ENV100 Chap 13-14

ENV100 - Chapter 13: Global Climate Change

Lecture Topics: Evidence of Climate Change, Causes, Impacts, Feedbacks, and Solutions
Textbook Chapter: Chapter 13 – "Global Climate Change"
Integrated with Lecture Slides: ENV100 Climate Change (Fall-Winter 2024-2025)

1. Overview and Definitions

  • Climate change refers to long-term changes in temperature, precipitation, and other atmospheric conditions.

  • Global warming is one aspect: a rise in Earth’s average surface temperature due to increased greenhouse gas concentrations.

2. Greenhouse Gases and the Greenhouse Effect

  • The natural greenhouse effect keeps Earth habitable.

  • Key greenhouse gases (GHGs):

    • Natural: CO₂, CH₄, N₂O, water vapor, ozone

    • Anthropogenic: CO₂ (fossil fuels, deforestation), CH₄ (agriculture, landfills), N₂O (fertilizers), CFCS, HFCS

  • Over 90% of the excess heat from GHGs is stored in oceans.

3. Scientific Consensus and IPCC Findings

  • IPCC (2021) confirms human influence as the dominant driver of recent warming.

  • Global temperature is now ~1.1–1.2°C above pre-industrial levels.

  • Sea level rise has tripled since 1901–1971.

  • Extreme heat events are more frequent; cold extremes are decreasing.

4. Physical and Ecological Impacts

  • Cryosphere: Melting glaciers, Arctic sea ice, and polar ice caps → sea level rise and albedo loss.

  • Hydrosphere:

    • Increased evaporation and altered precipitation patterns

    • Ocean warming, acidification, and changes in circulation

  • Biosphere:

    • Shifts in species ranges, extinctions, and disrupted food webs

    • Threats to ecosystem services (carbon sequestration, coastal protection)

5. Positive Feedback Loops

  • Melting ice → lower albedo → more absorption of heat

  • Thawing permafrost → releases methane (CH₄)

  • Warming oceans → absorb less CO₂

6. Social and Economic Impacts

  • Food and water insecurity due to shifting growing seasons, droughts, and floods

  • Human health risks: heat stress, air quality, vector-borne diseases

  • Climate migration and displaced populations

  • Economic costs from disasters, infrastructure damage, and loss of livelihoods

7. Climate Models and Scenarios

  • Climate models simulate past and future trends

  • Scenarios depend on future emissions.

    • RCP2.6 to RCP8.5: varying degrees of radiative forcing

    • SSPS (Shared Socioeconomic Pathways) used alongside RCPS

8. Climate Action and Mitigation Strategies

  • Reduce emissions:

    • Renewable energy, electrification, carbon pricing (taxes, cap-and-trade)

    • Reforestation and soil carbon storage

    • Sustainable agriculture and waste reduction

  • Geoengineering (controversial): solar radiation management, carbon dioxide removal

9. Adaptation Measures

  • Flood protection, urban greening, early warning systems, and resilient infrastructure

  • Water conservation, crop diversification, heat-health action plans

  • Adaptation is essential even with strong mitigation.

10. International Agreements

  • UNFCCC (1992): Framework for global cooperation

  • Kyoto Protocol (1997): Legally binding for developed nations

  • Paris Agreement (2015):

    • Goal: limit warming to below 2°C, pursue 1.5°C

    • Emissions targets via Nationally Determined Contributions (NDCS)

    • Emphasizes transparency, equity, and adaptive funding

11. Canadian Context

  • Canada is warming at 2× the global rate

  • Impacts:

    • Arctic ice melt, permafrost thaw, wildfires (e.g., 2023 wildfire season)

    • Indigenous communities are disproportionately affected

  • National initiatives:

    • Federal carbon pricing, net-zero by 2050 goals

    • Climate adaptation plans and Indigenous partnerships

12. Climate Justice and Equity

  • Disproportionate impact on vulnerable and low-income populations

  • Emphasis on climate justice:

