Global Warming, what is it?

GLOBAL WARMING CAN BE FRAMED AS HUMANS VS. FORCES OF NATURE
1. the most talked about problems:
 Increasing drought
 Rising sea level
 Pole ward movement of tropical diseases
 Increasing frequency of extreme weather
2. The majority of scientists view the evidence as telling us that global
warming is real and the effect is accelerating.


EVIDENCE - ICE
In the last 100 years global average temperature has risen 1
o
F – a huge
amount for a global average.
In the arctic and antarctic the temperature rise is greater (as climate
models predict) and in the past 50 years amounts to 4
o
 to 7
o
F.
Arctic – Arctic Ocean sea ice is
 Forming later  Melting earlier
 Covers less area and
 Is thinner
Antarctic - Ice Shelves are disintegrating
 Jan to Mar 2002 – Larsen Ice Shelf, a floating slab of ice the size of
Rhode Island disintegrated. See images below and check out the links:
http://earthobservatory.nasa.gov/Study/LarsenIceShelf/
http://web.pdx.edu/~chulbe/science/Larsen/larsen2002.html
In Africa Mt. Kilimanjaro will soon be ice free and glaciers in the Swiss Alps
are retreating rapidly. EVIDENCE – ATMOSPHERIC CIRCULATION
The major circulation systems of Earth are migrating and as a result
climates are changing and may be destabilizing threatening to change
agricultural productivity.
Drought prone areas like the Great Plains of the U.S. will become drier
(warmer weather means more evaporation)
Flood prone areas will get more precipitation
(the evaporated water has to go somewhere and it will be released by more
intense lift in areas where it rains)
Evidence indicates that this is happening now.


A WAY TO LOOK AT GLOBAL WARMING IS:
Ancient sunlight vs. current sunlight – ancient sunlight refers to energy
stored in fossil fuels (thus ancient sunlight) in the form of hydrocarbons.
When used these fuels release carbon to the environment and increase CO2
in the system.
Increased CO2 will affect:
 Photosynthesis
 Blood chemistry
 Ocean acidity and of course the
 Greenhouse effect
 Soil chemistry – nitrogen from fossil fuels fertilizes soil micro
organisms which then emit even more CO2



THE BIGGEST PLAYERS IN THE IMMEDIATE FUTURE:
China and India with:
 Large populations and
 An increasing standard of living
 = INCREASED GREENHOUSE EMISSIONS Increasing World Population:
 As many as 9.3 billion people by 2050


EVIDENCE – HEALTH EFFECTS
The CO2 fertilization to date has lead to an increase of 9% in plant growth
and a 61% increase in pollen production->allergy increase.
Henta virus and West Nile virus (spread by mosquitoes).
Insect infestations will increase – bark beetles in Alaska – not in the film.



THE INVESTIGATION
Sea temperatures are warming and that means:
1. more energy for hurricanes
2. more heat to melt ice leading to
a. more fresh water in the polar oceans – decrease of the
circulation of the conveyor belt – may have been a factor in
the Little Ice Age.
b. less albedo from less ice – positive feedback
c. increasing sea level
3. water will expand and sea level will rise from this too
4. Less dissolved CO2 in the warmer water so even more in the
atmosphere.
El Niño frequency may increase]
Barrier islands may disappear (they already have in many areas south
of New Orleans even pre-Katrina).
The situation
1. Climate will be more variable = less reliable harvests
2. Food need will be greater = more hunger 3. Civilization may be destabilized = remember the Little Ice Age and
the French Revolution.


THE NEXT STEPS: HOW DO WE CLEAN UP OUR ACT?
More reliance on current sunshine – solar energy alternatives - in one
day the sun sends the equivalent of 27 years of energy for all Earth
uses. In some areas you can sell power back to the energy company.
Clean coal – less particulate by still a great deal of CO2
Wind power – wind farms
Bio-diesel
Hybrid technology (then hydrogen fuel cells)
Use of landfill methane
Energy efficient homes
Agriculture = hybrid crops that create more biomass and thus remove
carbon from the system.
Pump CO2 into the ground.
OLD WAY OF THINKING = CONSERVATION AND NEW
TECHNOLOGY THREATENS JOBS.
NEW WAY OF THINKING – NEW TECHNOLOGY CREATES JOBS