particle

These polar "geoengineering" techniques aim to cool the planet in unconventional ways, such as artificially thickening sea-ice or releasing tiny, reflective particles into the atmosphere.

The Northern Lights are caused by solar winds carrying charged particles interacting with the earth's magnetic field.

Rico said it’s a hot spot where the falling water forms bubbles that burst and send fine particles of pollutants into the air.

When averaged over the year, Imperial Valley and Salton Sea Basin have twice the state limit for larger particles.

“The concern was that in large concentrates the particles would be hazardous. But the cloud has since dissipated.”