GEOG 101: DAY 16Air Pollution (cont’d); Climate Change

The Spittelau incineration plant in Vienna, Austria, designed by Friedensreich Hundertwasser.

HOUSEKEEPING ITEMS

Consumer diesel vehicles are much cleaner in terms of particle emissions (PM-10 and PM-2.5), but big freight trucks and the like are still dirty.

Incinerator technology varies in its effectiveness. Wikipedia has a good description of the pros and cons and challenges of waste-to-energy and incineration: http://en.wikipedia.org/wiki/Incineration

Mercury is partly introduced into the environment by humans, but it is also there naturally, leaches out and bioaccumulates.

LCAs are due today if you did one. Check out the notes on-line, as I had a rare

opportunity to show you a very interesting video today that pulls a lot of threads we’ve been discussing together and also touches on climate change.

ACID DEPOSITION IS ANOTHER TRANSBOUNDARY POLLUTION PROBLEM

Acidic deposition = the deposition of acid, or acid-forming pollutants, from the atmosphere onto Earth’s surface Acid rain = precipitation of acid Atmospheric deposition = the wet or dry

deposition on land of pollutants Originates from burning fossil fuels

release sulfur dioxide and nitrogen oxides react with water to form sulfuric and nitric acids

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SOURCES OF ACID DEPOSITION 14-4

ACID DEPOSITION IS ANOTHER TRANSBOUNDARY POLLUTION PROBLEM (CONT’D)

Rain and other forms of precipitation with pH of less than 5.1 are considered acidified

Acidic deposition can have wide-ranging, cumulative detrimental effects on ecosystems and on our built environmentAcids leach nutrients from the topsoilAlters soil chemistry harming plants Mobilizes toxic metal ionsRun-off into surface watersErodes and corrodes built structures (Parthenon)

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ACID DEPOSITION HAS NOT BEEN REDUCED AS MUCH AS SCIENTISTS HAD HOPED

New technologies such as scrubbers have helped SO2 emissions are lower NOx emissions are higher Acid deposition’s effects are worse than predicted

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INDOOR AIR POLLUTION

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INDOOR AIR POLLUTION

Indoor air contains higher concentrations of pollutants than outdoor air

6,000 people in North America die per day from indoor air pollution

The average person in North America is indoors at least 90% of the time

Exposed to synthetic materials (insecticides, cleaning fluids, plastics, and chemically treated wood)

1973-74: ventilation systems were sealed off and windows put in that did not open, trapping pollutants inside

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INDOOR AIR POLLUTION IN THE DEVELOPING WORLD ARISES FROM FUELWOOD BURNING

Burning wood, charcoal, dung, crop wastes for cooking and eating Kills 1.6 million people each year Causes pneumonia, bronchitis, allergies, cataracts,

asthma, heart disease, cancer and premature death

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TOBACCO SMOKE AND RADON ARE THE MOST DANGEROUS INDOOR POLLUTANTS IN THE DEVELOPED WORLD

Secondhand smoke from cigarettes is especially dangerous Containing over 4000 dangerous chemicalsCauses eye, nose, and throat irritationSmoking has declined in developed nations

After cigarette smoke, radon gas is the second-leading cause of lung cancer in the developed worldColourless, odourless gas that can seep into buildings

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MANY VOCS POLLUTE INDOOR AIR

VOCs = volatile organic compounds Released by everything from plastics and oils to

perfumes and paints Most VOCs are released in very small amounts Unclear health implications due to low

concentrations Also include pesticides, which are found indoors

more often than outdoors due to seepage Formaldehyde, which leaks from pressed wood

and insulation, irritates mucous membranes and induces skin allergies

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LIVING ORGANISMS CAN POLLUTE INDOORS

Tiny living organisms can also pollute Includes dust mites and animal dander worsen

asthma Fungi, mold, mildew, airborne bacteria cause severe

allergies, asthma, and other respiratory ailments Sick building syndrome = a sickness produced

by indoor pollution with general and nonspecific symptoms Solved by using low-toxicity building materials and good

ventilation

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LIVING ORGANISMS CAN POLLUTE INDOOR SPACES

Dust mites and animal dander Fungi, mould, and mildew Airborne bacteria (Legionnaire’s disease) Microbes that induce allergic responses are thought

to be a major cause of sickness produced by indoor pollution Sick-building syndrome

HOW SAFE IS YOUR INDOOR ENVIRONMENT?

