Dust interacts with clouds, oceans, and the sun's radiation as it is a key component of Earth's climate. Overall, it impacts the living organisms on our planet and affects everything from weather and rainfall to global warming.
One of the two types of dust in the atmosphere is the fine dust that cools our atmosphere because it scatters sunlight just like what the clouds do. The second one is the coarse dusts which are larger and originates from places such as the Sahara Desert. The dust tends to be warm just like the greenhouse gases.
It is important to know the amount of coarse dust in our atmosphere to understand atmospheric phenomena and to know the degree coarse dust is affecting the planet's temperature.
More than ever before
UCLA scientists report in the journal Science Advances that there is four times the amount of coarse dust in Earth's atmosphere than was previously believed which can affect atmospheric phenomena like hurricanes.
They found that the atmosphere of Earth contains 17 million metric tons of coarse diet. That is roughly 17 million elephants or the mass of every American put together.
The study's first author, Adeyemi Adebiyi, a postdoctoral researcher in the Department of Atmospheric and Oceanic Sciences in UCLA and University of California President's Postdoctoral Fellowship recipient said that climate models must include an accurate treatment of coarse dust in the atmosphere to properly represent its impact on the Earth system.
Adebiyi added that through plugging the amount of missing coarse dust into models it increases the likelihood that the net amount of fine and coarse dust is warming rather than cooling the climate system of the Earth, from air to oceans.
Coarse dust particles absorb both incoming radiation from the sun and outgoing radiation from the Earth's surface making the entire climate system of Earth warm. These particles may affect the stability and circulation within our atmosphere that in turn can impact atmospheric phenomena, as reported by Archaeology News Network.
Jasper Kok, a UCLA atmospheric and oceanic sciences associate professor, said that they found a drastic difference with the results of their research and with what is predicted by the present climate models upon comparing the two.
"State-of-the-art climate models account for only 4 million metric tons, but our results showed more than four times that amount," said Kok.
Dust particles do travel
The findings of the research also showed that dust particles are eventually deposited further from their source because particles stay in the atmosphere longer. For example, dust particles blown from Sahara could reach as far as the Caribbean or the United States.
Dust particles that end up in oceans stimulate the ocean ecosystems' productivity and increase the amount of carbon dioxide it absorbs.
According to Adebiyi, climate models have been invaluable tools for scientists but it underestimates the effect of coarse dust on critical aspects of the Earth's climate system when it missed detecting most of the coarse dust in the atmosphere.
