Campaign prepares future land-surface monitoring

23 July 2007, 5:59pm

An ESA field campaign is underway to support development of the GMES Sentinel-2 mission and the candidate Earth Explorer FLEX mission to pave the way for future monitoring of the Earth's surface.

One of the important aspects of developing an Earth-observation (EO) mission is to ensure that the data meets users' exacting requirements. Thus, great effort is put into field activities to evaluate the future performance of an instrument. This campaign, called CEFLES2 (CarboEurope, FLEx and Sentinel-2), combines field experiments for two EO missions - Sentinel-2, being developed by ESA as part of the space segment for the GMES (Global Monitoring for Environment and Security) programme, and the candidate Earth Explorer FLEX mission.

Sentinel-2 is a multi-spectral imaging mission for high-resolution observation of land surfaces. It is expected to provide enhanced continuity of the French SPOT (Satellite Pour l’Observation de la Terre) missions and the US Landsat missions. Witin GMES, Sentinel-2 will provide information for land monitoring and emergency services.
The FLEX mission’s main aim is to make novel global observations of photosynthesis through the measurement of chlorophyll-fluorescence. This should lead to better knowledge of the role vegetation plays in the Earth's carbon and water cycles and ultimately contribute to an improved understanding of climate.

To support these two missions, the CEFLES2 campaign is exploiting the synergies between a large collection of measurements of different types of vegetation taken from the air and on the ground. The campaign is being carried out in coordination with CERES (CarboEurope Regional Experiment Strategy), including participants from Germany, Italy, France, Spain and the Netherlands.

The main campaign site is located within the CERES experimental area in Gascony in south-west France, with additional airborne acquisitions taken over Madrid and the Mediterranean coast. The first measurements were taken in April and June 2007 and another set will be taken in September, so that different stages of crop growth are represented. The aim is to obtain reference datasets to address the specific needs of the development activities for Sentinel-2 and the FLEX candidate mission.

The objective of Sentinel-2 is to collect quality and coordinated airborne optical and in-situ measurements. Luis Alonso from the University of Valencia, Spain, coordinator of the ground team during the June campaign, said: "Hundreds of kilometres of airborne imagery over many types of landscapes have been acquired along with a complete set of ground measurements taken by a consortium of European laboratories. This campaign's unique dataset will be a major contribution for defining algorithms for Sentinel-2 and for testing the new data processing techniques that are needed for this satellite."

Uwe Rascher from the Jülich Research Centre, who is responsible for coordinating the ground measurements for FLEX, explained: "With this campaign we are taking the first steps to develop a measuring tool to monitor vegetation florescence that will allow us to observe the capacity of photosynthesis of plant ecosystems in real time, and to better manage plant ecosystems under future climate scenarios."

The campaign has been very successful to date and scientists are anticipating the third part of the campaign in September, after which the results can be fully analysed to further development of the Sentinel-2 mission and the assessment studies for the candidate FLEX mission.

Source: European Space Agency, 23 July 2007, with permission

www.esa.int/esaEO/SEMFUKB474F_environmen…

European Space Agency