Think about the amount of time you spend indoors. Name the potential indoor air quality hazards in your home, work, or school environment.

What could you do to make the indoor spaces you use safer?

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weighing

the issues

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WE CAN REDUCE INDOOR AIR POLLUTION

In developed countries:Use low-toxicity materials (there

are stores and brands that specialize in this now)

Monitor air qualityKeep rooms cleanLimit exposure to chemicals

In developing countries:Dry wood before burningCook outside (including with

solar cookers)Use less-polluting fuels (natural

gas)

CONCLUSION

Indoor air pollution is a potentially serious health threat

Outdoor air pollution has been addressed by government legislation and regulation in developed countries, but is still a problem

Improvement is required in reducing acidic deposition, photochemical smog

Avoiding unhealthy pollutants in developing world will pose a challenge as less-wealthy nations industrialize; indeed air pollution is getting worse

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© 2010 Pearson Education Canada

15Global Climate Change

PowerPoint® Slides prepared by Stephen Turnbull

Copyright © 2013 Pearson Canada Inc.

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Final exam will be Thursday, December 4th in the Gym

HOUSEKEEPING ITEMS

A couple of links on Vancouver Island’s ocean acidification problem: http://www.vancouversun.com/life/Acidic+water+blamed+West+Coast+scallop/9550861/story.html and http://www.cbc.ca/news/canada/british-columbia/acidic-ocean-deadly-for-vancouver-island-scallop-industry-1.2551662.

Check out the following film: www.filmsforaction.org/watch/wake_up_freak_out_then_get_a_grip/.

UPON SUCCESSFULLY COMPLETING THIS CHAPTER, YOU WILL BE ABLE TO

Describe Earth’s climate system and explain the many factors influencing global climate change

Characterize human influences on the atmosphere and global climate

Summarize modern methods of climate research Outline current and future trends and impacts of

global climate change Suggest ways we can respond to climate change

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CENTRAL CASE: THE RETREAT OF THE ATHABASCA

The Athabasca Glacier has been retreating since 1844

Since then, it has lost half of its volume Currently retreating at a rate of 2-3 metres per year Is it retreating due to climate change or is it just a

natural continuation of the retreat of glacial ice that began 12,000 years ago?

The Rockies may be ice-free by the end of this century

“We’re in a giant car heading towards a brick wall and everyone’s arguing over where they’re going to sit.”

– David Suzuki

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OUR DYNAMIC CLIMATE

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OUR DYNAMIC CLIMATE

Climate influences everything around us The Fourth Assessment Report of the

Intergovernmental Panel on Climate Change (IPCC) made it clear that: Climate is changing, we are the cause, and this

change is already exerting impacts that will become increasingly severe if we do not take action

The Fifth is now out. Climate change is the fastest-moving area of

environmental science today, and the Fifth Report is now out and is even more urgent in its assessment and recommendations. Scientists, normally mere observers, are saying action has to happen now!

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WHAT IS CLIMATE CHANGE?

Climate = an area’s long-term atmospheric conditionsTemperature, moisture content, wind, precipitation,

etc. Weather = conditions at localized sites over hours or

days Global climate change = describes trends and

variations in Earth’s climateTemperature, precipitation, storm frequency

Global warming = an increase in Earth’s average temperatureEarth’s climate has varied naturally through timeThe rapid climatic changes taking place now are due

to human activity: fossil fuels, combustion, and deforestation

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THE SUN AND ATMOSPHERE KEEP EARTH WARM Four factors exert more influence on climate

than all others: The Sun (supplies planet’s energy) The atmosphere (absorbs 70% of incoming solar

radiation) The oceans (shape climate by storing and

transporting heat and moisture) Albedo = reflectivity of a surface (positive feedback

cycle of melting polar ice caps and ice sheets)

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OUR PLANET ABSORBS SOLAR RADIATION (SOLAR BUDGET)

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GREENHOUSE GASES WARM THE LOWER ATMOSPHERE As Earth’s surface absorbs solar radiation, the

surface increases in temperature and emits infrared radiation (for a good description overall, see NASA’s site: http://missionscience.nasa.gov/ems/13_radiationbudget.html.)

