Sahara's edge studied from ground, air and space to improve water management   Tunisian and European scientists participating in AquiferEx, photographed after assembly of one of the four radar corner reflectors. Corner reflectors are used as ground control points and two of them for checking radiometry calibration in L-band.   This satellite image of the northern part of the Ben Gardane study area was acquired by the hyperspectral CHRIS image on ESA's Proba microsatellite during the AquiferEx campaign in Tunisia. It includes 'red edge' combinations of spectral bands sensitive to chlorophyll in healthy vegetation.   Spectroradiometric measurements over a homogeneous area for AVIS hyperspectral data calibration, carried out during AquiferEx.   DLR's Dornier Do-228 used to carry airborne sensors during the AquiferEx campaign   Part of a hyperspectral image strip of the Ben Gardane region acquired by the AVIS sensor during the AquiferEx campaign   Multi-polarised radar imagery of the same part of Ben Gardane region acquired by the airborne E-SAR sensor during the AquiferEx campaign   Alfalfa crop soil sampling for soil moisture determination, part of the AquiferEx campaign in Tunisia. AquiferEx results going to work for Aquifer, and future satellites     Kinematic phase differential GPS continuous measurements are carried out during airborne overflights for maximum geographic positioning accuracy. Aquifer and TIGER     A combined ITC and Delft University of Technology ground team performing radar ground penetration measurements during the AquiferEx campaign Release date: 27 May 2009