How Landsat Helps Texas

Texas relies on the Landsat satellites, operated with the U.S. Geological Survey (USGS), for decisions about its coast, cities and water. A USGS fact sheet describes three uses.

Mapping a changing coastline

The Texas coast draws residents, tourists and trade, but it is often hit by hurricanes and faces rising seas. Landsat data can document disaster damage by mapping disturbance right after an event, and improve models of both likely impact and recovery. Landsat also shows long-term trends: one study mined the Landsat archive from 1986 to 2015 and found that nearly 53% of the Texas coastline had retreated.

After Hurricane Harvey made landfall as a Category 4 storm on August 25, 2017, flooding covered the Gulf Coast; even through scattered clouds, its extent south of Houston is clear in these Landsat images. USGS.

Tracking urban heat

Texas cities bear the worst of its summer heat. Concrete and asphalt trap heat, raising city temperatures by several degrees and keeping them high through the night — the urban heat island effect. Measuring it block by block without satellites would take hundreds of weather stations; Landsat's thermal imaging makes it far more efficient. Researchers at Texas Christian University used Landsat to study heat in Dallas as early as 1995, and a 2020 study examined temperatures across local climate zones in Austin, San Antonio and Dallas–Fort Worth. Such work supports city efforts to save energy and protect health.

Measuring water use

One in seven working Texans is employed in agriculture, which uses more than half of the state's water. Landsat can estimate the hardest part of the water budget to measure: evapotranspiration, the water lost by evaporation from surfaces and transpiration from plants — a measure of how efficiently water is used that can guide decisions and allocations for irrigated cropland. A 2019 study of the Upper Rio Grande Basin, including parts of west Texas, used Landsat's long record to measure evapotranspiration from 1986 through 2015 and reveal long-term patterns of crop water use.

Landsat for the whole country

The USGS National Land Imaging Program supplies satellite imagery and other remotely sensed data to government, business, universities and the public, with worldwide access to Landsat through the USGS Earth Resources Observation and Science (EROS) Center. According to the fact sheet:

• Landsat is the most widely used land remote sensing source among federal civilian agencies.
• A 2017 USGS study put Landsat's annual economic benefit to the United States at $2.06 billion, far more than its costs.
• Landsat 8 and 9 together give 8-day repeat coverage; NASA and the USGS were reviewing a joint study to shape Landsat Next.
• The 50-year record — the world's longest of Earth's land surface — and a no-cost data policy let users study large areas and long-term change.

Sources

• U.S. Geological Survey: "Texas and Landsat," Fact Sheet 2021–3017.
• Studies cited by the fact sheet: Xu (2018), on Texas coastline change; Aniello and others (1995), on urban heat islands in Dallas; Zhao and others (2020), on urban heat in Texas; Senay and others (2019), on crop water use in the Upper Rio Grande Basin; Straub, Koontz and Loomis (2019), on Landsat's economic value.
• The fact sheet dates the coastline study to 2017 in its text but cites it as published in 2018; this page gives neither year.