Geography 2153 Fall 2013 Environment, Economy and Society Our
Changing Atmosphere (Ch 5) Jamie Baxter 10/14/2013 20:05 Baxter
Geog 21531
Slide 2
Outline Atmospheric concerns Climate systems Changes,
atmospheric composition Greenhouse effect and climate change Ozone
layer Airborne contaminants Acidic deposition Policy responses
Challenges to air quality sustainability 10/14/2013 20:05 Baxter
Geog 21532 Fires to clear for palm oil plantation in Indonesia
engulf Singapore and Malaysia in particulate matter laden smog
Slide 3
Human Activities that Alter Earths Atmosphere 10/14/2013 20:05
Baxter Geog 21533 ActivitySubstances with Negative Atmospheric
Effect IndustrialSO 2, particulates (PM), CFCs heavy metals,
reactive hydrocarbons (HCs) Burning fossil fuelsGHGs, SO 2
TransportationGHGs, smog, NO x, So x, polycyclic aromatic HCs
(PAHs), carbon monoxide (CO) DeforestationGHGs, CO, PAHs, PM, loss
of carbon sinks Agricultural practicesCH 4
Natural Green House Gas Effect Natural and anthropogenic
process 0.6 average global surface air increase in temperature last
100 years Accelerating in recent decades (most likely) due to
anthropogenic causes Time lag - changes now may not have effects
for decades 10/14/2013 20:05 Baxter Geog 21535 Short wave radiation
in, long wave out. 90% long wave absorbed by clouds, vapour,
GHGs
Slide 6
Natural Green House Gas Effect GHGs are both natural and
anthropogenic: carbon dioxide (CO 2 ); methane (CH 4 ); nitrous
oxide (N 2 O); water vapour; ozone (0 3 ) What are some natural
sources (pre- industrialization) of these gases? 10/14/2013 20:05
Baxter Geog 21536
Slide 7
Enhanced Greenhouse Gas Effect Concentrations of: CO 2
increased 31 +/- 4% CH 4 increased 151 +/- 25% NO 2 increased 17
+/- 5% exceed any past levels detectable in fossilized air bubbles
of ice cores over the past 420,000 years unprecedented rate of
increase in last 20,000 years halocarbons: clearly human sources
10/14/2013 20:05 Baxter Geog 21537
Slide 8
Enhanced Greenhouse Gas Effect Characteristics of changes in
GHGs GWP Global Warming Potential the climate forcing potential of
greenhouse gases as CO 2 eq(uivalents) changes in
chlorofluorocarbons and halons: synthetic changes in aerosols:
small solid or liquid particles suspended in the air, contribute to
photochemical smog, acid deposition, etc. (volcanic eruptions,
aircraft emissions) 10/14/2013 20:05 Baxter Geog 21538 Greenhouse
GasFormula 100-year GWP (SAR) 100-year GWP (AR4) Carbon
dioxideCO211 MethaneCH42125 Nitrous oxideN2O310298 IPCC Fourth
Assessment Report (AR4) in 2007 refined IPCC Second Assessment
Report (SAR) values but the latter still in much of the
literature
Slide 9
Proposed Causes of Climate Change Changes in: solar intensity
stratospheric and tropospheric aerosol concentrations
concentrations of GHGs ozone layer thickness ocean - atmosphere
systems (e.g., El-Nio) 10/14/2013 20:05 Baxter Geog 21539 Which is
considered by the Intergovernmental Panel on Climate Change to
likely be the most important cause of accelerated climate change in
recent decades?
Slide 10
Enhanced Greenhouse Gas Effect Characteristics of changes in
GHGs changes in human-made chlorofluorocarbons and halons (both
derivative of methane) changes in aerosols: small solid or liquid
particles suspended in the air, contribute to photochemical smog,
acid deposition, etc. (e.g.,volcanic eruptions, aircraft emissions)
10/14/2013 20:05 Baxter Geog 215310 methane emitters aerosol + ghg
emitters
Slide 11
Enhanced Greenhouse Gas Effect 10/14/2013 20:05 Baxter Geog
215311
Slide 12
10/14/2013 20:05 Baxter Geog 215312
Slide 13
Impacts of Global Climate Change 10/14/2013 20:05 Baxter Geog
215313 drought and flooding glacial retreat leads to flooding,
erosion, and alters hydrological cycle
Slide 14
Thinning of the (Stratospheric) Ozone Layer Ground-level ozone
vs stratospheric ozone stratospheric: 15-40km, but maximum
concentration 20- 25 km above the Earths surface ozone hole, polar
vortex, polar stratospheric clouds 10/14/2013 20:05 Baxter Geog
215314
Slide 15
Thinning of the (Stratospheric) Ozone Layer Ozone (O 3 )
depleting substances (ODS) e.g., volcanoes, chlorofluorocarbons
(CFCs) Sunlight breaks Cl away from various forms of CFC then... Cl
+ O 3 ClO + O 2 ClO + O Cl + O 2 one Cl can destroy 100,000 0 3
10/14/2013 20:05 Baxter Geog 215315 Short video on ozone and
chlorofluorocarbons CFCs used to be common propellants in aerosol
cans (now petroleum products are used GHGs)
Slide 16
Thinning of the Ozone Layer Spatial variations in ozone
depletion Antarctic - severe polar vortex polar stratospheric
clouds Arctic less severe Tropical/Mid-Latitude least 10/14/2013
20:05 Baxter Geog 215316
Slide 17
Temporal Variation in Stratospheric Ozone 10/14/2013 20:05
Baxter Geog 215317
Slide 18
Climate Change and Ozone Depletion 10/14/2013 20:05 Baxter Geog
215318 Different policies address substances that contribute to
ozone depletion and climate change.
