Laser Mapping Reveals New Details of Earth's Surface

Scientists get a three-dimensional Google Earth on steroids, which can penetrate forest canopies, chart sand dune movement, and more, thanks to radarlike lasers
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Mapping Movement

By comparing two detailed models created at different times, researchers can see in full color precisely how much each dune is moving and in what direction. Tracking the movement of sand can have especially important implications for areas of the globe that are under threat of desertification .....[ More ]

Waves of White

Three-dimensional images made with ALSM are able to capture the dune landscape within inches of its actual size and shape. Seen here, a computer-modeled image of the area might resemble a satellite photo , but it's rich in millions of thee-dimensional data points.....[ More ]

Shifty Sands of Time

White Sands National Monument in New Mexico is the largest expanse of gypsum dunes in the world. The 275 square-mile (700 square-kilometer) area has been a popular tourist destination since it opened as a federally protected site in 1934.....[ More ]

Demystifying the Mounds

ALSM is also being used to investigate mysterious Mima Mounds in central California. The California mounds, which resemble clusters in other states and countries, stretch over more than 15 square miles (40 square kilometers).....[ More ]

Ground Zero

Twelve days after the September 11, 2001, World Trade Center attacks , a team trained in ALSM from the University of Florida and personnel from Optech Inc., (a manufacturer of the equipment) began collecting aerial data of Lower Manhattan .....[ More ]

Following the Flood

In the midst of a flood last June, researchers mapped a large corridor of the Iowa River using ALSM. This image—to which color was added to distinguish water, vegetation, structures and land—provides much more data than a satellite image could.....[ More ]

Seeing the Forest (Floor) Through the Trees

Even the best areial mapping efforts have had to leave forest floors in the dark because they're generally obscured by the canopy. But ALSM mapping is able to peer through the foliage. The laser used in most of the mapping equipment has a near-infrared wavelength, which is reflected very well by the chlorophyll in plants.....[ More ]

Modeling the Mountains

Unlike traditional satellite images or aerial photos, airborne laser swath mapping (ALSM) creates three-dimensional models of the terrain below. How does it work? A small plane, equipped with an optical scanner, emits rapid-fire laser pulses (50,000 to 150,000 per second) that are reflected straight down in a zigzag configuration by a moving mirror.....[ More ]

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