Tracking urban change and flood risk with Landsat satellite

March 20, 2014, NASA's Goddard Space Flight Center
This is an artist's rendition of the Landsat 8 satellite. Credit: NASA/USGS

When it comes to helping communities across the United States stay up-to-date on their flood risk, the Landsat satellite can take a bow.

Landsat images help track urban change, a factor that can impact a community's flood risk. The Federal Emergency Management Agency, or FEMA, uses these images to help identify where they should launch a new flood study. Flood studies determine how prone different neighborhoods are to floods of a certain intensity or likelihood.

Successful flood studies require an arsenal of tools, however, including data on river flows and storm tides, hydrological and hydraulic analysis of landscape and river systems, and historic rain data, to name a few.

These studies have adding satellite data from Landsat to the toolkit. With its archive of images capturing sprawling cities and new developments, Landsat helps FEMA track how building and construction is impacting an area's landscape.

Earth-observing Landsat satellites have been capturing images of the planet's surface since 1972. Landsat 8, the newest satellite in the joint NASA and U.S. Geological Survey program, was launched Feb. 11, 2013, and now collects more than 400 images per day. New and archived Landsat data are available free to the public from USGS. Researchers put the free data to a multitude of uses.

One is called the National Urban Change Indicator, or NUCI, a product developed by MDA, a company that makes geo-spatial products derived from satellites. Using satellite imagery, NUCI detects if an area has undergone a human-induced change over a 25-year period.

"If you identify areas where urban change is accelerating, there are consequences," said Zack Roehr, a senior spatial analyst with Dewberry, Fairfax, Va., a FEMA subcontractor.

Urbanization can spell trouble for flood risk. Soil typically acts like a sponge, absorbing water from rainfall. When soil is covered with concrete or other impermeable material, water has nowhere to flow except towards storms and rivers, thereby increasing .

"The ground is no longer able to hold water, which means local flooding sources are going to receive more of that water," Roehr said. "The flooding characteristics are going to change."

Explore further: Landsat satellites track continued Missouri River flooding

Related Stories

Image: Landsat 8's first year

February 12, 2014

On Feb. 11, 2013, the Landsat 8 satellite rocketed into a sunny California morning onboard a powerful Atlas V and began its life in orbit. In the year since launch, scientists have been working to understand the information ...

Landsat 8 satellite begins watch

May 30, 2013

NASA transferred operational control Thursday of the Landsat 8 satellite to the U.S. Geological Survey (USGS) in a ceremony in Sioux Falls, S.D.

Recommended for you

Oceans of garbage prompt war on plastics

December 15, 2018

Faced with images of turtles smothered by plastic bags, beaches carpeted with garbage and islands of trash floating in the oceans, environmentalists say the world is waking up to the need to tackle plastic pollution at the ...

A damming trend

December 14, 2018

Hundreds of dams are being proposed for Mekong River basin in Southeast Asia. The negative social and environmental consequences—affecting everything from food security to the environment—greatly outweigh the positive ...

Data from Kilauea suggests the eruption was unprecedented

December 14, 2018

A very large team of researchers from multiple institutions in the U.S. has concluded that the Kilauea volcanic eruption that occurred over this past summer represented an unprecedented volcanic event. In their paper published ...

The long dry: global water supplies are shrinking

December 13, 2018

A global study has found a paradox: our water supplies are shrinking at the same time as climate change is generating more intense rain. And the culprit is the drying of soils, say researchers, pointing to a world where drought-like ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.