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Space and Earth Remote Sensing: GIS Application to Environmental Impact Studies
3.2 The effects of multiple look direction radar and
backscatter enhancement from flooded terrain using
airborne SAR imagery
Synthetic Aperture Radar (SAR) has many advantages over conventional
optical/mechanical remote sensing systems. Some of these advantages are well
known i.e. nearly all types of weather, day or night operating capabilities with
synoptic scale imagery at relatively high resolution. The understanding of SAR
characteristics is important for optimizing its use. In this case the effects of
multiple look direction and the enhancement of the radar backscattered signal,
from flooded terrain, were of special interest.
False color composite radar images from three look directions were generated and
evaluated, using X-band Intera multiple look direction radar data of South
Louisiana, collected under the auspices of the U.S. Geological Radar Mapping
Program.
The enhancement of a radar signal from a flooded surface masked by a vegetation
canopy provides valuable information for both Earth and biological scientists.
This signal enhancement was corroborated by field data for an X-band radar of
flooded rice fields.
3.3 Moisture content analysis using Landsat 5 Thematic
Mapper data and generation of a water-table contour
map.
This study regards the extraction of moisture content data using conventional
Landsat 5, Thematic Mapper images. First, a statistical data analysis was conducted
with the aim of evaluating the data distribution in the seven different band images;
secondly, a clustering procedure was developed in order to compare the retrieved
classes with a moisture content ground survey. The spectral signatures extracted
from the training samples, chosen according to their supposed humidity condition,
were then processed band by band evaluating the information content for every
image. All information redundancy was thus avoided, and an infrared optimum
band was selected as being typical of the analyzed phenomena.
A water table contour map was generated from the radiometry of the pixel that
makes up the image, and then verified by measuring the piezometric surface depth
in different sample areas using ground surveys.
KEYWORDS
Environmental impact study, GIS, Thematic maps, remote sensing, risk analysis in
flooded terrain, moisture content in soil, ground water.
Space and Earth Remote Sensing: GIS Application to Environmental Impact Studies
3.2 The effects of multiple look direction radar and
backscatter enhancement from flooded terrain using
airborne SAR imagery
Synthetic Aperture Radar (SAR) has many advantages over conventional
optical/mechanical remote sensing systems. Some of these advantages are well
known i.e. nearly all types of weather, day or night operating capabilities with
synoptic scale imagery at relatively high resolution. The understanding of SAR
characteristics is important for optimizing its use. In this case the effects of
multiple look direction and the enhancement of the radar backscattered signal,
from flooded terrain, were of special interest.
False color composite radar images from three look directions were generated and
evaluated, using X-band Intera multiple look direction radar data of South
Louisiana, collected under the auspices of the U.S. Geological Radar Mapping
Program.
The enhancement of a radar signal from a flooded surface masked by a vegetation
canopy provides valuable information for both Earth and biological scientists.
This signal enhancement was corroborated by field data for an X-band radar of
flooded rice fields.
3.3 Moisture content analysis using Landsat 5 Thematic
Mapper data and generation of a water-table contour
map.
This study regards the extraction of moisture content data using conventional
Landsat 5, Thematic Mapper images. First, a statistical data analysis was conducted
with the aim of evaluating the data distribution in the seven different band images;
secondly, a clustering procedure was developed in order to compare the retrieved
classes with a moisture content ground survey. The spectral signatures extracted
from the training samples, chosen according to their supposed humidity condition,
were then processed band by band evaluating the information content for every
image. All information redundancy was thus avoided, and an infrared optimum
band was selected as being typical of the analyzed phenomena.
A water table contour map was generated from the radiometry of the pixel that
makes up the image, and then verified by measuring the piezometric surface depth
in different sample areas using ground surveys.
KEYWORDS
Environmental impact study, GIS, Thematic maps, remote sensing, risk analysis in
flooded terrain, moisture content in soil, ground water.