Water held in soil plays an important role in the climate system. The dataset released by ESA is the first remote-sensing soil moisture data record spanning the period 1978 to 2010 a predecessor of the data now being provided by ESA's SMOS mission.
The datasets are now available to the science community for feedback analyses and climate model validation.
The amount of water held in global soils makes up only about 0.001% of the total water found on Earth.
It is crucial for plant growth, but is also linked to our weather and climate. This is because soil moisture is a key variable controlling the exchange of water and energy between the land and the atmosphere: dry soil emits little or no moisture to the atmosphere.
A recently detected decline in the global evaporation trend could, for example, directly be explained by limited moisture supply.
The relationship between soil moisture and the climate system is not yet fully understood, and global long-term soil moisture observations have so far not been available. That means the evaluation of climate models with regard to the drying and wetting trends and associated feedbacks with temperature is still difficult in many regions worldwide.
In 2009, ESA launched a dedicated satellite mission, SMOS, that provides high quality and direct measurements of soil surface soil moisture. While the key applications for SMOS data are weather forecasting, hydrology and water management, the mission also provides data in near-real time for operational applications.
However, to address the current lack of historical long-term soil moisture data for climate applications, ESA has also been supporting the development of a global soil moisture data record derived by merging measurements acquired in the past by a series of previous and current European and US satellites.
These activities were initiated within the Water Cycle Multi-mission Observation Strategy
|Contact: Robert Meisner|
European Space Agency