Slide 19
Effects of Ozone Depletion Increased ultraviolet (UV) radiation
decreased phytoplankton production (primary producers!) biological
damage human health threats Canadas UV Index Minimizing Risks of UV
Exposure Predictive model based on: sun altitude, ozone
concentration, ground altitude, the surface albedo, and cloud cover
(not actual radiation) 10/14/2013 20:05 Baxter Geog 215319 Long
wave penetrates more but short wave tends to do more damage protect
against both!
Slide 20
Ground-Level Ozone Human health risk Component of smog
Respiratory problems VOCs volatile organic compounds paints,
pesticides, gas vapour, glues, markers 10/14/2013 20:05 Baxter Geog
215320 The baking involves chemistry way beyond the scope of this
course, NOx can also combine with carbon monoxide (CO) to form O
3
Slide 21
Smog Mainly particulate matter and ground-level ozone along
with their precursors 10/14/2013 20:05 Baxter Geog 215321
Slide 22
Smog and PM 2.5 Penetrates deep into the lungs Impairs lung
function Sources (combustion): motor vehicles, power plants
(coal!), residential wood burning, forest fires, agricultural
burning, industrial processes 10/14/2013 20:05 Baxter Geog
215322
Slide 23
Responses to Atmospheric Changes National Canada-Wide Acid Rain
Strategy for Post 2000 Climate Change Action Fund Ozone Layer
protection program National Action Program on Climate Change Canada
Wide Standards for O 3 and PM 10/14/2013 20:05 Baxter Geog 215323
International Framework Convention on Climate Change Earth Summit
Kyoto Protocol (Canada withdrew in 2011 why?) Montreal Protocol
Canada-US Air Quality Agreement
Slide 24
Trends in Criteria Air Contaminants over Time Criteria air
contaminantsCriteria air contaminants: Sulphur Oxides (SO x );
Nitrogen Oxides (NO x ); Particulate Matter (PM); Volatile Organic
Compounds (VOC); Carbon Monoxide (CO); Ammonia (NH 3 ) Ground level
ozone (O 3 ) 10/14/2013 20:05 Baxter Geog 215324
Slide 25
Trends in Criteria Air Contaminants over Time 10/14/2013 20:05
Baxter Geog 215325
Slide 26
Trends in Criteria Air Contaminants over Time 10/14/2013 20:05
Baxter Geog 215326 Ground Level Ozone Emissions Canada
Slide 27
Acid Deposition SO 2 +/or NO x + H 2 O vapor H 2 SO 4 orHNO x
(sulfuric acid) (nitrate acids) Sources : long range transport of
air pollutants (LRTAP) Negative impacts: acidification of water
bodies, plants e.g. sugar maples, limestone structures 10/14/2013
20:05 Baxter Geog 215327
Slide 28
Trends in Canadas GHG Emissions 10/14/2013 20:05 Baxter Geog
215328
Slide 29
Exercise: Speed Search and Summarize Policy Levers for
Regulating GHGs Sort yourselves into groups of 4 but ensure at
least one member has a web-enabled device preferably a laptop Each
group come up with 4 key factual bullet points and your groups
opinion on the following topic: Cap and trade (all groups on left
half of room) Carbon tax (all groups on right half of room) You
have about 10 minutes then we will share what you found See slides
here after the discussion.slides here 10/14/2013 20:05 Baxter Geog
215329
Slide 30
Future Challenges Predicting Climate Change: General
Circulation Models (GCMs) Incomplete knowledge base Canadas
reliance on fossil fuels Canadians and cars What do you see as the
most significant challenge and why? 10/14/2013 20:05 Baxter Geog
215330
Slide 31
Review Which of the following is not a criteria air
contaminant? 10/14/2013 20:05 Baxter Geog 215331 Text a code to
37607 a)Sulphur Oxides (SO x ) 82012 b)Particulate Matter (PM)
82013 c)Chlorofluorocarbons (CFCs) 82014 d)Carbon Monoxide (CO)
82018 e)Ammonia (NH 3 ) 82034 Or Respond at this linkthis link poll
results here No peeking back up the notes
Slide 32
Review Stratospheric O3 is generally considered good while
tropospheric O3 is generally considered bad? 10/14/2013 20:05
Baxter Geog 215332 Text a code to 37607 a)True 106560 b)False
106571 Or Respond at this linkthis link poll results here No
peeking back up the notes
