Download Volcanoes and the Earth System

Volcanoes and the Earth System
BAESI
November 17, 2007
NASA Earth Science for Teachers
On-line modules
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Science content
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Teaching strategies including hands-on
lessons
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Incorporation of NASA data, images and
other and materials
Earth System Science
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Earth is a dynamic body with
many separate, but highly
interacting parts or spheres.
Earth system science studies
Earth as a system composed
of numerous subsystems.
Earth’s Interacting Spheres
Cosmosphere
Source : Dr. Rick Behl
CSU Long Beach
Review
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Types of volcanoes
Volcanoes and plate boundaries
Igneous processes
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Volcanic
Intrusive
Controls on eruptive behavior
Products of volcanism
Volcanoes and the Earth System
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Volcanoes- geosphere
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Volcanoes-atmosphere
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Climate change
Natural pollution
Volcanoes-biosphere
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Creation of new land
Origin of life at hydrothermal vents?
Fertile soils
Impact of eruptions
Extinction
Volcanoes-hydrosphere
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Hydrothermal activity
Volcanoes and the Earth System
Volcanic
emissions
N2
remains
N2
CO2
photosynthesis
O2
H2O
condensation
oceans
99% of
atmosphere
Volcanoes produced the atmosphere and the
oceans
Alan Robock, Rutgers
Volcanoes: Pros and Cons
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What are some benefits?
What are some hazards?
Volcanoes: Pros and Cons
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What are some benefits?
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Soils
Geothermal energy
Scenery
What are some hazards?
Volcanoes and climate change
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Ben Franklin – Laki
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Iceland: Laki erupted in 1783
Eastern U.S: lowest-ever
winter average temperature in
1783-84,
Europe also experienced
severe winter.
Benjamin Franklin: cold
conditions resulted from the
blocking out of sunlight by
dust and gases created by the
eruption in 1783.
Source: How Volcanoes Work: http://www.geology.sdsu.edu/how_volcanoes_work/
Volcanoes and climate change
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Eruptions emit dust particles and gases
May cause warming or cooling, depending on how solar
radiation interacts with the material
Ash in lower atmosphere (troposphere) are quickly washed
out of air
Dust that reaches the upper atmosphere (stratosphere) can
remain suspended and may cause global cooling for months
or years after the eruption
Volcanoes that erupt large quantities of sulfur compounds
have the greatest effect
Source Exploring the Environment Volcanoes Module: http://www.cotf.edu/ete/modules/
SO2  H2SO4 sulfuric acid (aerosols)
http://vulcan.wr.usgs.gov/Projects/Emissions/vgas_fsheet.pdf
Santorini, 1628 B.C.
Responsible for the legends of:
Atlantis (Minoans on Crete)
Biblical plagues
Parting of the Red Sea
Alan Robock, Rutgers University
Tambora in 1815, together with an eruption from an unknown
volcano in 1809, produced the “Year Without a Summer” (1816)
Global Surface Temperature Reconstruction
0.3
Anomaly (°C)
0.2
0.1
0
-0.1
-0.2
-0.3
Year
Mann et al. (2000)
Alan Robock, Rutgers University
1980
1960
1940
1920
1900
1880
1860
1840
1820
1800
1780
1760
1740
1720
1700
-0.4
Tambora, 1815, produced the
“Year Without a Summer” (1816)
Mary Shelley
George Gordon,
Lord Byron
Summer of 1816: Percy Bysshe Shelley, his wife Mary Wollstonecraft Shelley, and
Lord Byron went to Lake Genevafor their summer holiday
Alan Robock, Rutgers University
Tambora, 1815, produced the “Year Without a
Summer” (1816)
“Darkness”
by Byron
I had a dream, which was not all a dream.
The bright sun was extinguish'd, and the stars
Did wander darkling in the eternal space,
Rayless, and pathless, and the icy earth
Swung blind and blackening in the moonless air;
Morn came and went—and came, and brought no day,
And men forgot their passions in the dread
Of this their desolation; and all hearts
Were chill'd into a selfish prayer for light:
And they did live by watchfires—and the thrones,
The palaces of crowned kings—the huts,
The habitations of all things which dwell,
Were burnt for beacons; cities were consumed,
And men were gather'd round their blazing homes
To look once more into each other's face; . . .
Alan Robock, Rutgers University
Krakatau, 1883
The Loudest Explosion Ever Heard
Alan Robock, Rutgers University
Krakatau, 1883
Watercolor by William Ascroft
Figure from Symons (1888)
Alan Robock, Rutgers University
“The Scream”
Edvard Munch
Painted in 1893 based
on Munch’s memory of
the brilliant sunsets
following the 1883
Krakatau eruption.
Alan Robock, Rutgers University
Volcanoes and Mass Extinction
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Flood basalts (“traps”): huge outpourings of lava
Environmental effects:
 climatic cooling from sulfuric acid aerosols
 greenhouse warming from CO2 and SO2 gases
 acid rain.
http://www.geolsoc.org.uk/gsl/education/flood_basalts_1;jsessionid=9F8C28EDDD70A08C582D5C2AB0F50FEA
http://faculty.plattsburgh.edu/thomas.wolosz/floodextinct.jpg
What killed the dinosaurs?
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Asteroid?
Volcanism (Deccan traps – India)
Both asteroid impact and volcanism?
Supervolcanoes
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“Supervolcano” : An eruption of more than 1,000 cubic kilometers (240
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cubic miles) of magma.
Most recent: 74,000 years ago at the Toba Caldera in Sumatra, Indonesia.