The desert dust storms of the African desert crossing the Atlantic
The desert dust storms of the African desert crossing the Atlantic are not new, but the current dust storm was very large and NASA satellites looked at the huge column in June. NASA’s NOAA Suomi NPP satellite showed that the dust cover had moved over the Gulf of Mexico and spread to Central America and part of the eastern Pacific Ocean.
NASA uses satellites and other resources to track aerosol particles made of dust, smoke and volcanic ash from the desert. The Suomi NPP on-board Suible NPP Visible Infrared Imaging Radiometer Suite (VIIRS) provided an ozone image while the Nadir-Mapper (NM) Ozone and Stylistics (NPS) Ozone Mapping Tool on the Suomi-NPP satellite provided the absorption of aerosol index values. OMPS indicates the presence of aerosol particles absorbing light (ultraviolet (UV) – particles absorbing air) such as desert dust. The absorbed aerosol index is related to the thickness and height of the aerosol layer.
The aerosol absorption index is useful for identifying and tracking the long-range transport of volcanic ash from volcanic eruptions, smoke from forest fires or biomass burning events, and dust from dust storms of the desert. These parts of the aerosol can be drawn above clouds and snow-covered areas.
Colin Softfor, atmospheric scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, created images from the Sui NPP OMPS aerosol index and visual images from VIIRS. Yucatan Peninsula, across the Gulf of Mexico and into South Texas. “At this point the situation becomes more complicated because the signal for an absorbed aerosol index seen further north to Texas, Oklahoma, Nebraska, etc., may be a mixture of dust and smoke from the many fires in the southwestern United States. This dust traveled over Central America. It left for the East Pacific. ”
On June 25, animations combining the OMPS aerosol index and VIIRS visual images from the NASA / NOA Suomi NPP satellite were created at NASA Goddard to illustrate the movement of the desert dust cloud from 15 to 25 June 2020. The animation showed a column of dust from the west coast of Africa on the Atlantic Ocean to the Caribbean Sea and more across the Gulf of Mexico on certain Gulf countries.
Aerosol particles absorb and disperse incoming sunlight, reducing visibility and increasing optical depth. Aerosol particles have an effect on human health, weather and climate. Aerosol particles are produced from many events, including human activities such as factory pollution and natural processes such as fire smoke, dust from dust storms, sea salt from broken waves and volcanic ash from volcanoes. Aerosol particles affect human health when they are inhaled by people with asthma or other respiratory illnesses. Aerosol particles also affect weather and climate by cooling or heating the Earth and improving or preventing the formation of clouds.
On June 18, NASA’s Earth Observatory noticed that the thickest parts of the column appeared to extend 2,500 kilometers (1,500 mi) across the Atlantic Ocean. On June 24, the column spanned more than 5,000 miles.
Dust from Africa can affect air quality as far as North and South America if it is mixed at ground level. But dust can also play an important environmental role, such as fertilizing the soil in the Amazon and building beaches in the Caribbean. The dry and hot conditions and winds associated with the stratification of the desert from Africa can also prevent the formation and intensification of tropical cyclones.
“Although the transfer of dust from the desert across the ocean to the Americas is not common, the size and strength of this particular event is unusual,” said Softtor. “Also, if you look away from the coast of Africa, you can see another big cloud coming from the continent, and it continues to fuel the long chain of dust that crosses the Atlantic.”
report by Siencedaily