Extreme Weather Event: Saharan Air Layer Outbreak


Christopher Owen

African dust plumes, that blow across the Atlantic Ocean, are common this time of year. From late spring to early fall, these plumes of dust travel 5,000 miles from the African coast westward by easterly winds over the Atlantic, Caribbean, and Gulf of Mexico. But one that is denser than in the past 50-60 years (nicknamed “Godzilla” for its gargantuan size) has been detected by the VIIRS instrument onboard NASA-NOAA’s Suomi NPP Satellite and may be noticed in different parts of the U.S. this week. Especially in the Southern U.S., the tropical blue sky will become hazy. But sunsets and sunrises will be amplified because the dust particles cause sunlight to reflect light, producing deeper orange and red colors. 


The dust plumes, which contain hundreds of millions of tons of dust can be beneficial to the environment by fortifying beaches in the Caribbean and fertilizing soils in the Amazon. The plumes can also help suppress hurricane formation because they contain really dry air, wind shear from strong mid-level winds, and dust particles. This is important to meteorologists as peak hurricane season runs from August to October. However, the plumes can also unfortunately carry harmful pathogens (like bacteria) and degrade air quality and human health. For most people, the dust will mainly be a nuisance, but for others with respiratory issues or Covid-19, the plume could be more problematic.