Soil moisture refers to the water content in the top one centimetre of soil. Soil moisture is an essential land surface variable that has a significant impact on many environmental processes, such as the exchange of water and heat between the land surface and the atmosphere, the formation of precipitation and runoff, and the growth of vegetation canopies. Moreover, soil moisture plays a crucial role in the climate system and has a direct impact on the predictability of the atmosphere on sub-seasonal to seasonal time scales. Accurate measurements and modelling of soil moisture are essential for weather and climate forecasting, particularly in regions like Europe, where precipitation patterns can be highly variable and unpredictable.

According to a 2021 ESOTC Copernicus Report on European soil moisture in 2021, soil moisture was “near average compared to the 1991-2020 reference period”, having improved substantially from large negative deviations in 2018, 2019, and 2020. In 2020, it “was the third lowest since 1979” As the 2020 ESOTC points out:

Since 1979, Europe has seen a downward trend in soil moisture.