Network for Calibration and Validation of EO data (NCAVEO)
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This dataset contains 25m resolution raster formatted data derived from the Centre of Ecology and Hydrology's (CEH) Land Cover Map 2000 (LCM2000) data for the Thorney Island, South Coast of England, UK, NCAVEO calibration/validation (cal/val) test site. The NERC funded Network for Calibration and Validation of EO (NCAVEO) campaign was designed to illustrate and explain the processes involved in cal/val of earth observation data.
Sunphotometer data was collected on 17th June 2006 using three identical Microtops II instruments, as part of the Network for Calibration and Validation of Earth Observation data (NCAVEO) 2006 field experiment. The instruments were operated at three locations near Chilbolton: the roof of Chilbolton Facility for Atmospheric and Radio Research's (CFARR) main building, the Hampshire Golf Club and Cowdown Farm. On using the three instruments together on the roof of the CFARR main building, results showed differences between the three instruments, with data from s/n 8407 being closest to that measured by the Cimel sunphotometer at the same location. Note that the date of s/n 8407 was set incorrectly to 2005, but has been corrected in the NASA Ames formatted file. This should not affect the data collected. The same instrument also did not record the water vapour amount, so this is shown as -999.0 in the data file. On the ‘golden day’, 17th June 2006, measurements were made with all three instruments every five minutes between 09:30 and 11:30 GMT. Sporadic measurements were also made at earlier and later times. The s/n 8407 did not make a reading at 11.15 as anticipated. A large number of parameters and calibration constants were used to achieve these readings and are included alongside the main data. For further information please refer to the Microtops II User’s Guide.
As part of the Centre for Ecology and Hydrology Land Cover 2007 Pilot Project, a reconnaissance survey was undertaken on 12th May 2006 in a 60 x 60 km area (bounded by Ordnance Survey National Grid Reference X = 400000 to 460000, Y = 095000 to 155000) which included the Network for Calibration and Validation in Earth Observation (NCAVEO) test site. A recording tablet device was used for acquiring ground data for sample points in the defined area. The dataset consists of an ESRI shape file of point data, containing all the points recorded on a tablet device. Each point has a British National Grid X and Y co-ordinate and a class code. The dataset has not been checked or edited yet and a few of the records will be erroneous. The most obvious errors will be two or more points with identical locations but different codes, the final code will be the correct one. Some of the points for Salisbury Plain lie just outside the test area boundaries. A key to abbreviations used for field recording is also included and a list of thematic land cover classes and their codes to aid field reconnaissance, as used for Land Cover Map 2000.
This dataset includes reflectance spectra of Winter oats collected from Fairpiece field, near Chilbolton, as part of the Network for Calibration and Validation of EO data (NCAVEO) 2006 Field Campaign. The data was collected on the 18th June, using an ASD N4406 instrument. For information on the data's processing please see the metadata PDF in linked documentation. Please note that all raw spectra files collected during the NCAVEO campaign (labelled ***R_ASD0606**.***) have incorrect dates, indicating them to have been collected in July rather than June. The day of month and time (UTC) are correct in all cases. All other files (FSF spreadsheets and Excel/ENVI summary outputs) are also marked with the correct 15-18th June 2006 dates.
This dataset compromises eight flight lines which were acquired on 17th June 2006 using an Itres Instruments Compact Airborne Spectrographic Imager (CASI-3) as part of the Network for Calibration and Validation of Earth Observation data (NCAVEO) 2006 Field Campaign. The instrument was onboard a Cessna 404 aircraft operated by the UK Environment Agency (EA) and was operated in hyperspectral mode, with 32 spectral bands and a nominal ground resolution of 1m. The Environment Agency identified a possible spectral shift problem in the CASI-3 instrument during June 2006. The problem was corrected but it is still unknown how much the spectral shift occurred during data collection for NCAVEO. The document ‘CASI3 Wavelength correction for NCAVEO.pdf’ in further documentation provides further details. EasGeo software is also stored in the EasGeo folder in the directory as easgeo.sav, as well as documentation with further details on the data.
The Network for Calibration and Validation of EO data (NCAVEO) ground data collection programme included a series of transects on the River Test at Chilbolton Cow Common, an area of semi-natural wet grassland. The river survey was carried out on the 16th June between 11:15 and 13:15 at site Chilbolton 1 and 15:30-17:00 at Chilbolton 2, the day before the ‘golden day’ on which the airborne data were collected by the Environment Agency / Natural Environment Research Council (NERC). The sampling strategy used was based on the desire to capture; (1) data over the range of water depths, (2) a dense and extensive sample of data to allow for bathymetric modelling of the river regions and (3) data over a broad range of substrate types to represent all varieties within the study region (e.g. from marginal vegetation to silts and to gravels). The variables recorded included: Easting; Northing; Water depth (cm); Depth to bed (cm); Surface velocity (m/s); Dominant substrate. Surface velocity was measured using a Valeport uni-directional electro-magnetic current meter (Valeport Ltd.). For more information on the collection and processing of the data please see the dataset's metadata document, in linked documentation. A video of David Spear describing the survey is available also included in the directory.
As part of the 2006 Field Campaign of the Network for Calibration and Validation of EO data (NCAVEO), an Intergraph Z/I Imaging Digital Mapping Camera (DMC) was used to collect data in 4 spectral bands in the visible and near infrared, at a nominal ground resolution of 65cm. The Chilbolton site was flown over on the 9th June 2006 by the Ordnance Survey, resulting in 84 strips captured over the Area of Interest (2048 x 3072) with 60% overlap along the track. The data was orthorectified to the British National Grid using photogrammetric methods.
This dataset contains Aerosol Optical Thickness (AOT) data, collected at Chilbolton Facility for Atmospheric and Radio Research as part of the Network for Calibration and Validation of EO data (NCAVEO) 2006 Field Campaign. Measurements were taken every 15 minutes using a Cimel CE318-2™ sun photometer, which is part of AERONET. For more information on the dataset please see the dataset's metadata file in linked documentation.
This dataset contains 25m resolution raster formatted data derived from the Centre of Ecology and Hydrology's (CEH) Land Cover Map 2000 (LCM2000) data for the Monks Wood, Cambridgeshire, UK, NCAVEO calibration/validation (cal/val) test site. The NERC funded Network for Calibration and Validation of EO (NCAVEO) campaign was designed to illustrate and explain the processes involved in cal/val of earth observation data.
This dataset consists of an animation of the sky conditions at Cowdown Farm, near Chilbolton, compiled from 40 photos taken over the ‘golden day’, 17th June 2006, as part of the Network for Calibration and Validation in Earth Observation 2006 experiment. A NIKON E995 camera was used with a resolution of 2048 x 1536.