In June 2006 the NERC-funded Network for Calibration and Validation of EO data (NCAVEO) organised a cal-val field experiment in Chilbolton, north Hampshire involving 48 scientists from 20 organisations (click for list). The aim was to undertake a validation exercise based on the protocols and methods developed by the Validation of Land European Remote Sensing Instruments (VALERI) project, but modified as necessary for UK conditions. The experiment is a scoping exercise for the establishment of one or more VALERI sites in the UK as well as an opportunity to learn and share best practice amongst NCAVEO partners and the wider community.

The initial plan was to base the experiment at the Barton Bendish test site in East Anglia, but the absence of on-site instrumentation coupled with uncertainty about access to this site and its distance from the main research groups led to a search for other suitable sites. The one chosen was centred on the Services and Technology Facilities Council Chilbolton Facility for Atmospheric and Radio Research (CFARR), approximately 45 km north of Southampton (Figure 1). CFARR comprises a number of state-of-the-art instruments for measuring atmospheric properties, including the 25 metre diameter Chilbolton dish, a 3 GHz doppler-polarisation radar, 1275 MHz clear air radar and a UV vertical sounding LiDAR In addition, the site has a full suite of continuously operating meteorological instruments.

Datasets collected include Digi HRG data, remotely sensed data from 2 aircrafts, ground spectral data , atmospheric data, biophysical data, and fluvial geomorphological data.