Download - FUNDAMENTALS OF GLOBAL CLIMATE CHANGE
FUNDAMENTALS OF GLOBAL CLIMATE CHANGE
Physical CausesConsequencesPrevention, Mitigation, Monitoring, and Adaptation
FUNDAMENTALS OF GLOBAL CLIMATE CHANGE
Physical Causes
PLANET EARTH
PHYSICAL INTERACTIONS OCCUR ON MANY SCALES
• Propagation, reflection, and refraction of light and EM waves from the sun (creating the solar input)
• Absorption, storage, and re-radiation of light and EM waves (causing the “natural” greenhouse effect).
• Absorption of heat by greenhouse gases in the atmosphere (causing the “Unnatural” greenhouse effect).
WHAT DOES IT ALL MEAN?
• THE “NATURAL” GREENHOUSE EFFECT KEEPS THE EARTH WARM AT ABOUT 57.9 DEGREES F, AND
• THE “UNNATURAL”GREENHOUSE EFFECT CAUSES THE ATMOSPHERE’S TEMPERATURE TO RISE, FOLLOWED BY A RISE IN LAND AND OCEAN TEMPERATURES, CAUSING CLIMATE CHANGE ON A GLOBAL SCALE
THE GREENHOUSE EFFECT OCCURS WHEN AN EARTH WARMED BY THE SOLAR SPECTRUM RADIATES INVISIBLE INFRARED LIGHT BACK, BUT…
CONTINUED …INSTEAD OF GOING BACK
TO SPACE, IT IS PARTLY ABSORBED BY GREENHOUSE GASES IN THE ATMOSPHERE
NOTE: ABSORPTION MAKES THE ATMOSPHERE WARMER.
A WARMING EARTH: SEPT 25, 2007
THE AVERAGE GLOBAL TEMPERATURE HAS RISEN 1.7
DEGREES F IN PAST 150 YEARS
2005 - HOTTEST YEAR ON RECORD
• According to NASA and other organizations, 2005 was the hottest year on record for the Northern Hemisphere.
• Temperatures were about 1.4 degrees Fahrenheit above the historical average.
SATELLITE MEASUREMENTS INDICATE THAT THE TROPO-SPHERE IS WARMING FASTER THAN THE EARTH’S SURFACE.
NOTE: THIS INDICATES THAT GREENHOUSE GASES IN THE ATMOSPHERE ARE ABSORBING TOO MUCH HEAT.
SOLAR INPUT After hitting Earth's
upper atmosphere, about one - third of the sun's energy is reflected back into space.
The two-thirds that gets through the atmosphere drives Earth's weather engine
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.
THE SOLAR SPECTRUM INCLUDES: VISIBLE LIGHT (ROYGBI), ULTRAVIOLET LIGHT (A WAVE LENGTH TOO SHORT TO SEE), AND INFRARED LIGHT (A WAVE LENGTH TOO LONG TO SEE).
ABOUT 33 PERCENT OF THE INCOMING SOLAR SPECTRUM IS REFLECTED BACK TO SPACE FROM CLOUDS, SNOW, AND, TO A LESSER DEGREE, BY LAND SURFACES..
THE BALANCE (ABOUT 70 PERCENT) OF THE INCOMING SOLAR SPECTRUM IS ABSORBED BY LAND, AIR, WATER, OR ICE.
THE OCEANS STORE HEAT
Oceans, the source of moisture in the air, store heat more effectively over the long term than land and transports it efficiently over distances of thousands of miles.
• THE EARTH’S OCEANS ABSORB 20 TIMES AS MUCH HEAT AS THE EARTH’S ATMOSPHERE.
• THE pH LEVEL OF THE EARTH’S OCEANS HAS INCREASED.
NOTE: THE pH INCREASES AS CARBON DIOXIDE IS ABSORBED.
SEA LEVEL RISES FOR TWO REASONS:
WATER EXPANDS WHEN IT IS WARMED, AND
WATER VOLUME INCREASES AS MELT WATER IS ADDED.
AVERAGE GLOBAL SEA LEVEL HAS INCREASED BY 4.7 INCHES SINCE THE LAST ICE AGE.
• IF THE FLOATING ARCTIC ICE CAPS MELT, GLOBAL SEA LEVEL WILL NOT BE AFFECTED.
• IF ALL THE SNOW AND ICE IN GREENLAND MELTED, GLOBAL SEA LEVEL WILL RISE 24 FEET.
CLOUDS CAUSE BOTH COOLING AND WARMING
Clouds cool Earth by reflecting incoming solar energy.
Clouds cool Earth by slowing evaporation.
Clouds warm Earth by trapping heat being re-radiated upward from the Earth’s surface.
LAND SURFACES AFFECT TEMPERATURES AND MOISTURE
Mountain ranges can block clouds, creating "dry" shadows downwind.
Sloping land facilitates water runoff, leaving the land and air drier.
ICE AND SNOWIce and snow reflects
heat outward into space, cooling Planet Earth in the process.
