Transcript Global Change - Liberty Union High School District

Chapter 19 - Global Change
Global Change
• Global change- any chemical, biological or physical
property change of the planet. Examples include cold
temperatures causing ice ages.
• Global climate change- changes in the climate of the
Earth.
• “Global warming” - one aspect of climate change, the
warming of the oceans, land masses and atmosphere of
the Earth.
The Greenhouse Effect
• When radiation from the sun hits the
atmosphere, 1/3 is reflected back.
• Some of the UV radiation is absorbed by the
ozone layer and strikes the Earth where it is
converted into low-energy infrared radiation.
• The infrared radiation then goes back toward
the atmosphere where it is “trapped” or
absorbed by greenhouse gasses that radiate
most of it back to the Earth.
Greenhouse Gases
• Water vapor
• Carbon dioxide
• Methane
• Nitrous oxide
• Ozone
Natural Greenhouse Gases
• Volcanic eruptions- mainly carbon dioxide
• Methane – from decomposition
• Nitrous oxide- from denitrification
• Water vapor
Anthropogenic Causes of
Greenhouse Gases
• Burning of fossil fuels
• Agricultural practices
• Deforestation
• Landfills (decomposition)
• Industrial production (e.g. CFC’s)
The Greenhouse Effect
CO
Concentrations
2
• David Keeling began measuring CO in 1958.
Increasing
2
Emissions from the Developed
vs Developing World
Global Temperatures
• Since 1880 temperatures have increased 0.8°C.
since 1880
Temperatures and Greenhouse Gas
Concentrations in Past 400,000 Years
• No one was around thousands of years ago to measure
temperatures so we use other indirect measurements.
Some of these are
• Changes in species compositions
• Chemical analyses of ice cores
Temperatures and Greenhouse Gas
Concentrations in Past 400,000 Years
Putting It Together
• We know that an increase in CO2, methane and
other GHGs in the atmosphere causes a greater
capacity for warming through the greenhouse
effect.
• When the Earth experiences higher
temperatures, the oceans warm and cannot
contain as much gas and, as a result, they
release more CO2 and methane into the
atmosphere.
• (ie. “positive feedback loop”)
Feedbacks
Rising Seas
Consequences to the Environment
Because of Global Warming
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Melting of polar ice caps, Greenland and Antarctica
Melting of many glaciers around the world
Melting of permafrost
Rising of sea levels due to the melting of glaciers and
ice sheets and as water warms it expands
Heat waves
Cold spells
Change in precipitation patterns
Increase in storm intensity
Shift in ocean currents
Consequences to
Living Organisms
• Wild plants and animals can be affected.
• The growing season for plants has changed and animals
have the potential to be harmed if they can’t move to
better climates. – affecting seasons for migration
• Humans may have to relocate  “Climate Refugees”
• Some diseases like those carried by mosquitoes are
increasing
• Plus many economic consequences.
• Healthcare / Medical Insurance
• Agriculture – loss of food supply
• Structural Damage - Corrosion
The Controversy of
Climate Change
• The fundamental basis of climate change- that
greenhouse gas concentrations are increasing and that
this will lead to global warming is not in dispute among
the vast majority of scientists.
• What is unclear is how much world temperatures will
increase for a given change in greenhouse gases,
because that depends on the different feedback loops.
The Kyoto Protocol
• In 1997, representatives of the nations of the world went
to Kyoto, Japan to discuss how best to control the
emissions contributing to global warming.
• The agreement was that emissions of greenhouse gases
from all industrialized countries will be reduced to 5.2%
below their 1990 levels by 2012.
• Developing nations did not have emission limits imposed
by the protocol.
Other Global Agreements
COP1 Berlin 1995
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The first Conference of the Parties was marked by uncertainty as to which means the individual
countries possessed to combat greenhouse gas emissions. This resulted in “The Berlin Mandate”,
which set a two-year analysis and evaluation phase. This phase was to result in a catalogue of
instruments from which the member countries could choose and thereby compose a set of
initiatives that matched their needs.
COP2 Geneva 1996
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The second Conference of the Parties endorsed the results of the IPCC’s second assessment
report, which came out in 1995. At this conference it was established that member countries
would not pursue uniform solutions. Each country should have the freedom to find the solutions
that were most relevant to its own situation. At the Geneva conference the parties also
expressed a wish for binding targets to be defined in the medium-term future.
COP3 Kyoto 1997
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At this conference the Kyoto Protocol was adopted after intense negotiations. For the first time
the protocol introduced binding targets for greenhouse gas emissions in 37 industrialised
countries from 2008 to 2012. Subsequently there were several years of uncertainty as to whether
a sufficient number of countries would ratify the treaty, but on 16 February 2005 it came into
force. Several of the member countries of the UNFCCC have not ratified the Kyoto Protocol and
do not acknowledge its requirements regarding emissions.
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COP4 Buenos Aires 1998
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At this conference it became clear that there were several outstanding questions regarding the
Kyoto Protocol. A two-year period was therefore scheduled to clarify and develop tools for
implementing the Kyoto Protocol.
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COP5 Bonn 1999
Other Global Agreements
COP4 Buenos Aires 1998
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At this conference it became clear that there were several outstanding questions regarding the
Kyoto Protocol. A two-year period was therefore scheduled to clarify and develop tools for
implementing the Kyoto Protocol.
COP5 Bonn 1999
COP6 The Hague 2000
COP6 bis Bonn 2001
COP7 Marrakesh 2001
COP8 Delhi 2002
COP9 Milan 2003
COP10 Buenos Aires 2004
COP11/CMP1 Montreal 2005
COP12/CMP2 Nairobi 2006
COP13/CMP3 Bali 2007
COP14/CMP4 Poznan 2008
Carbon Sequestration
 An approach involving taking CO2 out of the
atmosphere.
 Some methods include storing carbon in agricultural
soils or retiring agricultural land and allowing it to
become pasture or forest.
 Researchers are looking at cost-effective ways of
capturing CO2 from the air, from coal-burning power
stations, and from other emission sources.
 This captured CO2 would be compressed and pumped
into abandoned oil wells or the deep ocean.
Carbon Credits
• a permit that allows a country or industrial
company to produce a certain amount of
carbon emissions and that can be traded if the
full allowance is not used.
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