Global assessment of the sensitivity of water storage to hydroclimatic variations

Observing basin water storage response due to hydroclimatic fluxes and human water use provides valuable insight into how a basin stores and discharges water.  Quantifying basin storage change attributed to climate and use is critical for water management yet remains a challenge globally.  Observations from the Gravity Recovery and Climate Experiment (GRACE) mission are combined with hydroclimate fluxes of precipitation and evapotranspiration to document the sensitivity of available water storage for global basins.  Our results detect substantial global water storage sensitivity to changes in hydroclimatic fluxes.  Comparison with Budyko-derived metrics substantiate our findings, demonstrating that basin water storage resilience to short-term water deficits is linked to basin partitioning predictability, and uniform seasonality of hydroclimatic fluxes.  Our study demonstrates how small shifts in hydroclimate flux may affect available water storage potentially impacting billions globally.