aice environmental management unit 8 study guides

Key Concepts and Definitions

• Climate change refers to long-term shifts in global or regional climate patterns, primarily caused by human activities that increase greenhouse gas emissions
• Greenhouse gases (carbon dioxide, methane, nitrous oxide, water vapor) trap heat in the Earth's atmosphere, leading to a warming effect known as the greenhouse effect
• Global warming specifically refers to the increase in Earth's average surface temperature due to rising levels of greenhouse gases
  • Since the pre-industrial era, global temperatures have risen by approximately 1.1°C (2°F)
• Climate variability describes short-term fluctuations in climate patterns, such as El Niño and La Niña events, which can influence weather patterns and temperatures
• Anthropogenic climate change is caused by human activities, primarily through the burning of fossil fuels, deforestation, and land-use changes
• Climate feedback loops can amplify or dampen the effects of climate change
  • Positive feedback loops (melting Arctic ice exposing darker ocean waters) accelerate warming
  • Negative feedback loops (increased plant growth absorbing more carbon dioxide) slow warming
• Tipping points are thresholds beyond which abrupt and irreversible changes occur in the climate system (collapse of the West Antarctic Ice Sheet)

Causes and Sources of Climate Change

• Burning of fossil fuels (coal, oil, natural gas) releases carbon dioxide into the atmosphere, accounting for the majority of greenhouse gas emissions
• Deforestation and land-use changes remove carbon sinks and contribute to increased atmospheric carbon dioxide levels
  • Forests absorb and store carbon dioxide through photosynthesis, acting as important carbon sinks
  • Clearing forests for agriculture, logging, or urban development reduces the Earth's capacity to absorb carbon dioxide
• Agricultural practices, such as livestock farming and rice cultivation, produce methane emissions
  • Cattle and other ruminants release methane through enteric fermentation during digestion
  • Flooded rice paddies create anaerobic conditions that promote methane-producing bacteria
• Industrial processes and manufacturing contribute to greenhouse gas emissions through energy consumption and the use of chemicals (hydrofluorocarbons in refrigerants)
• Transportation, including cars, trucks, and airplanes, relies heavily on fossil fuels and contributes to carbon dioxide emissions
• Waste management practices, such as landfills, generate methane as organic waste decomposes under anaerobic conditions
• Positive feedback loops can amplify the effects of climate change
  • Melting permafrost releases stored methane and carbon dioxide, further enhancing the greenhouse effect

Global Impacts of Climate Change

• Rising sea levels due to thermal expansion of oceans and melting of land-based ice (glaciers, ice sheets) threaten coastal communities and low-lying islands
  • Increased coastal flooding, erosion, and saltwater intrusion into freshwater aquifers
  • Displacement of millions of people, creating climate refugees
• Changes in precipitation patterns, with some regions experiencing more frequent and intense droughts while others face increased flooding and heavy rainfall events
• Shifts in the distribution and abundance of plant and animal species as they adapt to changing climatic conditions
  • Some species may migrate to higher latitudes or elevations seeking suitable habitats
  • Increased risk of extinction for species unable to adapt or migrate quickly enough
• Ocean acidification occurs as oceans absorb excess carbon dioxide, lowering the pH of seawater and impacting marine ecosystems
  • Coral reefs, which are sensitive to changes in water chemistry, are particularly vulnerable
• Impacts on agriculture and food security, with changes in growing seasons, crop yields, and the spread of pests and diseases
• Increased frequency and intensity of extreme weather events, such as heatwaves, hurricanes, and wildfires
• Human health risks, including the spread of vector-borne diseases (malaria, dengue fever), heat stress, and respiratory issues due to air pollution and allergens

Mitigation Strategies

• Reducing greenhouse gas emissions is the primary goal of mitigation strategies to limit the extent of climate change
• Transitioning to renewable energy sources (solar, wind, hydro, geothermal) to replace fossil fuels in electricity generation and transportation
  • Increasing the share of renewable energy in the global energy mix
  • Implementing policies and incentives to encourage the adoption of renewable technologies
• Improving energy efficiency in buildings, industries, and appliances to reduce energy consumption and associated emissions
  • Implementing energy efficiency standards and labeling programs
  • Promoting the use of energy-efficient technologies (LED lighting, insulation, smart thermostats)
• Promoting sustainable transportation options, such as public transit, electric vehicles, and active transportation (cycling, walking)
• Implementing carbon pricing mechanisms, such as carbon taxes or cap-and-trade systems, to incentivize emissions reductions and encourage low-carbon investments
• Enhancing carbon sinks through afforestation, reforestation, and improved land management practices
  • Planting trees and restoring degraded forests to increase carbon sequestration
  • Adopting sustainable agricultural practices (reduced tillage, cover cropping) to store carbon in soils
• Developing and deploying carbon capture and storage technologies to capture emissions from industrial processes and power plants and store them underground
• Promoting changes in consumer behavior and lifestyle choices to reduce individual carbon footprints
  • Encouraging energy conservation, waste reduction, and sustainable consumption patterns

