The Sahara is the world’s largest desert. At more than 7 million square kilometers ( 3 million square miles) it is almost the size of the continental United States.
Dust from the Sahara is carried on a 4800 km (3000 mi) journey across the Atlantic where a portion of it lands in the Amazon Basin, home of the largest rainforest on the planet.
The dust plumes can be seen from space and have now been 3D-imaged by NASA’s Calypso satellite.
On average, 165 million metric tons (182 million U.S. tons) of dust leave the Sahara each year and of this amount, about 25 million metric tons (27 million U.S. tons) are deposited in the Amazon Basin.
What is in this dust that is so precious to the Amazon? The answer is Phosphorus. A remnant from the desert’s past as an ancient lake bed, rock minerals composed of dead microscopic organisms are loaded with phosphorus. Phosphorus is an essential nutrient for plant protein formation and growth.
Nutrients are in short supply in Amazon soils. Fallen decomposing plant matter provide the majority of nutrients to the plants and trees living there but some nutrients like phosphorus are washed away by rainfall into streams and rivers, draining from the Amazon Basin like a slowly leaking bath tub.
The phosphorus that reaches Amazon rainforest soils from the Sahara dust (an estimated 25 million metric tons each year ) is about the same amount that is lost from annual rains and flooding.
Dust from deserts is an essential component of the earth’s global ecosystem. Every place plays its valuable part.
Mother Nature is truly awe inspiring. We mustn’t fuck with her.