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 Abileahabileah@jOmegak.com

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