Transcript Dark_Skies_2

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
Image A
Image B
Pristine Atmosphere
Layer of fine droplets
following the Pinatubo
eruption
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