The greenhouse effect occurs when an earth warmed by the solar spectrum radiates invisible infrared light back, but, instead of going back to space, it is partly absorbed by greenhouse gases in the atmosphere, making the atmosphere warmer. Substantial areas of North America are likely to have more frequent droughts of greater severity. Hurricane wind speeds, rainfall intensity, and storm surge levels are likely to increase. The strongest winter storms are likely to become more frequent, with stronger winds and more extreme wave heights. Presentation courtesy of Dr. Walter Hays, Global Alliance for Disaster Reduction
6. PRESENT UNDERSTANDING OF
ENVIRONMENTAL EXTREMES
• During 2007-2008, the
world began to
consider seriously the
environmental impacts
of global climate
change and the
possibility of
exacerbated impacts
from floods,
landslides, droughts,
and wildfires.
• Warmer air and warmer
water are a Rx for
enhancing severe
windstorms.
• Warmer air can hold more
water and unleash more
energy, making wind fields
stronger, storm surges
higher, rainfall heavier, and
floods and landslides more
frequent.
7. PRESENT UNDERSTANDING OF
ENVIRONMENTAL EXTREMES
• Earthquakes,
tsunamis, and
volcanoes have
tectonic ori-
gins, but some
of their physical
effects can be
exacerbated by
global climate
change.
Warmer air and
warmer water
may explain the
increase of
flooding in
Europe Asia,
South America,
and the USA
during 2007 and
2008..
8. PRESENT UNDERSTANDING OF
THE JET STREAM AND FLOODING
• A number of
flooding
disasters
occurred almost
simultaneously
around the
World in 2007
and 2008.
• Experts now know
that certain
configurations of
the jet stream can
produce flooding
nearly simultane-
ously in different
parts of the
World..
10. 1. THE AVERAGE GLOBAL
TEMPERATURE HAS INCREASED
BY 1.73 DEGREES F DURING
THE PAST 100 YEARS TO 57.9
DEGREES F
2. THE NORTHERN HEMISPHERE IS
WARMING FASTER THAN THE
SOUTHERN HEMISPHERE
11. 3. SATELLITE MEASURE-
MENTS INDICATE THAT THE
TROPOSPHERE IS
WARMING FASTER THAN
THE EARTH’S SURFACE.
NOTE: THIS IS CONSISTENT
WITH THE PHYSICS OF
GREENHOUSE GASES
ABSORBING HEAT.
12. 4. THE EARTH’S OCEANS
ABSORB 20 TIMES AS MUCH
HEAT AS THE EARTH’S
ATMOSPHERE.
5. THE PH LEVEL OF THE EARTH’S
OCEANS HAS INCREASED.
NOTE: THIS INDICATES AN
INCREASED ABSORPTION OF
CARBON DIOXIDE.
13. 6. AVERAGE GLOBAL SEA LEVEL
HAS INCREASED BY 4.7 INCHES
SINCE THE LAST ICE AGE.
7. SEA LEVEL RISES FOR TWO
REASONS: A) WATER EXPANDS
WHEN IT IS WARMER, AND B)
WATER VOLUME INCREASES
FROM MELT WATER.
14. 8. IF THE FLOATING ARCTIC ICE
CAPS MELT, GLOBAL SEA
LEVEL WILL NOT BE AFFECTED.
9. IF ALL THE SNOW AND ICE IN
GREENLAND MELTED, GLOBAL
SEA LEVEL WILL RISE 24 FEET.
15. 10. THE ALBEDO (PERCENT
OF LIGHT REFLECTED)
FOR FRESH SNOW IS 80-90
PERCENT, BUT ONLY
50-60 PERCENT FOR
MELTING ICE.
16. 12. THE SUN PROVIDES AN
AVERAGE OF ABOUT 1370
WATTS OF POWER THROUGH
EM RADIATION TO EVERY
SQUARE METER OF SURFACE IT
STRIKES.
NOTE: THIS IS CALLED THE SOLAR
CONSTANT.
17. 13. THE SOLAR SPECTRUM
INCLUDES VISIBLE (ROYGBIV),
ULTRAVIOLET (A WAVE LENGTH
TOO SHORT TO SEE), AND
INFRARED LIGHT (A WAVE
LENGTH TOO LONG TO SEE).
18. 14. ABOUT 30 PERCENT OF
THE INCOMING SOLAR
SPECTRUM IS REFLECTED
BACK TO SPACE FROM
CLOUDS, SNOW, AND, TO A
LESSER DEGREE, BY OTHER
SURFACES.
19. 15. THE BALANCE (ABOUT 70
PERCENT) OF THE
INCOMING SOLAR
SPECTRUM IS ABSORBED
BY LAND, AIR, WATER, OR
ICE.
20. 16. THE GREENHOUSE EFFECT
OCCURS WHEN AN EARTH
WARMED BY THE SOLAR
SPECTRUM RADIATES INVISIBLE
INFRARED LIGHT BACK, BUT,
INSTEAD OF GOING BACK TO
SPACE, IT IS PARTLY ABSORBED BY
GREENHOUSE GASES IN THE
ATMOSPHERE, MAKING THE
ATMOSPHERE WARMER.
21. 17. THE GREENHOUSE EFFECT
OCCURS NATURALLY.
18. THE ISSUE IS: “HAVE HUMAN
ACTIVITIES ENHANCED THE
GREENHOUSE EFFECT BY
INCREASING GREENHOUSE
GASES ABOVE HISTORIC
LEVELS?”
22. 19. WITHOUT THE NATURAL
GREENHOUSE EFFECT, PLANET
EARTH WOULD BE AT A MUCH
COLDER TEMPERATURE; E.G.,
MINUS 2 DEGREES F.
20. WITH AN ENHANCED GREENHOUSE
EFFECT, PLANET EARTH WOULD BE
WARMER THAN THE AVERAGE
SURFACE TEMPERATURE OF 57.9
DEGREES IT NOW ENJOYS.
23. 21. CARBON DIOXIDE ENTERS THE
ATMOSPHERE NATURALLY.
22 NATURAL PHYSICAL
PROCESSES REMOVE CARBON
DIOXIDE FROM THE ATMO-
SPHERE.
24. 23. AS THE GREENHOUSE
EFFECT CAUSES HIGHER
TEMPERATURES IN THE
ATMOSPHERE, THE
REMOVAL RATE OF CARBON
DIOXIDE IS DECREASED.
25. •"Heat waves and
heavy downpours are
very likely to increase
in frequency and
intensity.”
26. • "Substantial areas of
North America are
likely to have more
frequent droughts of
greater severity.”