Greenhouse gases = atmospheric gases that absorb infrared radiation (radiatively active gases) Water vapor, ozone, carbon dioxide, nitrous oxide,

methane, chlorofluorocarbons (CFCs) Greenhouse gases differ in their ability to warm the

troposphere and surface

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GREENHOUSE GASES WARM THE LOWER ATMOSPHERE (CONT’D)

After absorbing radiation, greenhouse gases re-emit infrared energy Some energy is lost to space Greenhouse effect = some energy travels back

downward, warming the troposphere and the planet’s surface

Global warming potential = the relative ability of one molecule of a given greenhouse gas to contribute to warming Expressed in relation to carbon dioxide (potential =

1) Nitrous oxide is 296 times as potent as carbon

dioxide

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CARBON DIOXIDE IS THE ANTHROPOGENIC GREENHOUSE GAS OF PRIMARY CONCERN

Not the most potent greenhouse gas, but it is extremely abundant The major contributor to global

warming Human activities have boosted

atmospheric concentrations from 280 parts per million (ppm) to 389 ppm in 2010 (and now over 400)

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HUMAN ACTIVITY HAS RELEASED CARBON FROM SEQUESTRATION IN LONG-TERM RESERVOIRS

Human activities accelerate the fluxes of material from one reservoir to another in biogeochemical cycles Burning fossil fuels transfers CO2 from lithospheric

reservoirs into the atmosphere Deforestation transfers CO2 from terrestrial reservoirs

into the atmosphere Sinks = reservoirs that accept more of the material

than they release Ocean

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OTHER GREENHOUSE GASES CONTRIBUTE TO WARMING

Methane from fossil fuel deposits, livestock, landfills, and crops such as rice

Nitrous oxide from feedlots, chemical manufacturing plants, auto emissions, and synthetic nitrogen fertilizers

Ozone from photochemical smog Halocarbons (CFCs and HFCs) Water vapor = the most abundant greenhouse

gas and contributes most to the greenhouse effect

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THERE ARE MANY FEEDBACK CYCLES IN THE CLIMATE SYSTEM

Positive feedback cycle Warming leads to water vapour which leads to further

warming causing still more evaporation, and so on Negative feedback cycle

Warming leads to evaporation which leads to water vapour causing increased cloudiness slowing global warming

Aerosols = microscopic droplets and particles that have either a warming or cooling effect

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RADIATIVE FORCING EXPRESSES CHANGE IN ENERGY INPUT OVER TIME

Radiative forcing = the amount of change in energy that a given factor causes Positive forcing warms

the surface; negative forcing cools it

Compared with the pre-industrial Earth, Earth is experiencing radiative forcing of 1.6 watts/m2

Enough to alter the climate

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THE ATMOSPHERE IS NOT THE ONLY FACTOR THAT INFLUENCES CLIMATE Milankovitch cycles = periodic changes in

Earth’s rotation and orbit around the Sun Solar output = drives temperature change on

Earth’s surface Ocean absorption = the ocean holds 50 times

more carbon than the atmosphere and absorbs it from the atmosphere (acts as a sink)

Ocean circulation = ocean water exchanges tremendous amounts of heat with the atmosphere, and ocean currents move energy from place to place Thermohaline circulation

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IN ATLANTIC, WARMER SURFACE WATER FLOWS NORTH (E.G. THE GULF CURRENT), COOLS AND SINKS, FORMING THE NORTH ATLANTIC DEEP WATER (NADW)

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THE SCIENCE OF CLIMATE CHANGE

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• Proxy indicators = types of indirect evidence that serve as substitutes for direct measurements

- Ice caps, ice sheets, and glaciers hold clues to past climate

- Trapped bubbles in ice cores show atmospheric composition, greenhouse gas concentration, temperature trends, snowfall, solar activity, and frequency of fires

Proxy indicators tell us about the past

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DIRECT ATMOSPHERIC SAMPLING TELLS US ABOUT THE PRESENT

Atmospheric carbon dioxide concentrations have increased from 315 ppm in 1958 to 401 ppm in 2013

There are seasonal variations in levels due to photosynthetic uptake More carbon dioxide absorbed during northern

summer

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MODELS HELP US UNDERSTAND CLIMATE

