Global Environmental Issues:
Global Warming & Biodiversity Conservation
Causes
of Global Warming
¤ Earth has a natural greenhouse
effect – the trapping of incoming and outgoing solar radiation by
moisture and natural greenhouse gases
¤ Last 130 years: Industrial
Revolution
Has changed the amount of these natural greenhouse gases
1. Carbon Dioxide – from the burning of coal,
petroleum, gasoline
1860: 280 parts per million
2000: 370 parts per million
2010: 380+
2050:
400-600 parts per million (estimated)
CO2 emissions components
2. Chlorofluorocarbons (CFCs) – from aerosol sprays,
refrigeration, air conditioning
Increasing at a rate of 4% per
year
Absorbs a thousand times more
infrared radiation from Earth than a
molecule of carbon dioxide
3. Methane
– from vegetation burning (rainforest clearing), leakage of pipelines and
refineries associated with natural gas production, and ÔnaturalÕ leakage from
cattle and sheep
The atmospheric concentration of methane has
increased by 151% since 1750 and is its highest in 420,000 years.
4. Nitrous Oxide – from use of chemical fertilizers
5%
of human-caused greenhouse gases
5. Water Vapor – largest greenhouse gas and naturally
occurring
generally considered to increase with increased temperatures
Unanswered questions:
can water vapor lead to a feedback effect causing a
'runaway' greenhouse effect?
can areas become more arid? allowing greater reflectance
back into space?
how will it vary across regions? some hotter, more humid,
wetter...others more arid, dryer?
¤ About three quarters
of our greenhouse emissions are from burning fossil fuels and most of the rest
is from deforestation.
¤
1.
How will greenhouse emissions alter over time?
2.
What will happen to natural sinks?
i.
Soil? huge reservoirs
of CO2 are held in surface deposits such as soils, peats, etc.
What is the Present Effect of this Buildup of Greenhouse
Gases?
Iconic ImagesÉ
1. Keeling Curve
a.
Totals: increase in overall atmospheric content
b.Annual amplitude (a
bit hard to see on this graph): ÔgreeningÕ of North America and Siberia with
Global Warming
2.
CO2 and Temperature Change from Ice Cores
Big
difference between CO2 and temperature today. Far greater than at any time in
the last 300,000 years. Temperatures have not shown the same correlation thus
far, however. We hope they will not I supposeÉ
3.
Anthropogenic versus ÔnaturalÕ forcings
4.
Slide: Future scenarios
Slides: Sources and Sinks
What are Potential Effects of this Buildup of Greenhouse
Gases on Biodiversity?
Some ImpactsÉ Habitat Destruction
1.
Changes in Temperature affect glaciers and oceans
a.
Increase in Sea Level due to Thermal Expansion of the Ocean and
Melting of Ice Sheets:
Continental (Greenland, Antarctica), Mountain (Rockies, Kilimanjaro, Andean)
Millions of species will be displaced.
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Southeast Asia |
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Southeast Asia |
a. Loss of Ice Sheets and
associated ecosystems
i. Polar Bears,
ii. Vast under-ice ecosystem of
Krill and the related ecosystem
(sea lions, penguins)
iii. Mountain Ecosystems: many
pockets of biodiversity are dependent upon snowmelt.
5. Global Warming alters
terrestrial Ecosystems
a. Change in Animal / Plant Cycles
Earlier Migration and Breeding of Birds, Animals, and Plants
Change in CO2 concentrations may increase crop yields
Change in weather patterns may harm crop yields
Loss of fish populations in part due to global warming and
ocean acidification (see below)
6. Extra CO2 has effects as well
a. Acidification of the Ocean and Coral
Bleaching (Die-Offs):
warming AND difficulty of building shells of calcium
Coral Reef bleaching: loss of
related fish populations (added to direct destruction)
Basically:
Massive Ecological Changes with Massive Impacts on Society
Slides: Social Aspects of Greenhouse Gas
Production
The Politics of Global Warming
The
Problem of Assigning Responsibility
a.
