The Sahara desert, the world’s largest desert, fertilizes the Amazon rainforest, also the world’s largest, according to atmospheric scientist Hongbin Yu, the lead author of a study by NASA’s Goddard Space Flight Center.
Relying on satellite data, NASA recently released an estimate of how much phosphorus is in the dust that travels from the Sahara to the Amazon basin.
Each year, million tons of phosphorus-laden dust gets blown from the Sahara, more specifically from an ancient lake bed called the Bodele Depression in Chad, to the Amazon by strong winds.
About 182 million tons of dust, enough to fill 689,290 semi-trucks, are carried across the Atlantic Ocean, where about 27.7 million tons of dust, enough to fill some 104,908 semi-trucks, fall atop of the Amazon.
Phosphorus is essential to the growth of plants, which the Amazon depends on in order to flourish.
Most of the Amazon’s phosphorus is washed away by rain into streams and out of the forest, but the amount lost, roughly 22,000 tons, is made up for by the dust from the Sahara desert.
The pattern of dust transported annually is highly variable. Scientists believe this variation could have been affected by high rainfall in the Sahel region, the long strip of semi-arid land on the southern border of the Sahara.