A massive plume of hazardous dust is heading towards the US East Coast, and millions have been warned to prepare for air quality alerts and breathing issues.
Saharan dust is exactly what it sounds like – a cloud of sand and dirt blown west across the Atlantic Ocean by strong wind currents passing over Africa.
The winds take the contents of the Sahara Desert into the atmosphere, where they travel towards Florida, the US Gulf Coast and the Caribbean, bringing days of hazy skies, lower rain chances and air quality concerns for those with preexisting health problems.
A 3,000-mile-long plume of Saharan dust has been spotted by meteorologists in the Southeast, and the latest forecasts expect the dust to arrive in South Florida by Monday.
While the dust will likely keep tropical storms and hurricanes from forming in the Atlantic, the plume also carries hazardous materials called fine particulate matter which can inflame the lungs and exacerbate conditions like asthma and COPD.
The fine particulate matter (PM2.5) in Saharan dust is mainly composed of mineral particles lofted from the desert.
That includes clay, quartz, feldspars and iron oxides – which give the dust its reddish color and create stunning sunsets when this dust is in the air.
However, when these particles begin falling to the surface, PM2.5 is small enough to penetrate human tissue and cause breathing issues with prolonged exposure. It also raises the risk of heart attack, stroke and premature death for those with a history of heart disease.
A 3,000-mile-long cloud is traveling from the Sahara Desert to the US this weekend
Although the plume will impact air quality, it can also create stunning sunrises and sunsets, adding a warm, colorful glow to the sky
Forecasters in Florida noted that this plume of Saharan dust is moving toward the US unusually late in the year.
Typically, these clouds arrive in early summer, between late June and mid-August. However, meteorologists have previously noted that the world’s weather patterns have been upended by the emergence of El Nino in the Pacific Ocean.
This tends to flip global climate patterns, keeping the Atlantic cooler with stronger winds that cut down hurricanes before they have a chance to form.
The densest portion of the Saharan cloud is expected to impact the Caribbean starting this weekend, affecting residents and tourists in Puerto Rico, the Dominican Republic and even as far west as Cancun, Mexico.
Officials with the National Weather Service monitoring Puerto Rico warned: ‘High to locally very high concentrations of Saharan dust will spread across the region later today and persist through Sunday, bringing hazy skies, reduced visibility, deteriorated air quality and drier conditions.’
While Saharan dust typically sends waves of sand and dirt towards the US, it can also lift trace metals and harmful biological material such as bacteria and fungi into the air.
This is more typically seen in the Southwest, where so-called ‘fungal storms’ pick up the microscopic fungus known as Coccidioides from local soil – triggering cases of the potentially fatal lung infection Valley fever when inhaled.
In 2020, Penn State University Professor Gregory Jenkins told AccuWeather: ‘Not only are asthmatics going to suffer more, but if there are pathogens on that dust, the number of respiratory infections could go up.’
Meteorologists have noted that Saharan dust hinders the development of hurricanes
Jenkins’ concerns were specifically tied to the Covid-19 pandemic at the time, however, studies have shown that PM2.5, fungi and even industrial pollutants can be carried by Saharan dust plumes.
A report in the Journal of Clinical Medicine found that Saharan dust reaching the US raised levels of PM2.5 in Miami by as much as 25 percent.
The study, which monitored patients with COPD – a long-term lung condition where the airways become narrowed or damaged – revealed that Saharan dust plumes multiplied the odds of a COPD flare-up by nearly five times.
Study authors from the University of Miami warned: ‘Dust storms impact large areas and have a widespread effect. For example, Saharan dust affects most parts of southeastern US, including Florida and Texas.’
‘Transported dust may not only impact respiratory diseases, but other diseases as well, including allergies and immunological disorders,’ they continued.
‘Therefore, intensifying dust exposure is likely to have a heavier effect on human health, which warrants proactive dust exposure management strategies to mitigate these adverse health effects.’
