geotools 2009 conference a process for mapping shorelines and intertidal zones with multitemporal...
TRANSCRIPT
GeoTools 2009 Conference
A Process For Mapping Shorelines and Intertidal Zones With Multitemporal LANDSAT 7 Images
Process input: a series of LANDSAT images; E.g., 20 images over a 2 year span
Process output: Water cover map and shorelines with 15 m resolution. Water cover time is color coded as 5% (dark red) to 100% (dark blue).
Processing Algorithm
DenoiseRadiometric
scaling (Pan band)
Subpixelregistration
Multitemporal set ofLANDSAT bands 4 ,5, & 8
Referenceimage
Coarse resolutionwater cover
based onNIR & SWIR
Coarse shorelines
Refinedradiometricscaling for Pan band
Max/min water coverbased on
MWIR
Pan sharpenedshorelines
Water covermap and
shorelines
Benefits of LANDSAT 7 relative to other satellites
• LANDSAT has the most revisits in archive. Worldwide 16-day revisits since 1999*. This is essential to any sort of multitemporal analysis.
• LANDSAT’s eight spectral bands includes the three most suitable for mapping water bodies - SW, MW, and Thermal IR bands
• And since late 2008 the entire inventory of LANDSAT imagery has been made available free with electronic downloads. This makes multitemporal analysis affordable.
* In archived data the revisit time is variable, average ~1/month; LANDSAT 5 images also available, going back to 1984.
Comparison of various satellites
LANDSAT SPOT 4 QuickBird 2
Number of archived images 1999-2008
212 2 1
IR bands for mapping water area
NIR, SWIR, MWIR, and TIR
NIR & SWIR NIR
Resolution (with pan-sharpening)
15 m 10 m 0.5 m
Imagery cost per km2
$0 >$1 >$20
Total cost for 20 images
$0 >$8,000 >$160,000
For a hypothetical project requiring 20 Pan+MSI images over 10-year span, 400 km2 area centered on El Golfo De Santa Clara (31.98N,114.95W)
Mouth of the Colorado River at the North end of Gulf of California.
Part time aquatic farm activity
Bathymetry in the intertidal zone
Process runs on a dedicated server
Access to the server is free. Instructions for logging on can be found at jOmegak.com/jCube/.
Contact: Ron [email protected]
User logs on the server jk server
Images are downloaded directly from USGS portal to the jk server
USGS LANDSAT portal
Remote user
2 km wide intertidal zone, tidal rivers
Part of the shoreline in North Gulf of California
semi-dry lake
Vicinity of the San Mateo Bridge (San Francisco Bay)
Protected wetlands covered with water approximately 30% of the time.
4 images from 2000 and 4 from 2008 were combined to show the 8-year change (green) in the Dead Sea shoreline