After a fire, a strong reflectance decrease at optical wavelengths can be observed on satellite images, burnt areas having a lower reflectance in the near infrared channel than healthy vegetation.
The L3JRC consortium (Joint Research
Center, University of Leicester, Universidade Tecnica di Lisboa,
Université Catholique de Louvain) have derived burnt area maps
from the VEGETATION sensor by applying globally a regional algorithm
developed in the framework of the GBA2000 project. The algorithm that
has been applied is the modified IFI (International Forest Institute,
Russia) that calculates a temporal index based on near infrared
reflectance measurements and identifies rapid decreases in reflectance
over a spatial window of 200 km x 200 km (Tansey, 2002 ; Tansey et al.,
2004).
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Burnt scars detected from VEGETATION data over Siberia, July 14th 2000.
A pre-operational production line has been designed to monitor fires seasonality in near real time (every 10 days). This production chain was designed and developed in the framework of the geoland project. Every dekad, a synthesis of the occurrence of detection of a burn scars during the dekad is generated per grid cells of 0.5° x 0.5°. For each grid cell the time series of the detection is analysed and the most recent start of season (example below), peak and end of season are assessed. The resulting images of dates are updated every dekad. The seasonality products are generated for the period from 21st June, 2002 to 21st June 2004 over Africa.
The products Burnt areas + Seasonality are available, with a technical documentation (readme), at VITO through the geoland/CSP website
Tansey, K., Implementation of regional burnt area algorithms for the GBA2000 initiative. Publication of the European Commission EUR 20532, pp. 170, 2002.
Tansey, K et al., Vegetation burning in the year 2000 : Global burned area estimates from SPOT VEGETATION data, Journal of Geophysical Research-Atmospheres, Vol. 109, D14S03, 2004.