Transcript The reflection of sunlight by volcanic dust might cause decrease in

What is a volcano?
Volcanoes are formed when magma from
within the Earth's upper mantle works its
way to the surface. At the surface, it erupts
to form lava flows and ash deposits.
VOLCANOES
http://youtu.be/wu1v1cgS9oU
RING_OF_FIRE - a zone of frequent earthquakes and volcanic eruptions that
encircles the basin of the Pacific Ocean.
Mid-ocean ridge volcano
Rifting,
Diverging
Boundary,
Sea-floor
spreading
Surface Volcanoes
• Cinder cone –
What’s it made of?
Shield volcanoes-basaltic
Composite Volcano
Composite volcanoes in North America
• Mt. Rainier
• Mt. Baker
Mt. St. Helen’s before
Mt. St. Helen’s after
A pyroclastic density current
is a fast-moving current of
hot gas and rock, which
reaches speeds moving away
from a volcano of up to 450
mph. The gas can reach
temperatures of about 1,000
°C (1,830 °F).
This heat can melt
the snow that has
accumulated at the
top of the volcano
and create a lahar.
If dust particles, ash and/or other aerosols are added to
the atmosphere atmospheric transparency decreases
and insolation may be blocked.
(bye bye dinos, hello Frankenstein)
Precipitation may
help to clear the
atmosphere.
How?
When Mount Pinatubo in the Philippines erupted in 1991, it
emitted millions of tonnes of SO2 that cooled the Earth
slightly for the next few years.
This might be a good resource for your project foreither side!!!!
http://www.climatecentral.org/news/volcanoes-may-mask-lost-warming-15683
http://www.fs.fed.us/gpnf/volcanocams/msh/
These lethal
mixtures of
water and ash
have the
consistency of
wet concrete.
HOT SPOTS
http://www.wwnorton.com/college/geo/egeo2/content/animations/2_6.htm
Caldera Volcano
http://www.ouramazingplanet.com//405yellowstone-national-park-old-faithfulsuper-volcano.html
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The reflection of sunlight by volcanic dust might cause decrease in
temperature.
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The Great Rift Valley
Rifting of Earth's crust in eastern Africa began
during the Neogene Period as the Ethiopian and
Kenyan Domes formed. These two huge domes
were created as Earth's mantle pushed up the
overlying crust. As the crust was forced upward,
the resulting tension cracked the crust, resulting in
the eruption of volcanoes and the formation of
large rifts. The crust continued to pull apart,
forming rift valleys. These valleys have become
deeper and are currently becoming filled with
sediments, igneous rock, and water. Rift valleys can
emit carbon dioxide and methane into the
atmosphere.
How can this type of volcano cause global
surface air temperatures to increase?
They emit carbon dioxide and methane which are
greenhouse gases. Greenhouse gases trap infrared
rays in our atmosphere causing temperatures to
rise.
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Based on the age pattern of the calderas shown on the
map, in which compass direction has the North
American Plate moved during the last 16 million years?
WSW or SW
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Based on the age of the bedrock of the Galapagos Islands, in
which direction does the tectonic plate containing the islands
appear to be moving away from the Galapagos Hot Spot?
Southeast or south