Science Source

Global land moisture trends: drier in dry and wetter in wet over land

States the “dry gets drier, wet gets wetter” (DGDWGW) paradigm is widely accepted in global moisture change
Examines global moisture trends using satellite soil moisture for the past 35 years (1979–2013)
Results indicate that approximately 30% of global land has experienced robust moisture trends (22.16% have become drier, and 7.14% have become wetter)
Finds that only 15.12% of the land areas have followed the DGDWGW paradigm, whereas 7.77% have experienced the opposite trend
Finds that there is a significant “drier in dry, wetter in wet” (DIDWIW) trend paradigm; 52.69% of the drying trend occurred in arid regions, and 48.34% of the wetter trend occurred in the humid regions
Overall, 51.63% of the trends followed the DIDWIW paradigm, and 26.93% followed the opposite trend
Identifies the DGDWGW and DIDWIW paradigms in low precipitation-induced arid regions in which the dry soil led to an increasing sensible heat flux and temperature and subsequently potential evapotranspiration