Researchers studied almost twenty years of satellite and reanalysis data to see how tiny particles in the air, called aerosols, change clouds and sunlight. They looked at particles from pollution, wildfires and a volcanic eruption.
They found opposite trends in the two hemispheres. Cleaner air in the Northern Hemisphere let more sunlight reach the surface. In the Southern Hemisphere, big wildfire smoke and volcanic particles made clouds brighter and sent more sunlight back to space.
Because these effects work against each other, aerosols had little net global influence on the recent rise in Earth’s heat imbalance.
Difficult words
- aerosol — very small particles that float in airaerosols
- reanalysis — analysis that uses past weather data and models
- hemisphere — one half of Earth, north or southhemispheres
- wildfire — a large outdoor fire in forests or fieldswildfires
- volcanic — related to a volcano or its activity
- heat imbalance — when Earth gets more or less heat than normal
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- Do you think cleaner air is good for people in your country? Why?
- Have you ever seen smoke from wildfires or a volcano? What did the sky look like?
- How do brighter clouds change the amount of sunlight that reaches the ground?
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