IAFE   05512
INSTITUTO DE ASTRONOMIA Y FISICA DEL ESPACIO
Unidad Ejecutora - UE
artículos
Título:
Model investigation about the potential of C band SAR in herbaceous wetlands flood monitoring
Autor/es:
FRANCISCO MATIAS GRINGS; PAOLO FERRAZZOLI; HAYDEE KARSZENBAUM; MERCEDES SALVIA; PATRICIA KANDUS; JULIO CESAR JACOBO-BERLLES; PABLO PERNA
Revista:
INTERNATIONAL JOURNAL OF REMOTE SENSING
Referencias:
Año: 2007
ISSN:
0143-1161
Resumen:
Wetlands are areas where the presence of water at
or near the soil surface drives the natural system. Imaging radars (SARs) have distinct characteristics
which make them of significant value for monitoring and mapping wetland
inundation dynamics. The presence or absence of water (which has
a much higher dielectric constant than dry or wet soil) in wetlands may
significantly alter the signal detected from these areas depending on the dominant
vegetation type, its density and height. The objective of this paper is to
present our current research efforts to explain and correctly simulate the
radar response of wetland vegetation/inundation mixtures, and use simulations
as an aid for retrieval applications.
The
radar response of junco marshes under different flood conditions and vegetation
stages is analyzed using a set of 13 multipolarization ENVISAT ASAR scenes
acquired over the Paraná River Delta marshes during the period 2003-2005. The
main aspect of the approach followed is the simulation of SAR wave interactions
with vegetation and water, using an adapted and improved version of the EM
model developed at Tor Vergata University. Obtained results indicate that with
the refined EM model, it is possible to represent with a good accuracy VV and
HH SAR responses of junco marshes for a variety of environmental conditions.
Further work and data are needed to explain measured HV backscattering. The
general agreement obtained between simulations and observations permitted the
development of a simple retrieval scheme, and estimates of water level below
the canopy were obtained for different environmental conditions. RMS errors of
forward simulations and retrievals are reported and discussed.