Dark Skies: Volcanic Contribution to Climate Change

Volcanoes

Mount St. Helens, May 1980

http://vulcan.wr.usgs.gov/Volcanoes/MSH/Images/

Mount St. Helens, May 1980

http://vulcan.wr.usgs.gov/Volcanoes/MSH/Images/

Compare and Contrast Images

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Layer of fine dropletsfollowing the Pinatubo eruption

Pristine Atmosphere

Volcanic Contribution to Climate Change

Step 1

Ash and gas enter the atmosphere

Volcanic Contribution to Climate Change

Step 2

Ash and gas spread throughout the atmosphere.

Eventually, the Earth is wrapped in a layer of ash and gas.

Ash and gas plume from Mt. Etna, in northeastern Sicily.

Volcanic Contribution to Climate Change

Step 3

Ash and gas block energy from the Sun.

Earth's temperature drops.

Volcanic Contribution to Climate Change

Step 4

Heat radiating off the surface of Earth becomes trapped in the layer formed by the eruption.

Trapped heat changes global climate patterns.

Krakatau Sunsets 1883-85

Krakatau 1883 El Chichon 1982