Who is Responsible for Global Warming in the first place?
b.
Who should be Responsible for 'Cleaning Up the Mess'?
¤ 1992 Rio de Janiero
Earth Summit
Those who signed – bound by international
law to reduce their greenhouse gas emissionsÉbut those countries emitting the
most greenhouse gases
did not come closeÉ
¤ 1997 Kyoto, Japan
-Again, another
treaty aimed at cutting emissions.
-But the details as
to how this would happen were not decided onÉ
-A deal was finally
hammered out in Marrakech in 2001, although the United States, the #1 producer of greenhouse gases, pulled
out in 2000
Why did it take so long forÉ
countries to start talking and an agreement be
reached?
1. Debate over Global Warming in the US
¤ Some see a need to
control emissions
¤ Others worry
controls will
a. harm business
b. increase the cost
of living for Americans
2. In Contrast to the European Union
¤ More energy
efficient than the US and can meet the requirements with greater ease.
Nonetheless, many debates with respect to how to meet the challenges of global
warming:
i.
Nuclear power generation versus Renewables and Conservation
ii.20% reduction in
Germany versus increases in Portugal, Greece, Spain
3. Tensions between Industrialized and
Industrializing Nations
¤ Industrialized World
(the ÔWestÕ), created the global warming problem and today contributes more
than half of greenhouse gases.
¤ Therefore, some feel
industrialized nations shouldÉ
a. Drastically curb
their emissions
b. Finance emission
controls in developing countries
¤ Industrializing
countries are Reluctant to Sign becauseÉ
a. Emission controls will restrict their
economic future
Example:
ChinaÕs huge supply of soft coal – wants to use this coal to fuel
industrialization
b. They feel the responsibility does not lie
with them
Economic Argument
from Vandana Shiva:
director
of the Research Foundation for Science and Ecology, India
She opens with Two
General Statements:
1. Òthe threat to the atmospheric commons has been building over
centuries, mainly because of industrial activity in the NorthÉ[yet] the North
refuses to assume extra responsibility for cleaning up the atmosphere. No
wonder the Third World cries foul when it is asked to share the costs.Ó
2. The Third World calls for an "ecological democracy" -
the worst polluters should pay the highest price for cleaning the environment
Her Main Argument:
The North is not only Responsible for PollutingÉ The North is the
driving force behind industrialization in the Third World
¤ Western 'experts'
and organizations (ex - World Bank) have pushed the Third World into using oil,
gas, and 'modern' agriculture (herbicides, pesticides, fertilizer, etc.)
How has the North done this?
¤ Through regulations
and funding
Examples:
¤ World Bank's
"barometer of 'development'" = Energy Consumption
¤ Economies based on
Renewable Sources of Energy were assumed to be Unproductive
"ÔMost
agriculture is unproductive; human or animal manure may be used, but chemical
fertilizers and pesticides are unknown.Õ"
¤ The World Bank does
not want to fund governments that are "unproductive."
¤ If Third World
governments switched to an agriculture based on fossil fuels (tractors,
insecticides, fertilizers), they would continue to receive aid
¤ World Bank funds
power projects in the Third World
The National Thermal Power Corporation (coal based power plants) =
the largest beneficiary of World Bank assistance
¤ Also: Corruption in
Third World governments
What else is involved in this Push towards Fossil Fuels?
¤ Aid for fertilizer,
tractors, etc: benefits Western corporations.
"For every dollar of aid given, three dollars worth of
business is generated in the industrialized countries."
The Core Problem
¤ Debt Burden: prevents
the Third World from spending on the environment
¤ Undemocratic
regimes: Wealthy rulers profit from environmental degradation
Conclusion:
"If the North is really serious about coming to grips with
global warming - whether caused by higher levels of fossil-fuel use or faster
rates of deforestation - then debt and unequal trade must be tackled first.
Both are reflections of the deep rift between rich and poor which frustrates
our search for environmentally sustainable development."
Global Warming: A
complex environmental, social, and economic issue that ties the world togetherÉ
