iown with a sufficient
annels instead of using
ipe is the same for each
tion because they don't
hannels 4 and 5 is: R45
inces measured by the
ng the snow reflectance
sition as at the time of
ween 0° and 315° and
measured mean convex
nd reflectance without
in an operationnal way.
s done for other ratios:
grain size and does not
tionnal reflectances and
IX)
- 0.6
1-0.4
700 800 900 1000
nicrometers)
e in the Alps. The main
;ensing data acquisition,
ime, 2 spacebome. This
study the usefulness of
satellite data to retrieve helpful information on the snow mantle (temperature, snow type) and to validate
snow metamorphism models, to intercalibrate different sensors. Preliminary results on temperature and snow
grain size from the 24 April 1992 experiment are very satisfactory. We will complete this work and do the
same kind of studies for the other experiments.
ACKNOWLEDGEMENTS
The ARAT aircraft were operated by the Institut Géographique National, the push-broom by A. Pasquet
from CNES and J. Duffaut from DERO, the ISM spectrometer by D. Alcayde, G. Marty from the Centre
Spatial d'Etude du Rayonnement and J.P. Bibring, B. Gondet from the Institut d'Astrophysique Spatiale.
Those experiments were funded by the French Programme National de Teledetection Spatiale and the
Centre National d'Etude Spatiale.
We are grateful to the numerous colleagues who participated to the field work.
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