Saharan Dust Delivers 22,000 Tons of Phosphorus to Amazon Each Year
Updated
Updated · spacedaily.com · May 20
Saharan Dust Delivers 22,000 Tons of Phosphorus to Amazon Each Year
4 articles · Updated · spacedaily.com · May 20
27.7 million tons of Saharan dust reaches the Amazon Basin annually, carrying about 22,000 tons of phosphorus—roughly enough to replace what the rainforest loses each year to heavy-rain runoff.
NASA-backed satellite measurements over 2007-2013 quantified the trans-Atlantic flow: about 182 million tons leaves the Sahara’s western edge each year, 132 million falls into the Atlantic, and 24 million continues to the Caribbean.
That nutrient matters because Amazon soils are old, heavily weathered and chronically phosphorus-poor, making outside replenishment critical to long-term plant productivity.
The main dust source remains disputed: early studies pointed to Chad’s Bodélé Depression, but a 2020 analysis argued much of that dust rains out before crossing the Atlantic and highlighted El Djouf in western North Africa instead.
Researchers say the broad link is now well established even as source details remain unsettled, underscoring that the Amazon’s nutrient cycle depends on climate-driven processes in another continent.
As climate change alters the Sahara, will its life-giving dust become a more potent driver of global warming?
Could international efforts to stop desert dust in Africa unintentionally starve the Amazon rainforest of its essential nutrients?
Scientists still debate the true Saharan origin of the Amazon's fertilizer. Why is solving this mystery critical for its future?
Trans-Atlantic Dust Highways: 28 Million Tons of Sahara Dust Replenish the Amazon Each Year
Overview
The Amazon rainforest depends on a remarkable natural process: each year, vast quantities of dust travel from the Sahara Desert across the Atlantic Ocean. This dust is rich in vital nutrients like phosphorus, acting as a crucial lifeline that replenishes the Amazon’s soil and supports its immense ecosystem. Recent scientific findings have provided unprecedented detail, confirming the scale and significance of this trans-Atlantic nutrient transfer for the rainforest’s long-term health. For the first time, scientists have precisely quantified the sheer volume of dust making this journey, highlighting its essential role in sustaining the Amazon.