How Worried Should We Be About the Saharan Dust Cloud’s Arrival?
2020 has brought us massive wildfires, the coronavirus pandemic, civil unrest and murder hornets. And now, for the planet’s next act? A giant Saharan dust cloud nicknamed "Godzilla" is traversing the globe. This unusually large phenomenon threatens to envelop the sky around us with dust and other particulate matter that can impact our health.
Every year a thick plume of dust forms from sand in the Sahara desert. The 2020 version of this event has turned out to be quite extreme, however — much like other events that have taken place this year — stretching 4,000 miles and alarming scientists. With everything frightening and tragic that’s been crammed into the first few months of this decade, many of us may be experiencing worry fatigue. But is this latest atmospheric abomination something that really deserves our concern?
The Saharan Air Layer’s Role
To understand the origins of the dust cloud, let’s start with the Saharan Air Layer (SAL). This is a particularly hot, dry and dusty layer of the atmosphere that originates from the Sahara Desert in North Africa. It contains sand, mineral dust, particulate matter and other detritus from the surface of the desert that gets kicked up and carried away in the air. As pressure systems move through the desert picking up sand and other particles, this layer grows in height, sometimes extending 20,000 feet into the sky.
Where Does the Saharan Dust Cloud Travel — and Is It Always Bad?
To best imagine how the dust cloud travels, visualize a large ring of air hovering several thousand feet above the North Atlantic Ocean with the equator as its lower boundary. It doesn’t touch down on land, and the winds within it travel in a clockwise motion but aren’t totally continuous. This pressure system is constantly moving and swirling along its semi-circular path, which exists above countries like Morocco, Mauritania, Spain’s Canary Islands, Puerto Rico, Cuba, various Caribbean islands and the United States’ Gulf Coast and eastern seaboard. This, too, is the path that the Saharan Dust Cloud follows as it’s propelled along by the pressure systems. The distance inward that it travels into the United States depends on its size. This summer, multiple plumes are expected, some of which are expected to travel as far west (or farther) as the Great Plains states.
2020's Godzilla-sized Dust Cloud
This year's Saharan Dust Cloud is potentially the largest ever on record, thus the Godzilla nickname, and experts have referred to this historic concentration of dust as the "largest in 50 years." It’s certain to be "the most extreme out of all dust-related weather events" this year as well, with aerosol-particle concentrations sitting at the highest levels researchers have ever measured. As a result, air-quality levels in areas where the plume travels are being reduced to hazardous levels. Fog-like hazes are forming, turning daylight into virtually night-like conditions. Visibility problems have been reported in many cities and are creating particularly difficult issues at airports, causing closures and grounding flights.
How Does the Dust Cloud Impact Human and Environmental Health?
The pollution that the Saharan Dust Cloud produces is similar to other forms of air pollution. One pressing concern is the particulate matter that the cloud carries — and that people breathe in. The World Health Organization (WHO) states that environmental pollution from particulate matter is responsible for 1.4% of all deaths worldwide. While more studies are needed to demonstrate consistent results, the WHO has linked Saharan dust in particular to increased incidence of cardiovascular disease, respiratory illnesses such as asthma and some infectious diseases, along with elevated overall mortality.
Should We Be Worried?
The size of this year's dust cloud is a concern. As a result of its size and the distance into the United States it’s expected to travel — coupled with the fact that the first cloud has already made its presence known by reducing air quality along the Gulf Coast — there’s little doubt that the arriving clouds will continue affecting air quality in some places. It’ll likely drop to hazardous or near-hazardous levels, driving negative effects on human and animal health in the process.