Adaptation Measures

• Adaptation involves adjusting to the impacts of climate change that are already occurring or are expected to occur in the future
• Developing and implementing early warning systems for extreme weather events (heatwaves, floods, hurricanes) to minimize loss of life and property damage
• Improving infrastructure resilience to withstand the impacts of climate change
  • Upgrading and reinforcing buildings, roads, and bridges to withstand more frequent and intense weather events
  • Constructing sea walls, levees, and other coastal protection measures to mitigate the effects of sea-level rise and storm surges
• Enhancing water management and conservation practices to address changes in water availability and quality
  • Implementing water-efficient irrigation techniques (drip irrigation, precision agriculture)
  • Promoting rainwater harvesting and water recycling to reduce pressure on freshwater resources
• Adapting agricultural practices to changing climatic conditions
  • Developing drought-resistant and heat-tolerant crop varieties
  • Adjusting planting and harvesting schedules to align with shifting growing seasons
• Protecting and restoring ecosystems that provide critical services and support biodiversity
  • Establishing protected areas and wildlife corridors to facilitate species migration and adaptation
  • Implementing ecosystem-based adaptation strategies (mangrove restoration, wetland conservation) to buffer against the impacts of climate change
• Improving public health systems and infrastructure to cope with climate-related health risks
  • Strengthening disease surveillance and response capacities
  • Developing heat action plans and cooling centers to protect vulnerable populations during heatwaves
• Promoting climate change education and awareness to build community resilience and encourage individual action

International Agreements and Policies

• The United Nations Framework Convention on Climate Change (UNFCCC) is the primary international treaty addressing climate change, adopted in 1992
  • Aims to stabilize greenhouse gas concentrations in the atmosphere at a level that prevents dangerous anthropogenic interference with the climate system
• The Kyoto Protocol, adopted in 1997, set legally binding emissions reduction targets for developed countries
  • Introduced market-based mechanisms (emissions trading, Clean Development Mechanism) to facilitate emissions reductions
• The Paris Agreement, adopted in 2015, aims to strengthen the global response to climate change by keeping global temperature rise well below 2°C above pre-industrial levels
  • Requires all parties to submit Nationally Determined Contributions (NDCs) outlining their emissions reduction targets and adaptation plans
  • Emphasizes the importance of climate finance, technology transfer, and capacity building to support developing countries
• The Intergovernmental Panel on Climate Change (IPCC) is the leading international scientific body for assessing climate change
  • Provides comprehensive assessments of the scientific, technical, and socio-economic aspects of climate change
  • Informs policymakers and supports international negotiations
• National and regional climate policies vary across countries, reflecting their specific circumstances and priorities
  • Examples include the European Union's Emissions Trading System (EU ETS), China's National Carbon Market, and the United States' Clean Power Plan
• Subnational and local governments also play a crucial role in implementing climate policies and actions
  • Cities and regions often set their own emissions reduction targets and develop climate action plans tailored to their local contexts

Technological Solutions

• Renewable energy technologies harness natural resources (solar, wind, hydro, geothermal) to generate electricity with minimal greenhouse gas emissions
  • Solar photovoltaic (PV) systems convert sunlight directly into electricity using solar panels
  • Wind turbines capture the kinetic energy of moving air to generate electricity
  • Hydroelectric power plants use the flow of water to turn turbines and generate electricity
• Energy storage technologies, such as batteries and pumped hydro storage, help balance the intermittency of renewable energy sources and ensure a stable electricity supply
• Electric vehicles (EVs) reduce transportation-related emissions by replacing internal combustion engines with electric motors powered by rechargeable batteries
  • Advances in battery technology have increased the driving range and affordability of EVs
• Smart grid technologies optimize the distribution and consumption of electricity, enabling the integration of renewable energy sources and demand-side management
  • Advanced metering infrastructure (smart meters) allows for real-time monitoring and control of energy consumption
• Energy-efficient technologies reduce energy consumption and associated emissions in various sectors
  • LED lighting is more energy-efficient and longer-lasting compared to traditional incandescent bulbs
  • High-efficiency appliances (refrigerators, air conditioners) consume less energy while providing the same level of service
• Carbon capture and storage (CCS) technologies capture carbon dioxide emissions from industrial processes or power plants and store them underground in geological formations
  • Pre-combustion, post-combustion, and oxy-fuel combustion are different approaches to CCS
• Negative emissions technologies (NETs) remove carbon dioxide from the atmosphere, helping to offset emissions that are difficult to eliminate
  • Direct air capture (DAC) uses chemical processes to extract carbon dioxide directly from the air
  • Bioenergy with carbon capture and storage (BECCS) combines biomass energy production with CCS to achieve net negative emissions

Future Projections and Challenges

• Climate models project a range of future global temperature increases depending on different emissions scenarios and the sensitivity of the climate system to greenhouse gases
  • The IPCC's Representative Concentration Pathways (RCPs) describe different emissions scenarios and their associated temperature projections
  • Under the high-emissions scenario (RCP8.5), global temperatures could rise by 3.2 to 5.4°C by 2100 compared to pre-industrial levels
• Sea-level rise is expected to continue and accelerate in the coming decades, with projections ranging from 0.3 to 1.1 meters by 2100 depending on the emissions scenario
  • The melting of the Greenland and Antarctic ice sheets could contribute significantly to sea-level rise, particularly if certain tipping points are crossed
• Extreme weather events, such as heatwaves, droughts, and heavy precipitation, are projected to become more frequent and intense in many regions
• Climate change impacts are expected to exacerbate existing social and economic inequalities, with developing countries and vulnerable populations being disproportionately affected
• Adapting to the impacts of climate change will require significant investments in infrastructure, technology, and capacity building, particularly in developing countries
• Limiting global warming to well below 2°C, as outlined in the Paris Agreement, will require rapid and far-reaching transitions in energy, land use, transportation, and industrial systems
  • Achieving net-zero emissions by mid-century is considered crucial to meeting this goal
• Political, economic, and social challenges can hinder the implementation of effective climate policies and actions
  • Lack of political will, vested interests in fossil fuel industries, and public resistance to lifestyle changes can slow down the transition to a low-carbon economy
• Addressing climate change requires a coordinated global effort, with all countries and stakeholders working together to reduce emissions, adapt to impacts, and support the most vulnerable