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Stronger winds send dust higher in the atmosphere, which can affect climate. Using lidar, CALIPSO builds vertical dust maps depicting slices of Earth’s atmosphere each map looks like a grimy window showing the concentration of African dust at different altitudes. With the benefit of spatial and temporal coverage, the satellite also helps NASA pinpoint the total mass of African dust leaving the continent. It’s commonly thought that Africa contributes more than half of global dust to the atmosphere, he said. With a global perspective, scientists can see where the world’s dust originates. “Satellites can provide routine sampling on a global scale,” said Hongbin Yu, a research physical scientist with the Climate and Radiation Laboratory at NASA Goddard Space Flight Center in Greenbelt, Md. Credit: Scientific Visualization Studio, NASA NASA’s CALIPSO satellite uses lidar to generate dust maps, which can show the concentration of dust at different altitudes. Although ground research sites like ATTO can study aerosol chemistry at a specific spot, CALIPSO provides an overhead understanding of aerosol (including dust) transport. Called CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation), the satellite records aerosols in three dimensions and maps the movement of aerosol clouds. In 2006, NASA launched a specific mission to focus on aerosols. Collectively, aerosol clouds (including clouds of smoke) can alter weather patterns and be visible from space. Individually, aerosols are rarely wider than a human hair. “Dust,” said Cassandra Gaston, an atmospheric chemist at the University of Miami, “has always been a big player in the climate system.” Aerosols at Altitudeĭust falls into the category of aerosols, small particles suspended in air.

Nutrients in tiny specks of dust may sound like minor contributions to the massive, complex ecosystems of the Amazon, but their effects are major.

Fires are also expected to change, further complicating the outlook for dust transport. Research indicates that these reliable conditions may change: Models show that North Africa is destined to get wetter, and a warming climate will shift existing wind patterns.

The phenomenon relies on two conditions: extremely dry soils and very strong winds.

The same material that gives the Sahara its dull beige tone in satellite images is the reason the Amazon stays so brilliantly green. Each grain of dust carries key nutrients like phosphorus and iron, and if the winds are right, those grains help fertilize the Amazon basin. Why do researchers make the trek? For many, it’s to study dust-not the fluffy stuff that collects under furniture, but the lightweight minerals swept up from the Sahara desert more than 5,000 kilometers away in North Africa. At the end sits ATTO, the tallest structure in South America, an orange-and-white spire 1 meter higher than the Eiffel Tower. Hours later, they clamber into a boat and head down the Uatumã River to reach another muddy road taking them deeper into the jungle. To reach the site, researchers drive several hours north from Manaus (the capital of Brazil’s state of Amazonas), then turn down a dirt road. The Amazon Tall Tower Observatory (ATTO) is exactly what it sounds like: a very tall tower, dotted with sensors, jutting above the canopy of the largest rain forest on Earth. Dust in the Wind, Dirt Under Our Feet, and Dunes of Another World