Saharan dust is bad for health. But it’s also crucial to Earth’s biology and climate

National Geographic | Jun 30, 2020 at 7:43 PM
  • The massive dust cloud arrived in Puerto Rico the Sunday before last, sweeping in and staining the evening sky a milky white.
  • Also, it’s carrying tons of lung-irritating fine particles toward North America, where chronic respiratory conditions are significant causes of disability and death.
  • So if a developing storm that’s growing upward in the atmosphere hits the dusty layer, the dry air helps snuff it out, like a flame robbed of the oxygen it needs to keep burning.