When ice melts into the ocean, the ocean water losses some of its stored heat.
THE ALBEDO (PERCENT OF LIGHT REFLECTED) FOR FRESH SNOW IS 80-90 PERCENT,
BUT IT IS ONLY 50 – 60 PERCENT FOR MELTING ICE.
GREENHOUSE GASES IN THE ATMOSPHERE
“Greenhouse" gases include water vapor, carbon dioxide, methane and nitrous oxide.
WATER VAPORHigher air
temperatures increase the rate of water vaporization.
Water vapor is the most potent greenhouse gas.
VOLCANIC ERUPTIONS
Volcanic eruptions add water vapor and ash to the atmosphere.
“UNNATURAL”GREENHOUSE EFFECT
Greenhouse gases trap heat inside the atmosphere.
Too much trapped heat increases temperatures in the atmosphere and on the land and ocean surfaces, which causes climate change.
• THE GREENHOUSE EFFECT OCCURS NATURALLY.
• HUMAN ACTIVITIES EXACERBATE THE “UNNATURAL” GREENHOUSE EFFECT BY INCREASING CERTAIN GREENHOUSE GASES (E.G., CO2) ABOVE HISTORIC LEVELS.
• WITHOUT THE “NATURAL” GREENHOUSE EFFECT, PLANET EARTH WOULD BE MUCH COLDER; E.G., A TEMPER-ATURE OF ABOUT
MINUS 2 DEGREES F.
• WITH AN “UNNATURAL” GREENHOUSE EFFECT, PLANET EARTH WOULD BE WARMER THAN THE CURRENT AVERAGE TEMPERATURE OF 57.9 DEGREES F.
CARBON DIOXIDE ENTERS THE ATMOSPHERE NATURALLY, AND
NATURE REMOVES CARBON DIOXIDE FROM THE ATMOSPHERE NATURALLY.
THE OCEANS ARE A NATURAL CARBON SINK
The oceans and marine life remove and/or consume huge amounts of carbon dioxide.
• AS THE GREENHOUSE EFFECT INCREASES TEMPERATURES IN THE ATMOSPHERE, THE REMOVAL RATE OF CARBON DIOXIDE IS DECREASED.
HUMAN INFLUENCES
Humans are exacerbating warming by adding much more carbon dioxide to the greenhouse gases that are naturally present in the atmosphere, through ….
Extensive use of fossil fuels.
HUMAN INFLUENCES Aerosols, smoke and
sulfates reflect sunlight away from the Earth, which outweigh ----.
The temporary, localized cooling effects from aerosols and the smoke and sulfates from industry.
HUMAN INFLUENCES ON LAND SURFACES
Once tropical forests (a carbon sink) are cleared for cattle ranching or community development, the cleared land can becomes a major source of methane, a greenhouse gas.
FUNDAMENTALS OF GLOBAL CLIMATE CHANGE
Consequences
THE WATER CYCLE AND THE “UNNATURAL” GREENHOUSE EFFECT
Higher air temperatures increase the rate of water vaporization (Water vapor is the most potent greenhouse gas) and accelerate the melting of ice.
.
THE CONSEQUENCES OF GLOBAL CLIMATE CHANGE
• Worldwide rise in sea level.• Collapse of the Atlantic thermohaline
circulation (“The Atlantic Conveyor Belt”). • Increased probability of severe windstorms.• Larger storm surges in seasonal hurricanes
and typhoons.• Prolonged droughts in some regions and
heavy precipitation in others.
THE CONSEQUENCES OF GLOBAL CLIMATE CHANGE
• Reduced fresh water for a large portion of humankind that presently obtains its fresh water from glacier-fed rivers.
• Loss of function of activities such as winter ski resorts.
ATLANTIC THERMOHALINE CIRCULATION
• The Atlantic Conveyor Belt keeps Europe from becoming a deep freeze in the winter.
• Ancient sediments, ice cores, and fossils indicate that the Atlantic Conveyor Belt shifted abruptly about 8,200 years ago, when a sudden cooling occurred.
ATLANTIC CONVEYOR BELT• As a result, the land
temperature in Greenland dropped more than 9 degrees Fahrenheit within ONE OR TWO decades, an effect that could prove disastrous for Europe.
GREENLAND’S ICEBERGS
GREENLAND
• Greenland's glaciers are melting into the sea twice as fast as the previously calculated rate of four miles per year.
• This faster rate, if continued in concert with similar observations in the Himalayas and South America, makes predictions of how quickly Earth's oceans will rise over the next century questionable and probably obsolete.
GREENLAND AND ANTARCTICA
• The ice sheets in Greenland and Antarctica are among the largest reservoirs of fresh water on Earth.
• How much sea level will rise as a result of faster melting is unclear.
• Current estimates of around 50 cm (20 in) over the next century may be much too low.
