Sahara Dust That Protects Against Hurricanes Dissipating As Storm Season Ramps Up

The "Godzilla-sized" Sahara Dust Cloud from Africa that traveled 5,000 miles over the Atlantic Ocean into the southern states this summer not only caused incredible sunsets and breathing problems—it also prevented hurricanes from forming.

But now that we're reaching the peak of hurricane season, the dust cloud is starting to dissipate, and signs suggest that serious hurricanes are on the way.

The Sahara Dust Cloud, also known as the Sahara Dust Layer, helped create a 24-day lull in hurricanes from June 10 to July 4, according to National Oceanic and Atmospheric Administration hurricane scientist Jason Dunion. During this period, the dust layer helped slow down winds and cool oceanic waters, two atmospheric conditions needed to make a hurricane.

The cloud covered "an area larger than the 48 contiguous states," Weather Channel meteorologist Carl Parker wrote in an email to the Tampa Bay Times. But now the dust cloud is shrinking, and with it, its power to stop hurricanes.

The cloud helped soak up the moisture, warm sunlight and slow down the oceanic winds that all contribute to the formation of hurricanes. It created 20- to 60-mile per hour winds that slowed down the potential hurricane winds. And by stopping sunlight from evaporating ocean water, the sand cloud also stopped cyclone clouds from forming.

Tropical Storm Gonzalo in July was expected to become a hurricane, but the dust cloud weakened it before it even reached the Caribbean islands. The same things are believed to have happened with Hurricane Isaias, downgrading from a Category 1 hurricane to a weaker tropical storm as it approached Florida in late July.

While what remains of the Sahara Dust Cloud could still help weaken August and September storms, its preventative power has lessened, leaving stronger cyclones to develop.

Sahara dust layer hurricane season storms dissapate
The Impact of the Sahara Air Layer (SAL) on Venezuela. Saharan dust inhibits development rains, reduced visibility and increased feeling of warmth. Elizabeth Fernandez/Getty

Last week, the National Oceanic and Atmospheric Administration's Climate Prediction Center said that warmer water in the Atlantic and weaker wind sheer—cross-winds that oppose the main winds' direction—will create an "extremely active" hurricane season.

One prediction from Colorado State University said the next four months could have 10 hurricanes. This year there have already been nine hurricanes—in a typical year, a ninth hurricane doesn't come until the start of October.

While the Sahara Dust Cloud also provides much-needed nutrients to plants and animals in the Amazon basin, its effects aren't entirely positive. It can contribute to "Red Tide" algae, which are harmful to sea life and also cause poor air quality and serious respiratory issues, exacerbating symptoms in those who are already struggling with breathing issues or the COVID-19 coronavirus.