Climate models simulate climate processes

Use information about: atmospheric

circulation ocean circulation interactions feedback

mechanisms

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MODELS HELP US UNDERSTAND CLIMATE (CONT’D)

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• Effectiveness of models are tested by entering data from the past and running the model toward the present

CURRENT AND FUTURE TRENDS AND IMPACTS

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CURRENT AND FUTURE TRENDS AND IMPACTS

Evidence that climate conditions have changed since industrialization is now overwhelming and indisputable

The way each of us experiences these impacts will vary tremendously

The impacts on Canada could be particularly severe, depending on where we live, though it should be pointed out that other nations have already been harder hit – the Maldives, Bangladesh, Australia, even parts of the U.S.

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THE IPCC SUMMARIZES EVIDENCE OF CLIMATE CHANGE AND PREDICTS FUTURE IMPACTSTrend = a pattern that persists within a data set,

even after short-term fluctuations and anomalies have been accounted for

Intergovernmental Panel on Climate Change (IPCC) 2013: Fifth Assessment Report

Consensus of scientific climate research from around the world

Trends in surface temperature, precipitation patterns, snow and ice cover, sea levels, storm intensity, and other factors

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TEMPERATURE INCREASES WILL CONTINUE

The IPCC report concludes that average surface temperatures on earth have been rising since 1906, with most of the increase occurring in the last few decades (0.74 R C)

Fifteen years from 1997-2011 among the 20 warmest years on record

Permafrost = perennially frozen ground Thawing in the ArcticPotentially releasing methane

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PROJECTED INCREASES IN SURFACE TEMPERATURE

More frequent heat waves Temperature change will vary by

region Stronger storms

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Kyoto successes (blue) and failures (red) – including the effects of land use – see The Guardian: (this was the web site I was looking for)http://www.theguardian.com/environment/blog/2012/nov/26/kyoto-protocol-carbon-emissions

CLIMATE CHANGE AND HUMAN RIGHTS

In December 2005, a group representing North America’s Inuit sent a legal petition to the Inter-American Commission on Human Rights, demanding that the United States restrict its greenhouse gas emissions, which the Inuit maintained were destroying their way of life in the Arctic. After a year, the commission dismissed the petition with a terse three-sentence letter. Do you think Arctic-living people deserve compensation from industrialized nations whose emissions have caused climate change that has disproportionately affected the Arctic? Do you think climate change can be viewed as a human rights issue? What ethical issues, if any, do you think climate change presents? How could these best be resolved?

weighing

the issues

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CHANGES IN PRECIPITATION WILL VARY BY REGION

Some regions are receiving more precipitation than usual, and others are receiving less

Droughts have become more frequent and severe (e.g. California and Australia) Harming agriculture, promoting soil erosion, reducing

drinking water supplies, and encouraging forest fires Heavy rains have contributed to flooding (UK and

Bangladesh)

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PROJECTED CHANGES IN JUNE-AUGUST PRECIPITATION, 2090-2099

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MELTING ICE AND SNOW HAVE FAR-REACHING EFFECTS Mountaintop glaciers are disappearing (“Glacier Park”

may soon become a misnomer) Have lost an average of 14 m since 1980 Risks of sudden floods as ice dams burst Reducing summertime water supplies

As ice melts, darker, less-reflective surfaces are exposed and absorb more sunlight, causing more melting

Melting permafrost makes slopes unstable and could release soil gases leading to further warming

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THE ARCTIC IS CHANGING DRAMATICALLY

Less snow cover Melting immense ice sheets (Greenland ice sheet):

http://earthsky.org/earth/video-largest-glacier-calving-ever-caught-on-film

Canada’s ice shelves have shrunk by 90% over the past 100 years (Ayles Ice Shelf)

Warming is accelerating as snow and ice melt, darker, less-reflective surfaces are

exposed Earth’s capacity to reflect light decreases

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RISING SEA LEVELS WILL AFFECT HUNDREDS OF MILLIONS OF PEOPLE AND COASTAL ZONES

As glaciers and ice melt, increased water will flow into the oceans

As oceans warm, they expand

See “Island President” (film)

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AN ICE-FREE NORTHWEST PASSAGE AND CANADA’S ARCTIC SOVEREIGNTY

Now that the Northwest Passage – the long-coveted sea route from the Atlantic to the Pacific via the Arctic Ocean – may soon be ice-free, northern nations are anxious to confirm its sovereignty over Arctic waters at an international conference held in Greenland recently, and Prime Minister Stephen Harper pledged to spend billions of dollars defending Canada’s interests in the Arctic if necessary. In addition to the sea route, the Arctic subsurface may hold as much as 25% of the world’s undiscovered oil and gas reserves.

