(QCOSTARICA) After traveling more than 7,000 kilometers, a cloud of dust and sand from the Sahara arrived in Costa Rica. This phenomenon will keep the rains away for a day or two.
According to experts, it can affect those with allergies and asthma. It can also cause respiratory problems.
The amount of Saharan dust particles from the cloud that affects us since Tuesday is five times more intense than those recorded in other years, going from 40 to 200 micrograms per cubic meter.
That was the explanation by the scientist Daniel Poleo, from the National Meteorological Institute (IMN), who argued that the measurements are made with satellites, as well in different stations in the Caribbean Sea, the main one being in Puerto Rico, where they have confirmed that it is the largest in the last 50 years.
“It is because there are more intense dust storms in the Sahara desert. The amount of dust in the current cloud is 15.5 million square kilometers and 16 million tons,” said Poleo.
He added that this Friday the most intense phase is expected to arrive in Costa Rica and that is why they ask people with allergies or respiratory diseases not to go outdoors.
Between June and August, these dust storms are normal. The current one was strengthened by factors such as the warmer Atlantic Ocean than in other years.
#IMN_imagenes imagen del mediodía de hoy jueves muestra la masa de polvo del Sahara sobre Centroamérica y Costa Rica se percibe como una bruma blancuzca (fotos desde IMN) en el ambiente. Persiste el pronóstico que la mayor concentración de polvo será mañana viernes. pic.twitter.com/FuhUk0xxW6
— IMN, Costa Rica (@IMNCR) June 25, 2020
The fact that some regions of our country are more affected than others, is due to the fact that the lighter particles of the cloud rise to a maximum of 4,000 meters above sea level, which is why the Central Volcanic Mountain Range constitutes a natural barrier.
Heights such as that of Chirripó 3,820 meters above sea level or the Irazú volcano with 3,400 meters, prevent the passage of the largest amount of particles to the Pacific, thus affecting the Caribbean and the northern zone most.
The white haze that reduces visibility and clouds the mountains of the Central Valley is what filters through the La Palma pass, the Desengaño pass and other hollows between mountains.
The presence of this mass causes humidity and cloudiness to decrease, to generate a warm environment, slightly attenuated by the increase in winds.
For this year, as it is rainier, the effects of the veranillo de San Juan, a period of two dry days close June 24, was not expected to occur.
By chance, the presence of Saharan dust coincided with that date and since Tuesday, June 23 we see a significant reduction in rainfall.
According to the IMN, the presence of dust will be perceived the rest of the week.
For Sunday, the IMN expects the rains to return, as the dry effect of the cloud will have passed. In addition, on Sunday, tropical wave number 12 is expected.
However, Poleo said that behind that wave comes another less intense mass of dust from the Sahara, which is currently over Venezuela and that will arrive in Costa Rica sometime next week.
That dry mass will cut the rainy season again.