrology that is explicitly empirical and discovery‐based, grounded in primary data, detailed at scale, and incorporates humans as essential. We argue for Empiricism as a rational response to the limits of rationality as the basis for hydrologic science. We embrace fieldwork, machine learning, and parsimonious hydrologic modeling (provided parameters are, at most, circumspectly interpreted) so long as they are pointed at a common goal: fundamental freshwater understanding at scales meaningful to humans and ecosystems in a hydrosphere where human alteration is the norm, not the exception. The once and future hydrology is, we hope, one where we first measure, then reliably and robustly predict, and then begin to unravel truth.