Dust off the Sahara fertilizes the Atlantic Ocean and American soils. The good news is it can blunt tropical storms, but it also feeds red tide, the Sargassum seaweed that piles up on our beaches every summer and other harmful algae blooms. Some 60 million tons of the Sahara's nutrient-laden mineral dust lofts into the atmosphere annually, according to NASA , creating a massive layer of hot, dusty air that whisks across the Atlantic with the winds to deliver those nutrients to the ocean and plants in the Caribbean and South America.
In heavy doses near ground, the dust fouls air quality. The storm comes a year after NASA documented the largest dust storm in two decades of observations. Saharan dust covered the Caribbean Sea in June , dimming skies over several southeastern states. The Caribbean low-level jet, along with the subtropical high, can further transport the dust from the Caribbean region towards the States. Dear Abby Horoscopes Lifestyles Music. View Obituaries Place an Obituary Celebrations. Home Drive Working.
Reddit Pocket Flipboard Email. National Oceanic and Atmospheric Administration. Thanks for signing up! Check your inbox for a welcome email. Email required. Additionally, dust also stabilises the atmosphere. Some of the dust even reaches the Amazon region of South America, where experts say that minerals it contains, such as iron and phosphorus act as a fertiliser.
Join thought-provoking conversations, follow other Independent readers and see their replies. Satellite instruments showed that the cloud was far denser with dust particles than previous events. This was an extreme outlier. On the ground, the dust cloud, dubbed Godzilla , is triggering air quality alerts for millions of people. The first intense plume is now on its way out of the United States, but another, thinner cloud of Saharan dust is on the way this week.
The Saharan dust is a prime example of the complicated forces that tie our planet together and how the things we experience at home can start from far away. The dust behind the recent clouds originates at the convergence of two ecosystems: the Sahara and the Sahel.
The hot, dry Sahara in North Africa is the largest desert in the world outside of the poles. The Sahel is the stripe of land just south of the Sahara with a more tropical climate.
Over half the named storms that we get each year are coming from this nursery over the Sahel, just south of the Sahara. There, convective storms in the early summer whip the dry ground and loft particles of silica, iron, and phosphorous as high as 20, feet into the sky.
When this airborne dust and dry air floats off the coast of West Africa, it forms the Saharan Air Layer , a segment of the atmosphere that moves across the North Atlantic Ocean every three to five days from the late spring through the early fall. And number two, it held together all the way across [the Atlantic Ocean]. Ordinarily, this dust would start to thin as it approached the Americas, with some falling into the ocean along the way.
But there was so much dust picked up recently that even after this thinning process, a lot made it across the Atlantic. Researchers are still unclear as to why the recent Saharan dust cloud was so intense since there are so many factors at play. Seftor said it may have to do with the intense rainfall in the Sahel region in May and June. That in turn may have fueled local weather to whip up more dust.
But he cautioned that this is just speculation at this point. Another culprit could be strong tropical waves.
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