Quality Monitoring & Mapping
Analysis Inc. has developed unique software to determine synoptic
water quality parameters using satellite
imagery. This software, known as Quantitative Shoreline Characterization
(QSC 2), is an adaptation of the IMAGINE
Subpixel Classifier and provides the following new functionality:
· Bathymetric Analysis
· Turbidity Analysis
· Quantitative Terrain Categorization
The Bathymetric and Turbidity Analysis capabilities use satellite
imagery, primarily Landsat Thematic Mapper, to perform water depth,
bottom material, and water quality mapping for a specified area
The Quantitative Terrain Categorization capability provides information
on the material composition of each land pixel within a specified
area of interest, i.e., it identifies the principal scene materials
and the fraction of each material in each pixel. This is much more
powerful than most traditional classifiers.
Photobathymetry using satellite and airborne multispectral sensors
is not new, but has only experienced limited success in the past.
Several factors can affect performance: not correcting for surface
reflections and sun glints, not correcting for bottom material type,
not accounting for water column characteristics, inadequate calibration
for environmental effects, and lack of compensation for mixed bottom
materials, depths, and water column characteristics within individual
QSC 2 software applies subpixel technology to address all these
problems. It includes a unique environmental correction process
and explicitly accounts for sun glints at the subpixel level. Mixed
depths, bottom materials and water characteristics are addressed
through the same technology used by the Subpixel Classifier.
The result is a more accurate estimate of bottom depth and more
information about bottom depth, bottom type, and water column characteristics
(turbidity, visibility, suspended chlorophyll, suspended sediments,
and dissolved organic carbon).
Most terrain categorization algorithms segment the scene into regions
and allow you to assign a land cover type to each region. But only
QSC can identify mixed land cover types and specify the fraction
of each type in a given pixel.
It does this by using the same subpixel technology found in AAI's
Subpixel Classifier. The result is a more accurate and more
useful terrain categorization.
Includes material © Space Imaging L.P.
The combination of bathymetry analysis and subpixel terrain categorization
results in a complete quantitative characterization of the littoral
area. AAI is currently offering water quality mapping as an information
service. The QSC 2 software is not available for sale.