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Environmental Science

How Atmospheric Aerosols Shape Cloud Formation and Precipitation

Quick fact

A single cloud droplet typically forms around a microscopic aerosol particle called a cloud condensation nucleus; without such particles, clouds would require very high humidity to form, and they would rain far less.

Why this is interesting

You can likely recall that clouds form when water vapor condenses, but did you know that without tiny dust or pollution particles, most clouds would never form at all?