According to Cuban meteorologist José Rubiera, the gigantic sandstorms that occur in the central zone of the great Sahara Desert located a little more than 7,000 kilometers east of the Caribbean Sea, beginning in March and April, have their greatest expression in June and July, sometimes reaching August and, to a lesser extent, September.
They are not really clouds, he added, but areas of dust concentration called Saharan dust clouds. The dust is composed of very fine particles, and rises in the atmosphere from 1.5 to almost six kilometers high, he added.
Surrounded by the very dry air of 30 percent relative humidity or less, it is driven by wind currents and begins its journey across the tropical Atlantic Ocean and the Caribbean, often reaching Central America, the Gulf of Mexico, southeastern United States, or northeastern Mexico.
A Sahara dust cloud can transport over the Atlantic around 28 million tons of such particles, and each year amount to hundreds of millions of tons, he said.
According to the scientist, it is estimated that the intensity of the Sahara dust layer has increased since the 1970s, due to longer periods of drought in the African Sahel area, and the occurrence of more sandstorms.
As the air accompanying the Saharan dust is so dry, it inhibits the formation and development of tropical waves and tropical cyclones, which is in line with the behavior of these weather systems during this period, he said.