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A satellite image of dust blowing off the Sahara Desert in June 2020. (National Oceanic & Atmospheric Administration) A satellite image of dust blowing off the Sahara Desert in June 2020. (National Oceanic & Atmospheric Administration)

A satellite image of dust blowing off the Sahara Desert in June 2020. (National Oceanic & Atmospheric Administration)

Jeff Cercone
By Jeff Cercone July 13, 2023

Saharan dust clouds are regular occurrence, not a Bill Gates sun-blocking plot

If Your Time is short

  • Saharan dust clouds regularly make their way from North Africa across the Atlantic Ocean to Florida, especially during the summer months.

  • The clouds — masses of dry, dusty air kicked up from the Sahara desert and carried away by winds — are a naturally occurring phenomenon.

  • Bill Gates has not proposed blocking out the sun. He has donated to Harvard University researchers who are hoping to test spraying aerosols into the stratosphere, a solar geoengineering technology to combat climate change. That test was later called off.

Clouds of dust from the Saharan desert in North Africa crossed the Atlantic Ocean and in mid-July settled over parts of Florida, causing hazy skies and hot temperatures.

This is a regular occurrence, especially during the summer months, but some social media users are tying the dust clouds to philanthropist and Microsoft Corp. co-founder Bill Gates and an unrelated effort to combat climate change.

"Man says the sand storm headed our way is an attempt by Bill Gates to block out the sun," read a caption next to a video shared July 11 on Facebook.

In the video, a man on a split screen introduced another video featuring a man who he said has "an interesting viewpoint" about what the dust storm is going to be used for. "Of course, it’s going to be used by none other than Bill Gates," the first speaker said.

"We do know that this dust storm is not something that came from nature, OK? Nothing can happen in Africa and travel this far. I just don’t believe it," the first man said. 

In the second video, which came from a July 9 TikTok post, the speaker said Gates had proposed completely blocking out the sun to cool the Earth, and to do so he wanted to "chemtrail the sky." He said the current sandstorms have been "aimed at the United States."

This post was flagged as part of Meta’s efforts to combat false news and misinformation on its News Feed. (Read more about our partnership with Meta, which owns Facebook and Instagram.)

The Facebook video is wrong about both Gates and the recent Saharan dust clouds. 

Gates, a frequent target of conspiracy theories, did not propose blocking out the sun, as we explained in this 2022 fact-check.

Gates has donated to Harvard University’s Solar Geoengineering Research Program. Researchers there proposed a small-scale experiment called SCoPEx — short for Stratospheric Controlled Perturbation Experiment. They hoped to spray aerosols into the stratosphere from a high-altitude balloon in Sweden in 2021 to reflect sunlight back into space. That test was called off amid opposition from environmentalists, scientists and Indigenous groups.

These kinds of solar geoengineering technologies aim to reduce global warming with human-made interventions. They are controversial among scientists and outdoor experimentation is rare.

The White House on June 30 released a congressionally mandated report that supported studying the "scientific and societal implications" of the technology, but noted in a fact sheet that "there are no plans underway to establish a comprehensive research program focused on solar radiation modification."

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Meanwhile, Saharan dust clouds headed to the United States are a phenomenon that happens naturally and regularly, especially this time of year. 

They have happened for hundreds, perhaps thousands of years, said Jason Dunion, a University of Miami hurricane researcher working with the National Oceanic and Atmospheric Administration’s Atlantic Oceanographic and Meteorological Laboratory.

The laboratory uses satellites to track what it calls the Saharan Air Layer. It describes that as "a mass of very dry, dusty air that forms over the Sahara Desert during the late spring, summer and early fall."

During the peak season for Saharan Air Layer activity (late June through mid-August) outbreaks of dusty air emerge from the coast of Africa every three to five days and move over the tropical North Atlantic Ocean. They can travel thousands of miles across the Atlantic, to Florida and as far west as Texas.

A weather report from KHOU-11 in Houston said a Saharan dust cloud was expected to reach the area July 14. "This is nothing new," said meteorologist Cheetah Craft. "We see this happen every single year."

They don’t just reach the U.S. The Copernicus Atmosphere Monitoring Service said July 11 that a large "Saharan dust transport episode" was moving across Europe.

The warm, dry air and winds associated with the Saharan Air Layer can suppress hurricane formation and slow oceanic warming. Because the dust clouds can suppress thunderstorms, land below may see warmer temperatures, according to NOAA. The dust can also affect air quality, which can be a danger to people with asthma or other respiratory conditions.

Our ruling

A Facebook video claimed that Saharan dust clouds reaching the U.S. are part of an attempt by Gates to "block out the sun."

Gates has donated to Harvard’s Solar Geoengineering Program, where researchers had planned an experiment to spray aerosols into the stratosphere in Sweden to reflect sunlight, a technology proponents hope can battle global warming. The experiment, which would not "block the sun," was called off in 2021.

Saharan dust clouds are a naturally occurring phenomenon that have happened for thousands of years. They can regularly reach the U.S., as far west as Texas, and are common this time of year. 

We rate the claim False.

RELATED: Claim that Bill Gates is scheming to block the sun is wrong 

RELATED: Video of former CIA director is not proof that government is spraying sky with chemicals 

 

Our Sources

Facebook post, July 11, 2023

TikTok post, July 9, 2023

Jason Dunion, University of Miami hurricane researcher working with the National Oceanic & Atmospheric Administration’s Atlantic Oceanographic and Meteorological Laboratory, email exchange, July 12, 2023

WPTV-NBC 5, "Hazy and hot as Saharan Dust sweeps through South Florida," July 11, 2023

KHOU-11, "Saharan dust 2023 update: Plume expected to arrive in Houston Friday," July 12, 2023

Sun-Sentinel, "Three Saharan dust clouds targeting South Florida," July 11, 2023

Tampa Bay Times, "Dust from the Sahara Desert is bringing more heat to Tampa Bay," July 7, 2023

The Washington Post, "First major Saharan dust event reaches Florida. What it means.," July 11, 2023

The Washington Post, "This firm is working to control the climate. Should the world let it?," Jan. 9, 2023

CNN, "This controversial climate solution could be exactly what the planet needs. Or it could be a colossal disaster," Feb. 12, 2023

National Hurricane Center's Tropical Analysis and Forecast Branch, tweet, July 10, 2023

The New York Times, "Saharan Dust Blowing Across the Atlantic Could Reach South Florida," July 9, 2023

The New York Times, "Why the Snow in Parts of Europe Was Orange," March 27, 2018

The New York Times, "Test Flight for Sunlight-Blocking Research Is Canceled," April 2, 2021

KVUE-ABC, "Saharan dust brings hazy conditions to Texas," July 17, 2022

National Oceanic & Atmospheric Administration, "The Saharan Air Layer: What is it? Why does NOAA track it?" May 20, 2022 

National Oceanic & Atmospheric Administration, Atlantic Oceanographic & Meteorological Laboratory, "The Saharan Air Layer," July 12, 2023

Copernicus Atmosphere Monitoring Service, "CAMS forecasts show large Saharan dust transport heading for southern Europe," July 11, 2023

The White House, "Congressionally mandated research plan and an initial governance framework related to solar radiation modification," June 30, 2023

The White House, "Congressionally-Mandated Report on Solar Radiation Modification," June 30, 2023 

Keutsch Group at Harvard, "SCoPEx: Stratospheric Controlled Perturbation Experiment ," accessed July 12, 2023

Harvard’s Solar Geoengineering Program, "Funding," accessed July 12, 2023

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Saharan dust clouds are regular occurrence, not a Bill Gates sun-blocking plot

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