7th Workshop on Forest Fire Management - EARSeL, European ...

Abstract: The aim of this paper is to show the results of a comparative
analysis of some of the most commonly used spectral indexes in burnt land
mapping applications. The objective is to verify its operative consistency
between ASTER and MODIS data derived indexes. The analyzed indexes were
the SVI, NDVI, TVI and SAVI for ASTER and BAIM and NBR for MODIS data.
This test has been focused on establishing the discrimination ability of
each index between the recently burned zones and other land covers using
a post-fire image from Gran Canaria (Canary Islands-Spain) 2007 fire. The
results have been compared with the burnt area perimeter provided by a
SPOT multitemporal image study.
1 - Introduction
BURNT AREA INDEX USING MODIS AND ASTER DATA
A. Alonso-Benito, P.A. Hernandez-Leal, A. Gonzalez-Calvo,
M. Arbelo, A. Barreto & L. Nunez-Casillas
Grupo de Observacion de la Tierra y la Atmosfera (GOTA), Avda. Astrofisico Francisco Sanchez s/n,
Facultad de Fisicas, Universidad de La Laguna, S/C Tenerife, Islas Canarias (España)
asaloben@gmail.com
Satellite data constitute a useful tool for a rapid assessment, usually at no
cost, of the area affected by a wildfire, and the pixel burnt severity estimation.
Many authors have written about the appropriateness of different
satellite sensors in the mapping of burned areas ie. AVHRR and MODIS
(Chuvieco et al., 2005) and ASTER (Nikolakopoulus, 2003). During the summer
of 2007, a large fire took place in Gran Canaria Island (Spain) affecting
nearly 15,000 ha. This region, in the south of the island, has been
taken as the test site.
2 - Data and methodology
With the aim of testing the proposed indexes for burnt pixels identification,
an ASTER Level 1B image (March 6, 2008) has been used. All ASTER evaluated
indexes use VNIR and SWIR bands of the sensor, which have been corrected
for reflectance values R TOA as described in (ERSDAC, 2007). On the
other hand, a Terra-MODIS Level 1B image from 15 May 2008 has been used
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