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
