OUR CHANGING ATMOSPHERE

1
OUR CHANGING ATMOSPHERE

• CHAPTER 5
• (cont.)

2
GLOBAL WARMING AND CLIMATE CHANGE

• Consensus but not unanimity
• Some argue that modest increases in global
  temperature were occurring before significant
  increases in CO2.
• Castles and Henderson suggest that IPCC
  predictions are based on flawed economic
  assumptions, using GDP rather than purchasing
  power parity

3
GLOBAL WARMING AND CLIMATE CHANGE

• Some are arguing that the Antarctic Ice Sheet are
  expanding rather that retreating.
• Another study found air temperatures in
  Antarctics polar desert actually declined by
  0.4oC from 1986-1999.
• Yet another study by Winsor indicates that threre
  is a slight increase in mean ice thickness at the
  North Pole.
• Morner points out that observed rises in sea
  level are less than predicted by the IPCC.

4
SCIENCE AT WORK

• At least some of these views are demonstration of
  scientific debate that occurs when theories are
  developed, working toward conclusive proof.
• However the consensus as expressed by the IPCC
  and thousands of other scientists Despite
  increasing consensus on the science underpinning
  predictions of global climate change, doubts have
  been expressed recently about the need to
  mitigate the risks posed by global climate
  change. We do not consider such doubts justified.

5
OTHER ATMOSPHERIC EVENTS

• Oceanic events that influence weather and climate
• El Nino
• North Atlantic Oscillation
• Pacific Decadal Oscillation
• Antarctic Circumpolar Wave
• Tropical Atlantic Variability

6
EL NINO AND SOUTHERN OSCILLATION

• Occurs every 3 to 7 years
• Invasion of warm water from western Pacific to
  Eastern Pacific off Peru and Chile
• Changes sea surface temperature and causes air
  pressure changes with result in wind pattern
  changes.
• Causes fish mortality off South America
• Creates monsoons in some areas and droughts in
  others ( Pacific northwest will be wetter and
  Western Arctic would be drier).

7
ACIDIC PRECIPITATION

• Due largely to emissions of sulphur dioxide (SO2)
  and nitrogen oxides (NOx) that are converted to
  sulphuric acid and nitric acid in the atmosphere.
• Can result in precipitation that is as much as
  100 times more acidic (pH 3.6) than natural
  precipitation (pH 5.6)

8
SOURCES OF ACID RAIN

• More than 90 from human activities.
• Sulphur dioxide comes from smelting and refining
  of sulphur bearing ores and fossil fuels
  containing sulphur.
• Nitrogen oxides come from transportation,
  industrial processes, power generation,
  fertilizers and other sources.
• Acidic pollutants can be carried up to 1,000
  kilometres.

9
EFFECTS OF ACID DEPOSITION

• Increasing acidification of soils and lakes in
  Eastern Canada with consequences for Atlantic
  Salmon reproduction
• Leaching of metals into water bodies
• Deterioration of some tree species such as birch
  and sugar maple.
• Aggravation of respiratory ailments

10
LONG RANGE TRANSPORT OF AIR POLLUTANTS

• While LRTAP can occur anywhere on the planet, the
  High Arctic appears to be a sink for many
  organic contaminants.
• Polychlorinated biphenyls (PCBs), polycyclic
  aromatic hydrocarbons (PAHs), hexachlorobenzene
  (HCB), toxaphene and chlordane have been found in
  Arctic animals especially seals, narwhals and
  whales.

11
SHORT RANGE TRANSPORT OF AIR POLLUTANTS

• Local and regional contamination
• Smog formation
• Ground level ozone
• Benzene
• Particulates

12
RESPONSES TO ATMOSPHERIC CHANGES

• INTERNATIONAL ACTION
• UN Framework Convention on Climate Change
• Intergovernmental Panel on Climate Change
• Kyoto Protocol
• Vienna Convention on Protection of the Ozone
  Layer
• Montreal Protocol
• London and Copenhagen Amendments

13
MONTREAL PROTOCOL

• In 1997, Canada released an independent study of
  the benefits and costs of the Protocol.
• The question that was asked Did the benefits
  outweigh the costs?
• Avoidance of harmful impacts on human health,
  agriculture, fisheries and building
  materials. eg. 19 million avoided cases of
  non-melanoma skin cancer and 1.5 million cases of
  melanoma
• Other benefits estimated at 459 million.

14
REDUCTION OF ACID DEPOSITION

• Eastern Canada Acid Rain Program (1985) resulted
  in a 57 reduction of 1980 levels in 1994.
• Canada -United States Air Quality Agreement
  (1991)
• Joint Plan of Action on Transboundary Air
  Pollutants (1997)
• Canada Wide Acid Rain Strategy (2000)
• Ozone Annex of the Canada-U.S. Air Quality
  Agreement (2000)

15
CANADIAN PROGRAMS AND INITIATIVES

• Knowledge of the Environment for Youth (KEY)
  Foundation
• International Co-operative for Environmental
  Leadership (Nortel)
• Pembina Institute
• International Council for Local Environmental
  Initiatives (ICLEI)
• Climate Change Voluntary Challenge Registry
• FCM Cities for Climate Protection