Terrascope: LANDSAT Ortho Mosaics for the 1970s, 1990, and 2000

Terrascope is a Google Earth implementation of LANDSAT MSS, TM, and ETM+ ortho mosaics for the 1970s, circa 1990, and circa 2000. It provides imagery as superoverlays with resolutions of 57 metres/pixel for the 1970s, 28.5 metres/pixel for circa 1990, and 14.25 metres/pixel for circa 2000. The project is sourced from KCL and Mark Mulligan and is designed to allow rapid visual comparison of land cover change across these periods.

Use Cases

• Visual change detection for desertification based on multi-decade LANDSAT imagery.
• Monitoring urbanisation patterns based on historical ortho mosaics from the 1970s to 2000.
• Assessing coastal, fluvial, and water body changes based on time-series satellite imagery.
• Awareness raising for habitat loss hotspots based on visual comparison of land cover.
• Conservation prioritisation based on observed historical land use change.

Strengths

• Provides imagery at three distinct time periods: the 1970s, circa 1990, and circa 2000.
• Offers specific spatial resolutions: 57 metres/pixel for the 1970s, 28.5 metres/pixel for circa 1990, and 14.25 metres/pixel for circa 2000.
• Includes metadata layers for the 1990 dataset, such as image names and dates of capture.

Limitations

• Data quality and resolution are reduced for older imagery, and some parts of the globe are missing.
• Row count, file formats, and license information are unknown.
• Last update date is unknown; freshness unverified.

Provenance

Source

KCL, Mark Mulligan

Collection Method

Ortho mosaics processed from LANDSAT MSS, TM, and ETM+ satellite imagery.

Time Range

1970s, circa 1990, circa 2000

Geography

Most of the world, though coverage may be incomplete.