55%—The amount that atmospheric desert dust has increased globally since preindustrial times, according to new research published in Nature Reviews Earth & Environment that also found the increasing dust levels have a slight cooling effect on Earth. Researchers utilized satellite and ground data to calculate that there are about 26 million tons of microscopic mineral particles in the air globally. They then used data taken from ice cores, peat bogs, and marine sediment records from around the world to distinguish the layers of atmospheric dust that had fallen, which revealed the global increase in desert dust, largely originating from Asia and North Africa. The reason for the greater amount of desert dust is not clear, and the researchers found the increase was not linear. The study is the first to quantify the cooling effect of increasing levels of desert dust, finding that since the mid-1800s it could have concealed up to 8% of Earth’s warming in climate projections. “By adding the increase in desert dust, which accounts for over half of the atmosphere’s mass of particulate matter, we can increase the accuracy of climate model predictions,” notes lead author Jasper Kok of the University of California, Los Angeles. [Source: University of California, Los Angeles]
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