Estimated 43 Million Tons of Sahara Dust Falls into Caribbean Sea Annually, NASA

Every year, a staggering amount of dust from the Sahara Desert travels across the Atlantic Ocean and settles in the Caribbean Sea and the Amazon rainforest.

While Antarctica is often considered the largest desert on Earth, it's the Sahara that holds the title of the largest hot desert. The absence of liquid water, not the presence of sand, defines a desert. 

International Partnership to Study Atmospheric Particles

A survey conducted by the National Aeronautics and Space Administration’s CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations) satellite estimates that wind and weather, with their immense power, pick up on average 182 million tons of dust each year and carry it past the western edge of the Sahara at longitude 15W. This staggering feat of nature is a testament to the power of wind and weather.

CALIPSO is a partnership between NASA and the French Space Agency, CNES. The satellite surveys particles in Earth’s atmosphere over time and comprises three instruments:

• the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP Lidar),

• the Imaging Infrared Radiometer (IIR), and 

• the Wide Field Camera (WFC).

Although NASA and CNES agreed to end the CALIPSO science mission on August 1, 2023, scientists still have a lot of data to analyze as they examine each year's data to identify trends in Earth’s atmosphere. 

During its mission, NASA says CALIPSO delivered unprecedented measurements and mapped the structure of the Earth’s atmosphere for 17 years.

The Dust Cloud

Annually, a staggering amount of dust from the Sahara Desert travels across the Atlantic Ocean and settles in the Caribbean Sea and the Amazon rainforest. Atmospheric research by NASA estimates that 43 million tons of Sahara dust alone fall into the Caribbean Sea annually.

The agency estimates dustfall in the Amazon basin at 27.7 million tons annually—enough to fill 104,908 semi-trucks. Dust traveling from the African continent can affect people with respiratory problems, settle in stagnant drinking water, and coat sensitive equipment. 

Sahara dust has a few benefits in the western hemisphere. It provides marine ecosystems with essential nutrients, introduces fresh nitrogen and phosphorus to soil, and disrupts the formation of tropical cyclones in the Atlantic Ocean, the Caribbean Sea, and the Gulf of Mexico. 

The dust’s ability to ride weather patterns and disrupt the formation of tropical cyclones makes it an event scientists watch carefully to form more precise meteorological forecasts. In a 2020 issue of National Geographics, Alejandra Borunda writes about the Sahara Desert’s role in Earth’s biology and biodiversity.