NASA has released a fun video that shows Las Vegas's continuous sprawl. The video, which relies on images from one of NASA's Landsat satellites, captures in time-lapse nearly 40 years of growth. From 1972 to when the video ends in 2010, the Las Vegas metro area can be seen spreading westward across the desert as the city's population skyrockets from slightly under 300,000 to almost 2 million. NASA says the bright red areas of the video show healthy vegetation, mostly irrigated golf courses, while the gray areas are roads and buildings.
To demonstrate how the urban spraw of Las Vegas's occurred over a forty year time span.
ACTIVITY DESCRIPTION AND TEACHING MATERIALS
Watch Las Vegas Sprawl >>
TEACHING NOTES / CONTEXT FOR USE
When Landsat 5 launched on March 1, 1972, Las Vegas was a smaller city. This image series, done in honor of the satellite's 28th birthday, shows the desert city's massive growth spurt since 1972. The outward expansion of the city is shown in a false-color time lapse of data from all the Landsat satellites.
The large red areas are actually green space, mostly golf courses and city parks. You'll notice the images become a lot sharper around 1984, when new instrument designs improved the ability to resolve smaller parcels of land.
These Las Vegas images were created using reflected light from the near-infrared, red and green portions of the electromagnetic spectrum (Landsat 5 TM bands 4,3,2 and Landsat 1-3 MSS bands 4,2,1).
Landsat data have been instrumental in increasing our understanding of forest health, storm damage, agricultural trends, urban growth, and many other ongoing changes to our land resources. Studies using Landsat data have helped land managers keep track of the pace of urbanization in locations around the world.
REFERENCES AND RESOURCES
NASA and the U.S. Department of the Interior through the U.S. Geological Survey (USGS) jointly manage Landsat, and the USGS preserves a 40-year archive of Landsat images with free distribution of data over the Internet. The next Landsat satellite, now known as the Landsat Data Continuty Mission (LDCM) and later to be called Landsat 8, is scheduled for a launch in January 2013.