Landsat 9 continues nearly 50 years of Earth observation

The fog around Vandenberg Space Force Base along the central California coast lifted just in time this morning to launch Landsat 9, a joint Earth observation mission between NASA and the United States Geological Survey (USGS) and United States Department of Agriculture (USDA). The satellite was lifted in to orbit aboard an Atlas V rocket at 11:12 a.m. local time.

Landsat is NASA's longest continuous program, dating back to the launch of Landsat 1 on July 23, 1972.   That longevity is has provided a continuous record of changes to Earth's land surface, making up about 30% of the Earth's surface.

These images provide a valuable record to researchers and managers who work across wide geographical areas and applications. The data helps make better decisions about agriculture, fire, natural disasters, urban growth, water management, and forest management, especially over time.

NASA and the USGS opened up its global archive of satellite imagery with the launch fo Landsat 3 in 1978. Countries, including those unable to launch their own satellites, were able to make use of the data to manage natural resources.

For comparison, if we had a scale Landsat 9's near-polar, sun-synchronous at an altitude of 438 miles would be about a little under 4 feet above the the Daily Planet.  Don't look for museum officials to add a Landsat model any time soon.  At the Daily Planet's scale, the satellite would be the size of a human red blood cell.

Mapping past floods helps predict future ones according to Dr. Christopher Soulard, a research geographer with the USGS's Western Geographic Science Center in California.

"Having a baseline of inundations to compare to more recent characteristics will allow PLACE (Patterns in the Landscape–Analyses of Cause and Effect) to identify the key land-cover changes that can be linked to altered flooding patterns." described Soulard.

Even as flood waters recede, impacts to water quality are long felt.

When Hurricane Florence dumped an estimated 8 trillion gallons of water on the state in 2018, the Trent River southwest of Kinston rose to more than double flood stage. Landsat images showed how runoff from the floods impacted White Oak River, New River, and Adams Creek.  soils, sediments, decaying leaves, pollution, and other debris is clearly visible as it flows into the Atlantic.

More recently, Landsat 8 spotted oil slicks off the southeastern Louisiana coast earlier this month. It is believed to be coming form submerged pipelines near Port Fourchon, a major hub of the oil and gas industry, damaged by Hurricane Ida.

The mission also captured images of flooding along Louisiana coast following Hurricane Ida.

Combined with other data from satellite radar missions, glaciologists have used Landsat images to identify and track cracks and ridges in along glaciers in Greenland, noting how they increase speed as they near the coast.

Scientists from the University of Colorado at Bolder used Landsat images in studying Antarctica’s northern George VI Ice Shelf. They found record melting during the 2019-2020 summer season compared to 31 previous summers .Scientists also studied more than 400,000 Landsat images collected between 1984 and 2018 and found river ice to be similarly declining.