Dense clouds advancing over the Caribbean

In the course of the current week, an extensive cloud of dust from the Sahara will cover the Cuban archipelago, the western Caribbean sea and the southeastern United States and Mexico, said Doctor of Physical Sciences Eugenio Mojena López, a renowned specialist in the subject of the Institute of Meteorology.

According to the also Professor and researcher of said entity, belonging to the Environment Agency of the Ministry of Science, Technology and Environment (Citma), the models suggest that the values ​​of dust concentrations will be well above the levels normal, a factor that causes an appreciable deterioration in air quality.

Loaded with PM 10 and PM 2.5 particulate matter, highly harmful to human health, minerals such as iron, calcium, phosphorous, silicon and mercury, as well as viruses, bacteria, fungi, pathogenic mites, staphylococci and persistent organic pollutants, the referred Clouds are generated by the sand and dust storms of the Sahara and Sahel desert in Africa.

They can reach heights of three to seven kilometers, and once they are far from the African continent, a good part of them advance in a westerly direction, under the flow of the trade winds, spreading to Cuba, the southeastern United States, Mexico and Central America.

Dr. Mojena López specified that, although in general dust clouds begin to arrive in our country between March and April, the maximum days in such atmospheric conditions occur in June and July. The main feature that distinguishes its accentuated presence is the predominance of a dense haze, capable of limiting long-distance visibility, while the sky is shown in a milky hue.

Research carried out in the former Satellite Department of the Meteorological Institute, demonstrated the inhibitory effect of Sahara Dust on cyclogenesis in the tropical Atlantic basin, in particular, in the area between 10 and 20 degrees north latitude and 20 and 60 degrees west longitude.

As Professor Mojena explained, dust clouds create a very hot and dry air mass with low humidity values, which significantly hinders the emergence and development of tropical cyclones (ct), creating a hostile environment . Likewise, they increase vertical wind shear at height, preventing the system from concentrating energy for its formation and strengthening.

Hence, today they are increasingly recognized as a strong modulating factor of cyclonic activity in our geographic area, in addition to reducing the probability of precipitation in the areas under its influence.

Beyond largely conditioning the behavior of the weather, the Sahara Dust clouds cause negative impacts on human health and that of different marine and terrestrial ecosystems.

According to what Dr. Mojena López expressed, his presence has turned the Caribbean into a true corridor for asthma and other respiratory diseases, especially in people over 65 and children up to four years of age, in addition to promoting appearance of allergies and skin problems.

They also affect the decline of coral reef populations, by encouraging them to be attacked by an endemic fungus from Africa, transported by them, and contribute to the proliferation of so-called red tide events, associated with large blooms of algae, many of them toxic, and in the appearance of pests in rice, beans, fruit trees, sugar cane and other crops.