    • Recognizing historical responsibility

    • Ensuring fair transition and inclusive policies

ENV100 - Chapter 14: Fossil Fuels and Energy

Lecture Topics: Conventional and Unconventional Fossil Fuels, Energy Use, Extraction, Impacts, and Policy
Textbook Chapter: Chapter 14 – "Fossil Fuels and Energy"
Integrated with Lecture Slides: ENV100 Fossil Fuels (Fall-Winter 2024-2025)

1. Introduction to Energy

  • Energy: The capacity to do work (move matter, cause change)

  • Power: Rate of energy use (watts = joules/sec)

  • Energy = Power × Time

  • kWh: Common household energy unit (1 kw of power used for 1 hour)

2. Energy Sources

  • Nonrenewable:

    • Fossil fuels: coal, oil, natural gas (formed from ancient organisms)

    • Nuclear energy (uranium)

  • Renewable:

    • Biomass (fuelwood, crop waste)

    • Hydropower, solar, wind, geothermal, tidal

  • Inexhaustible:

    • Solar and geothermal: vast potential but limited by technology and economics

3. Global Energy Use Trends

  • ~80% of global primary energy still comes from fossil fuels

    • 39% oil, 33% coal, 28% natural gas

  • Fossil fuel use has doubled since 1980

  • Growing consumption driven by middle-income countries

4. Fossil Fuel Formation

  • Organic matter decomposed under anaerobic conditions, buried and compressed

  • Kerogen: Intermediate product → converts into oil and gas under heat and pressure

  • Timeframe: 300–600 million years

5. Coal

  • Most abundant fossil fuel; formed from plant material in ancient swamps

  • Types (increasing carbon, decreasing moisture): peat → lignite → bituminous → anthracite

  • Extraction:

    • Surface mining (strip mining, mountaintop removal)

    • Subsurface mining (tunnels)

  • Uses: Mainly electricity generation

  • Impacts: Air pollution (SO₂, NOx, particulates), habitat destruction, acid mine drainage

6. Oil and Natural Gas

  • Formed from marine plankton in ancient seas

  • Oil = liquid hydrocarbons

  • Natural gas = methane-rich gas (CH₄)

  • Extraction:

    • Drilling wells, offshore rigs

    • Fracking for shale gas/oil (unconventional)

  • Uses:

    • Oil: transport fuels, plastics, petrochemicals

    • Natural gas: heating, electricity, fertilizer

  • Impacts: Oil spills, methane leakage, GHG emissions

7. Unconventional Fossil Fuels

  • Oil sands (bitumen + sand/clay)

    • High energy + water input, habitat loss (esp. Alberta)

  • Shale gas/oil: Extracted using hydraulic fracturing (fracking)

    • Water contamination, seismic activity, and methane emissions

  • Methane hydrates: Ice-trapped methane on the seafloor — not yet commercially viable

8. Energy Return on Investment (EROI)

  • EROI = Energy output / Energy input

    • Higher EROI = better energy yield

    • Fossil fuel EROI is declining over time as easy-to-access sources are depleted

9. Environmental and Social Concerns

  • Air pollution: SO₂, NOx, CO₂, particulate matter

  • GHG emissions → global warming

  • Land use: Mining, pipelines, infrastructure

  • Water use: Cooling, fracking, spills

  • Indigenous rights and environmental justice

10. Energy Policy and Transition

  • Policies address:

    • Energy security, emissions, and economic development

  • Subsidies still support fossil fuel industries

  • Transition involves:

    • Investing in renewables

    • Phasing out fossil fuel infrastructure

    • Just transition for fossil fuel workers

11. Canadian Context

  • Canada is a top oil and gas exporter (esp. Alberta)

  • Oil sands: Significant economic driver and environmental concern

  • Pipelines (e.g., Trans Mountain) face Indigenous opposition

  • Commitments to reduce emissions often conflict with continued fossil fuel expansion