Changes in soil moisture and land surface aridity are due to changes in the relative balance of precipitation and ET. Soil moisture is also affected by irrigation. Regional trends derived from satellite remote sensing products show increases and decreases in annual surface soil moisture of up to 20% or more between the late 1970s and late 2010s . For example, using the ESA CCI SM v03.2 COMBINED products , approximately 0.9 billion people live in regions with decreasing surface soil moisture, and 2.1 billion people live in regions with increasing surface soil moisture . However, there are disagreements between data sets on the direction of change in some regions , so quantification is subject to low confidence.
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report