DECREASING ICE THICKNESS AT QUELCAYA, PERU
GLACIAL RETREAT: COLOMBIA
GLACIAL RETREAT: BALAIS, SWITZERLAND
GLACIAL RETREAT: GLACIER NATIONAL PARK, MONTANA
SHEPHARD GLACIER: 1913 (LEFT) AND 2005 (RIGHT)
GRINNELL GLACIER: 1938 (LEFT) AND 1991 (RIGHT)
CORAL BLEACHING
• Ocean temperatures that are too warm stress corals, causing them to expel symbiotic micro-algae—their food supply-- which lives in their tissues.
• As a result, the reefs appear bleached. • Bleaching that lasts longer than a week
can kill corals.• One of the significant long-term impact is
on the fishing industry.
CORRAL BLEACHING FROM TEXAS TO TRINIDAD
FUNDAMENTALS OF GLOBAL CLIMATE CHANGE
Prevention, Mitigation, Monitoring, and Adaptation
THE TIPPING SCENARIO ISSUE OF GLOBAL CLIMATE CHANGE
• The “Tipping Scenario Issue” is:
• Within a few decades, will humans be virtually helpless to slow, much less, reverse the risks associated with global warming?
THE TECHNOLOGY ISSUE OF GLOBAL CLIMATE CHANGE
• “The Technology” issue is: “Can the global community slow and possibly reverse the perceived increasing adverse risks through timely technological innovations for prevention, mitigation, monitoring, and adaptation?”
BOOK OFBOOK OF
KNOWLEDGE
KNOWLEDGE
- Perspectives
- Perspectives
On Science, Policy,
On Science, Policy, And Change
And Change
LOCAL & LOCAL & REGIONAL REGIONAL
SCALESSCALESDATA BASES DATA BASES AND INFORMATIONAND INFORMATION
HAZARDS: GROUND SHAKING GROUND FAILURE SURFACE FAULTING TECTONIC DEFORMATION TSUNAMI RUN UP AFTERSHOCKS
•MEASUREMENTS• MAPS•INVENTORY•VULNERABILITY•LOCATION
RISK ASSESSMENTRISK ASSESSMENT
RISK
ACCEPTABLE RISK
UNACCEPTABLE RISK
ANTICIPATORY ANTICIPATORY DECISIONS DECISIONS
•PREVENTION/MITIGATION•MITIGATION•MONITORING•ADAPTATION
GLOBAL CLIMATE GLOBAL CLIMATE CHANGE CHANGE
Living with Global Climate ChangeLiving with Global Climate Change
INCREASED DEMANDS INCREASED DEMANDS ON COMMUNITYON COMMUNITY
NO DISASTERNO DISASTER : :
INCREASED INCREASED CAPABILITIES OF CAPABILITIES OF
COMMUNITYCOMMUNITY
Living With Global Climate ChangeLiving With Global Climate Change
INCREASED DEMANDS INCREASED DEMANDS ON COMMUNITYON COMMUNITY
A DISASTERA DISASTER : :
DECREASED DECREASED CAPABILITIES OF CAPABILITIES OF
COMMUNITYCOMMUNITY
Prevention, Mitigation and Adaptation Measures
• PREVENTION (CONTROL THE SOURCE)
• MITIGATION (REDUCE THE IMPACTS)
• ADAPTATION (ANTICIPATE)
Measures (continued)
• MONITORING • SCENARIOS• ADAPTATIVE
RESPONSE TO MONITORING AND SCENARIOS
ADAPTATION: THAMES RIVER, LONDON
•A report of the U.S. Climate Change Science Program, a joint effort of more than a dozen government agencies•The full report is online at www.usgcrp.gov•June 20, 2008
•"Heat waves and heavy downpours are very likely to increase in frequency and intensity.”
• "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 cold season storms are likely to become more frequent, with stronger winds and more extreme wave heights."
• Soil amplification of earthquake ground shaking is likely to be more pervasive.
• Landslides triggered in earthquakes are likely to be more extensive.
• The effects of tsunami wave run up will be more extensive.
“By the end of this century rainfall amounts expected to occur every 20 years now could be taking place every five years.”
y the end of this century rainfall amounts expected to occur every 20 years could be taking place every five years.•Such an increase "can lead to the type of events that we are seeing in the Midwest," said Karl, though he did not directly link the current flooding to climate change.
Such an increase "can lead to the type of severe floods that we are seeing at present in the Midwest.“ •
y the end of this century rainfall amounts expected to occur every 20 years could be taking place every five years.•Such an increase "can lead to the type of events that we are seeing in the Midwest," said Karl, though he did not directly link the current flooding to climate change.
•The heavy rains fell on a landscape that had been radically reengineered by humans for 50 years. •Plowed fields have replaced tall grass prairies.
•Former prairie grass fields were meticulously drained with underground pipes. •Streams and creeks were straightened.
• Most of the former wetlands were gone. • Community development had taken over former floodplains. w
• Comprehensive emergency management will be more difficult to plan and implement in the future.• Sustainable infrastructure will also be difficult to plan and achieve.