NASA satellite sees dust plume from Sahara Desert over Atlantic Ocean
Dust clouds have never looked so good.
July was a particularly windy month in Africa Sahara desert, with large plumes of dust being drawn across the Atlantic into the United States and the Caribbean. And NASA’s Aqua satellite was aware of the show.
Using its Moderate Resolution Imaging Spectroradiometer (MODIS), the satellite captured this natural-color image of a massive dust plume swirling off the Sahara above the ocean, stretching between the islands Canary Islands and Cape Verde. Aqua is part of the international Earth Observation System (EOS) and studies the water cycle.
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Although this specific image was taken on July 26, Aqua and other satellites captured many similar events throughout the month, indicating a more active month than normal. But Sahara dust plumes are common – some 182 million tons of dust cross the Atlantic every year — and they play an important role in the Earth’s climate system.
As they travel through the air, dust particles absorb and reflect sunlight. This helps the planet’s overall thermal regulation – and it also creates spectacular sunsets, which have been seen across Florida, Texas and the Caribbean over the past month.
Dust plumes also affect cloud cover and the formation of storms, especially hurricanes. “Not only [the dust plume] contain dry air, but there is usually a layer of high wind shear (opens in a new tab) associated with. Hurricanes hate both of those things,” said University of Miami meteorologist Brian McNoldy. told NASA (opens in a new tab).
Increased dust plumes in July may have contributed to the current calm hurricane season. To date, there have only been three named storms in the Atlantic, about 41% of the average. “It’s calm, but things can change in the blink of an eye with just one hurricane,” McNoldy said. “If we are still 41% of the average at the end of September, it would be a sure sign of a calm season.”
Dust not only plays a role in the Earth’s climate, but also in its biological systems. It acts as a kind of fertilizer – the minerals in the dust, such as iron and phosphorus, are crucial for plants and phytoplankton. Saharan dust, in particular, blows towards the Americas and is responsible for providing nutrients to places rich in biodiversity like the Amazon rainforest.