Climate Paper Slideshow

1. Climatic Effects of the Eruption
of Mount Pinatubo
Climate Dynamics
Tyler Lawson
October 26, 2012

2. Mount Pinatubo

3. Massive Eruption of Pinatubo
• Took place on June 15
• Produced an ash cloud 34 kilometers high
• Produced the largest stratospheric aerosol
cloud of the 20th century
• 20 Megatons of sulfur dioxide and 10 cubic
kilometers of earth thrown into the sky
• Rate a 6 on the 0-8 Volcanic Explosive Index

4. Climatic Effects
• Stratospheric temperature changes
• Surface temperature changes
• Ozone depletion

5. Stratospheric Temperature Changes
• Stratospheric temperature rose due to the
absorption of incoming short wave solar
radiation
• This absorption was due to the aerosolized
sulfur dioxide cloud produced by the eruption
• After a few years when the sulfur dioxide left
the stratosphere in the form of acid rain the
stratosphere cooled to a temperature below
the mean

6. Surface Temperature Changes
• The same aerosolized cloud that increased
stratospheric temperature also lowered surface
temperature by blocking incoming shortwave
solar radiation, but allowing longwave heat
radiated from the Earth to escape into space
• This changed the albedo of the Earth and it
produced a cooling effect of 0.5 degrees C over a
two year period
• As the cloud dissipated the radiation balance
returned to normal and the temporary cooling of
the surface ended

7. Surface Temperature Northern
Hemisphere
Northern Hemisphere Surface Temperature
1.4
1.2
JAN
1
FEB
0.8 MAR
Degrees C from Mean
APR
0.6
MAY
0.4 JUN
JUL
0.2
AUG
0 SEP
1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 OCT
-0.2
NOV
-0.4 DEC
-0.6
Year

8. Surface Temperature Change Southern
Hemisphere
Southern Hemisphere Surface Temperature
0.9
0.8
0.7 JAN
FEB
0.6
MAR
Degrees C from Mean
0.5 APR
MAY
0.4
JUN
0.3 JUL
0.2 AUG
SEP
0.1
OCT
0 NOV
1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 DEC
-0.1
-0.2
Year

9. Ozone Depletion
• The aerosolized sulfur dioxide in the
stratosphere permitted increased chances for
chemical reactions that destroy ozone to take
place
• The sulfur dioxide allowed the chemical
reaction for the creation of chlorine to occur
and chlorine is a destroyer of ozone

10. Ozone Depletion
• Ozone depletion took place in the Northern
Hemisphere and not the Southern
• This is due to the fact that the eruption took
place during the warm phase of the El Nino
Southern Oscillation along with an enhanced
Brewer-Dobson circulation
• Atmospheric blocking also contributed to this
due to a pronounced negative phase in the
Southern Annual Mode

11. Conclusion
• Climatic effects of Mount Pinatubo eruption while
pronounced and measurable were temporary
• There were no affects on worldwide flora or fauna
except those affected locally by the eruption
• The data gained from studying the eruption allowed
scientists to test many climate circulation models and
confirm or refine them
• Mount Pinatubo eruption did show that volcanic
eruptions can directly effect climate and larger
eruptions would have a longer term, more pronounced
effect