The U.S. argues that the High Arctic does not belong to Canada, or to anyone else. What do you think? Who should control Arctic Ocean waters, and for what purposes? How much of Canadian taxpayers’ money should be spent to assert and maintain Canada’s sovereignty in the Arctic?

weighing

the issues

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CLIMATE CHANGE AFFECTS ORGANISMS AND ECOSYSTEMS

Global warming modifies temperature-dependent phenomenaTiming of migration, breeding

Spatial shifts in the range of organismsAnimals and plants will move towards the poles

or upward in elevation20-30% of all species will be threatened with

extinction Plants act as carbon sinks; fewer plants means

more CO2 in the atmosphere

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ENVIRONMENTAL REFUGEES?

The Pacific island nation of Tuvalu has been losing 9 cm of elevation per decade to rising seas. Appeals from Tuvalu’s 11,000 citizens were heard by New Zealand, which began accepting them in small numbers as of 2003, although the government has not officially categorized them as environmental refugees – people driven from their homelands as a result of environmental change or natural disaster. Tuvaluans have been particularly vocal about global warming, but several other small Pacific island nations have joined in voicing their concerns.

Will there come a time when neighbouring countries should begin to treat people who leave small island nations as environmental refugees? Should they be doing it now? What will happen to these people after relocation – do you think a national culture can survive if its entire population is relocated?

weighing

the issues

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CLIMATE CHANGE EXERTS SOCIETAL IMPACTS – AND VICE VERSA

Agriculture: growing seasons shortened, crops more susceptible; crop

production will decrease, worsening hunger Forestry:

increased insect and disease outbreaks, increased chance of forest fires (pine beetle larvae used to be killed by colder winter temperatures)

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CLIMATE CHANGE EXERTS SOCIETAL IMPACTS – AND VICE VERSA (CONT’D)

Health: heat waves can cause death, respiratory ailments,

expansion of tropical diseases, increased chance of drowning if storms become intense, hunger-related ailments

Economics: some costs and some benefits; costs will outweigh the

benefits, widen the gap between rich and poor, will cost roughly 5-20% of world GDP

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ARE WE RESPONSIBLE FOR CLIMATE CHANGE?

The IPCC concluded:It is more than 90% likely that most of the

global warming recorded over the past 50 years is due to the well-documented increase in greenhouse gas concentrations in our atmosphere

Today the debate concerning the human role in climate change is largely over

Shift in public perception Role of Al Gore’s 2006 “An Inconvenient Truth”

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RESPONDING TO CLIMATE CHANGE

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RESPONDING TO CLIMATE CHANGE

We will likely either keeping on pursuing economic growth at all costs, which will require more and more resources to fix the damage (what ecological economists call ‘dis-economies of scale’), and will eventually lead to social, economic, and population crash, or

We will make sustainability our first priority, aim for a ‘soft landing’ and create a steady-state economy.

Is this even possible? It’s like going from believing the Earth is flat to believing that it is round.

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SHALL WE PURSUE MITIGATION OR ADAPTATION, OR INTERVENTION?

Mitigation = pursue actions that reduce greenhouse gas emissions, in order to lessen severity of future climate change Renewable energy sources, farm practices to protect

soil integrity, preventing deforestation

Adaptation = accept climate change is happening and pursue strategies to minimize its impacts on us Criticized as sidestepping

Both are necessary

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SHALL WE PURSUE MITIGATION OR ADAPTATION, OR INTERVENTION? Intervention = set of possible large-scale

technological modifications to the global climate system

Causes of concern: Interfering with global-scale Earth’s systemsAbandon mitigation efforts

Geo-engineering – grand scale intervention (for more information, see http://www.scientificamerican.com/article/geoengineering-to-save-the-world-from-global-warming/ and other sources in Google Increase fluxes of greenhouse gasesReduce incoming solar radiation

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WE CAN LOOK MORE CLOSELY AT OUR LIFESTYLE

Conservation and efficiency High-efficiency light bulbs and appliances Reduce electricity consumption Life-style choices

Sources of electricity Alter types of energy we use Natural gas cleaner than oil; oil cleaner than coal

Carbon capture and storage = remove CO2 from power plant emissions

Other?

