Although the Sahara Desert zone was not "stuck" with South America between the Paleozoic and Mesozoic periods when the supercontinent Pangaea existed, in these times that we live this African region provides the countries of South America, the Caribbean, Central America and Mexico with the dust of its surface.
That "powder", rises in the atmosphere and is able to travel over the Atlantic Ocean and is deposited in our countries.
The north wind, the North Trade Winds, brings this material and it accumulates as part of the soil or as dunes. I was told at sorprendí́ that the dunes on the Venezuelan coast were a product, especially of the dust from the Sahara. It is incredible that in the graphs taken from the satellites you can see it.
This phenomenon is called S.A.L. because of its English acronym: Sahara Air Layer, which translates into Spanish as Capa de Aire del Sahara, so it should be better known as C.A.S.
From the point of view of meteorology, science that studies the meteors or atmospheric phenomena, this cloud of dust is called calima and its effects are studied with interest within the subject of environmental health, because it can affect the airways in an acute way and exacerbate chronic lung diseases (chronic bronchitis, pulmonary emphysema, asthma, bronchiectasis, pulmonary fibrosis, others).
Humanity's adaptation of ecosystems for the development of models of ecosystems called cities, often deprives them of trees, developing housing, parks, streets and avenues without trees, leaving them "naked" to the heat and wind and if the dust of the Sahara comes, we are at the mercy of the phenomenon S.A.L or C.A.S.
The trees serve us as a windbreak and a filter for the lime. If we shed trees because they are a source of "dirt" (they say this because of their dry leaves), because they break the floors (because they were badly planted and/or didn't get water and their roots come out to get it), because people or their vehicles take over their shadows), we pay the consequence of dispensing with their services.
The green windbreaks and green curtains is a natural use tool, is to use the trees to protect us from the wind and the heat. The mangroves on the coast offer this curtain service, because they protect us from the winds, storms, thunderstorms or "hoses" and other oceanic, marine and lake cyclones, in addition to the dragging effects of the tidal waves.
Trees are used in agriculture to protect crops from the mechanical effect of winds, in the form of rows to make a barrier "perpendicular" to the direction of the wind, así́ continues to say the agronomist Ivana Amico, who increases production by more than fifty percent if she uses these windbreaks.
Given this evidence, the only thing left from the point of view of environmental health is that the presence of trees in our homes reduces the effect of the winds and the heat on our respiratory system. This translates into health and the prevention of acute respiratory disease and the loss of memory of our relatives who suffer from these chronic respiratory diseases.
In addition, in the face of this COVID-19 pandemic, getting sick from our respiratory system would make us nervous, but we would also be vulnerable to the presence of the Coronavirus because we would be injured.
The manifestation of the Sahara Air Layer (S.A.L. for its English acronym or C.A.S. for its Spanish acronym), reminds us that removing trees from the city, especially from my community and my home, gives us a risk factor for respiratory diseases. All that remains is to recommend planting trees in our homes, in our communities, in our cities.