Leaf Area Index (LAI) measurements were made in three fields near Chilbolton, as part of the Network for Calibration and Validation of Earth Observation data (NCAVEO) 2006 Field Campaign. Measurements were carried out over 14-15 June 2006 in fields Brockley (spring barley), Big Croft (oil seed rape) and Rickyard (winter wheat), each of which were planted with different crop types. LAI measurements were made with the LAI2000 instrument loaned from INRA, France (Inst. Ref: N4431), including shadow cap (180 degrees) and measurement configuration: one top of canopy reading (reading A in files) followed by one bottom of canopy (reading B in files).

Within the main sensor the LAI2000 instrument has five separate silicon detectors arranged in concentric rings. When radiation is projected onto the detector each ring sees a different range of zenith angles, up to a maximum 74º field of view. There is no response at zenith angles between 74º and 90º. The sensor is filtered to respond only to radiation below 490nm to minimise the impact of leaf reflectance and transmittance on measured values. The outputs of the five detectors were measured simultaneously for each above or below canopy measurement. Five sample points were located within tramlines in each field and five 10 metre long transects were then set-up, centred on each of these points. 10 measurements were made at each flag. For further details regarding the data's collection and structure, please see the associated metadata document in linked documentation.