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TRANSPORTATION IS A SIGNIFICANT SOURCE OF GREENHOUSE GASES; LIKEWISE BUILDINGS

Automotive technology• make vehicles more fuel-efficient, hybrid cars

Driving less and using public transportation Public transportation is the most effective way to

conserve energy, reduce pollution Live nearer your workplace, so you can bike or walk

(http://www.walkscore.com/)

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CONVENTIONAL CARS ARE EXTREMELY INEFFICIENT

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WE CAN REDUCE EMISSIONS IN OTHER WAYS AS WELL Use advances in agriculture, forestry, and waste

management Grow renewable biofuels (or produce from waste

vegetable oil) Rapid reforestation of deforested areas Recovering methane from landfills Recycling, composting, and reduction or reuse of

materials

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WE WILL NEED TO FOLLOW MULTIPLE STRATEGIES TO REDUCE EMISSIONS

There is no single ‘magic bullet’ for mitigating climate change

Most reductions can be achieved using current technology so we can begin right away

How quickly and successfully we translate science and technology into practical solutions for reducing emissions depends on policies and the market economy or, one might argue, taming the market economy and the corporations that dominate it – especially the oil companies

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WE BEGAN TACKLING CLIMATE CHANGE BY INTERNATIONAL TREATY

UN Framework Convention on Climate Change (FCCC) = outlines a plan for reducing greenhouse gas emissions to 1990 levels by the year 2000 through a voluntary, nation-by-nation approach By the late 1990s, it was clear that the voluntary

approach would not succeed (few met their targets)

Developing nations created a binding international treaty that would require all signatory nations to reduce their emissions

However, subsequent rounds of talks have proven relatively fruitless (“prisoner’s dilemma”)

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It’s curious the Danes would be amongst the failing nations – they lead the world in wind energy, and they ride more bicycles per capita than anyone else!?

WE BEGAN TACKLING CLIMATE CHANGE BY INTERNATIONAL TREATY (CONT’D)

The Kyoto Protocol by 2012 nations were to reduce emissions of six

greenhouse gases to levels below those of 1990 took effect in 2005, after Russia became the 127th nation

to ratify it; Canada withdrew in 2011 The United States will not ratify the Kyoto Protocol

Did not require same of countries of China and India Businesses in industrialized nations feel they have

more to lose economically from restrictions

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Carbon taxes (e.g., B.C. – since weakened) Permit trading programs

harness the economic efficiency of the free market to achieve policy goals

The Chicago Climate Exchange is the world’s first emissions trading program for greenhouse gas reduction

Cap-and-trade programs European Union Emission Trading Scheme

Market mechanisms are being used to address climate change

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CARBON OFFSETS ARE IN VOGUE

Carbon offset = a voluntary payment to another entity intended to enable that entity to reduce the greenhouse emissions that one is unable or unwilling to reduce oneself Popular among utilities, businesses, universities,

governments, and individuals trying to achieve carbon neutrality

Carbon-neutrality = no net carbon is emitted, as with certain housings, buildings, and developments

Carbon offsets fall short A lack of oversight to make sure that the offset

money accomplishes what it is intended for

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YOU CAN REDUCE YOUR OWN CARBON FOOTPRINT

Carbon footprint = expresses the amount of carbon we are responsible for emitting (see How Bad Are Bananas? The Carbon Footprint of Everything by Mike Berners-Lee). To calculate yours, see http://cotap.org/carbon-footprint-calculator/.

What do you think you can do to make a difference? What about in relation to politicians and

corporations? Global climate change may be the biggest

challenge facing us and our children Taking immediate action is the most important

thing we can do

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CONCLUSION

Many factors influence Earth’s climateHuman activities play a major role

Climate change is well underwayFurther emissions will cause severe and diverse

impacts More and more scientists are urging immediate

actionReducing emissionsMitigating and adapting to a changing climate

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