Data continuity of Landsat-4 TM, Landsat-5 TM, Landsat-7 ETM+, and Advanced Land Imager (ALI) sensors

Abstract

The data from the Landsat program constitutes the longest record of the Earth's surface as seen from space. Landsat 1 was launched in 1972 with the Multi-Spectral Scanner sensor (MSS), which was specifically designed for land remote sensing. This sensor proved so valuable that it was used with four subsequent Landsat missions. In 1982, Landsat 4 was launched with two sensors, MSS and a new sensor called the Thematic Mapper (TM) which had significant improvements in resolution as well as additional bands. The same payload was launched on Landsat 5 in 1984. Landsat 6 was launched in 1993 but failed to reach orbit. Landsat 7 was launched in 1999 with an improved TM sensor called the Enhanced Thematic Mapper (ETM+). The Advanced Land Imager (ALI) was launched in 2000 on the EO-1 (Earth Observer-1) satellite to test technology that will be used for the next Landsat platform, Landsat 8. In comparison to Landsat 7 ETM+, EO1 ALI provides a greater signal to noise ratio, a pushbroom sensor, greater quantization, and additional wavelength bands. As technology evolved, newer Landsat sensors were modified slightly while keeping in mind the importance of historical data continuity. There is a keen interest in documenting data continuity over the different Landsat sensors. This study attempts to quantify (within the limits of available information) data continuity over the three most recent Landsat sensors and the EO-1 ALI sensor. The data set in this analysis includes images from Landsat 4, 5, and 7 TM beginning in 1989 and images from the EO-1ALI platform acquired in 2001. All the images used were received radiometrically corrected to NASA level 1.