Ocean Salinities Reveal Strong Global Water Cycle Intensification During 1950-2000
Fundamental thermodynamics and climate models suggest dry regions will become drier and wet regions will become wetter in response to warming. Efforts to detect this long-term response in sparse surface observations of rainfall and evaporation remain ambiguous. This research shows ocean salinity patterns express an identifiable fingerprint of an intensifying water cycle. Observations from a fifty-year period (1950-2000) of global surface salinity changes, combined with changes from global climate models, offers robust evidence of an intensified global water cycle at a rate of 8 ± 5% per degree of surface warming. This rate is double the response projected by current-generation climate models and suggests that a substantial (16 to 24%) intensification of the global water cycle will occur in a future world that is 2° to 3° warmer.