The ESA said the maps derived from its Envisat satellite are expected to lead to better weather and extreme-event forecasting, such as floods and droughts.

"Predicting when and where floods are likely to happen is becoming more and more important," said Geoff Pegram of South Africa's University of KwaZulu-Natal. "Although we cannot prevent floods, we can anticipate them and hopefully get people out of the way. This brings hydrology into the 21st century and makes life better for people."

Despite its importance for agricultural planning and weather forecasting, there has been a lack of soil moisture information in Africa because of the high costs of in-situ measurement networks. In addition, unlike satellite observations, point-based measurements are often not sufficient to provide an overall picture over large areas that may be effectively used in models.

The ESA-backed project is said to be the first to demonstrate satellite-based synthetic aperture radar instruments can deliver soil moisture data of high spatial and temporal resolution.