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

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II - VALIDATION OF RS PRODUCTS FOR FIRE MANAGEMENT
a b R 2 Bias RMSE RMSES RMSEU MAD MADP
GEMI 0.12±0.18 -0.04±0.05 0.66 -0.004 0.06 0.010 0.06 0.04 14%
EVI (MOD 09) 0.88±0.19 0.04±0.06 0.51 -0.0019 0.07 0.010 0.07 0.05 16%
SAVI 1.5±0.2 -0.13±0.07 0.74 0.002 0.06 0.04 0.003 0.05 17%
EVI (MOD 13) 0.93±0.17 0.01±0.05 0.61 -0.008 0.06 0.012 0.06 0.05 16%
Table 1 - Statistics of the validation for the three indices.
5 - Conclusions
In this work we present a comparative study of spectral vegetation indices
with the aim of obtaining a simple empirical model for the estimation of
fire risk in the Galicia region. Eight different indices have been selected.
The variations suffered by each one, in a two weeks period, are used as the
entry parameter for the model. Three of the indices are shown to fit a linear
regression with the fire probability: EVI, GEMI and SAVI. From the validation
results we may conclude that the most appropriate indices for the
fire risk estimation are GEMI and EVI, with a relative error of about 15%.
In future works we will apply this model to other regions and include the
surface temperature as an additional input of the model.
Acknowledgements
This work has been financed by the Science and Innovation Spanish
Ministry (Projects CGL2007-64666/CLI, CGL2008-03668/CLI, and Juan de la
Cierva research contract of J.M. Sánchez).
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