Graph of the Day: Ocean Surface Salinity Changes, 1950-2000
Patterns of 50-year surface salinity changes (PSS-78 50 / year). (A) The 1950–2000 observational result from P. J. Durack, S. E. Wijffels, “Fifty-year trends in global ocean salinities and their relationship to broad-scale warming”, J. Clim. 23, 4342 (2010). ABSTRACT: Fundamental thermodynamics and climate models suggest that 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. We show that ocean salinity patterns express an identifiable fingerprint of an intensifying water cycle. Our 50-year observed global surface salinity changes, combined with changes from global climate models, present 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 2° to 3° warmer world.
Ocean Salinities Reveal Strong Global Water Cycle Intensification During 1950 to 2000