The European Space Agency (ESA) has selected five candidate missions for initial feasibility studies in its programme to "enhance the capacity to predict the evolution of the Earth's environment" as part of the agency's Living Planet programme.

The programme, introduced in 1999, comprises Earth Explorer Core and Opportunity missions. The five core missions under study are: the Atmospheric Chemistry Explorer; EarthCARE, an Earth clouds aerosol and radiation explorer; SPECTRA, which is to study surface processes and ecosystem changes through response analysis; a water vapour lidar space experiment, WALES; and WATS, a study of water vapour and wind in the stratosphere and troposphere.

Two core missions are under development, to study gravity and steady state ocean circulation and atmospheric dynamics. The first firm Earth Explorer Opportunity Missions are: Cryosat, to measure the thickness variations in polar ice sheets and SMOS, to demonstrate the observation of soil moisture and ocean salinity.

Source: Flight International