Climate change is a pressing global issue that demands urgent action. Greenhouse gases trap heat, causing global warming and various environmental impacts. Mitigation strategies aim to reduce emissions through carbon pricing, regulations, and innovation support.
Adaptation involves adjusting to climate change effects across sectors like water, agriculture, and infrastructure. International agreements like the set global goals, but current efforts are insufficient to limit warming to safe levels.
Climate Change Science and Impacts
Greenhouse Effect and Global Warming
The greenhouse effect is a natural process where greenhouse gases in the atmosphere trap heat from the sun, warming the Earth's surface
Human activities have significantly increased greenhouse gas concentrations, intensifying this effect and causing global warming
Primary greenhouse gases include carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and water vapor (H2O)
CO2 is the most significant long-lived greenhouse gas
Atmospheric concentrations have increased from pre-industrial levels of 280 ppm to over 410 ppm today
Mainly due to burning fossil fuels (coal, oil, natural gas) and land use changes (deforestation)
Evidence and Potential Impacts of Climate Change
Climate change is evidenced by various observed changes in the Earth's climate system
Rising global average temperatures
Warming oceans
Shrinking ice sheets and glacial retreat
Decreased snow cover
Declining Arctic sea ice
Ocean acidification
More frequent (heatwaves, droughts, floods, hurricanes)
Potential impacts of climate change span across natural and human systems
More frequent and intense heatwaves, droughts, and floods
Rising sea levels threatening coastal communities and infrastructure
Ocean acidification harming marine ecosystems and fisheries
Ecosystem and biodiversity loss as species struggle to adapt to changing conditions
Reduced agricultural yields due to changing temperature and precipitation patterns
Spread of vector-borne diseases (malaria, dengue) as warmer temperatures expand the range of disease-carrying insects
Displacement of populations due to sea level rise, extreme weather events, and resource scarcity
Climate models project continued rise in global average temperature, with the magnitude dependent on future greenhouse gas emissions
Limiting warming to 1.5°C or 2°C above pre-industrial levels requires rapid and far-reaching transitions in energy, land, urban infrastructure, and industrial systems
Mitigation Strategies for Emissions
Carbon Pricing and Market-Based Instruments
Carbon pricing puts a price on greenhouse gas emissions, providing an economic incentive to reduce emissions
Two main forms are carbon taxes and emissions trading systems ()
Carbon taxes impose a tax on each unit of emissions ($/ton CO2), encouraging companies to reduce emissions to avoid paying the tax
Emissions trading systems set a cap on total emissions and allocate allowances to companies, which can then trade allowances among themselves
Creates a market price for emissions and incentivizes companies to reduce emissions to sell excess allowances or avoid having to purchase additional ones
Other market-based instruments include removal of fossil fuel subsidies and border carbon adjustments
Regulatory Approaches and Sectoral Policies
Regulations and standards can mandate emission reductions or adoption of cleaner technologies in specific sectors
Fuel economy standards for vehicles (CAFE standards in the US)
Energy efficiency standards for appliances and buildings (Energy Star program)
Renewable portfolio standards requiring a certain percentage of electricity to come from renewable sources
Sectoral policies target emission reductions in key emitting sectors
Power sector: mandates, coal phase-out policies, grid modernization
Transport sector: vehicle electrification, public transit expansion, land use planning
Buildings sector: green building codes, retrofit programs, appliance standards
Industry sector: energy efficiency improvements, process changes, material substitution
Agriculture and forestry sectors: sustainable land management practices, reducing deforestation, afforestation/reforestation
Supporting Innovation and Behavioral Change
Subsidies and incentives encourage deployment of low-carbon technologies and practices
Tax credits for renewable energy (Production Tax Credit, Investment Tax Credit)
Rebates for electric vehicles and energy-efficient appliances
Payments for carbon sequestration in agriculture and forestry (carbon farming)
Research, development, and deployment (RD&D) policies support innovation and commercialization of clean energy technologies
Government funding for basic research and pilot projects
Public-private partnerships to demonstrate and scale up new technologies
Technology transfer and intellectual property rights policies
Information and voluntary programs aim to change behavior by raising awareness and providing tools and resources
Energy efficiency labeling (EnergyGuide, Energy Star)
Green power purchasing options for consumers
Corporate reporting and voluntary emission reduction pledges
Adapting to Climate Change
Key Sectors and Adaptation Measures
Adaptation involves adjusting to actual or expected climate change effects to moderate harm or exploit beneficial opportunities
Can be incremental (maintaining the essence and integrity of a system) or transformational (changing the fundamental attributes of a system)
Key sectors for adaptation include:
Water resources: water efficiency measures, diversifying water sources, flood control infrastructure
Adaptation measures can be structural/physical (sea walls, irrigation systems), social (awareness raising, social protection), or institutional (land use planning, building codes)
Challenges and Opportunities
Challenges for adaptation include:
Uncertainty in local climate change impacts
Limited resources and capacity, especially in developing countries
Competing priorities for scarce resources
Maladaptation - actions that may lead to increased risk of adverse outcomes
Opportunities for adaptation include:
Mainstreaming adaptation into existing planning processes (infrastructure investment, land use planning, public health)
Harnessing synergies with sustainable development and poverty reduction
Capturing co-benefits such as improved air quality and public health
Ecosystem-based adaptation uses biodiversity and to help people adapt to climate change
Restoring coastal wetlands to buffer against storms and sea level rise
Planting trees in cities to reduce the urban heat island effect
Community-based adaptation empowers local communities to identify and implement adaptation strategies
Participatory planning processes
Integration of traditional knowledge
Locally-managed funds for adaptation investments
Effectiveness of Climate Agreements
Evolution of the International Climate Regime
The is an international environmental treaty adopted in 1992
Objective is to stabilize greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous human interference with the climate system
Establishes key principles such as common but differentiated responsibilities and respective capabilities
The , adopted in 1997 under the UNFCCC, was the first binding international agreement to reduce greenhouse gas emissions
Committed industrialized countries (Annex I Parties) to legally binding emission reduction targets
Introduced market-based mechanisms such as emissions trading, Clean Development Mechanism, and Joint Implementation
Had mixed success due to limited participation and lack of compliance mechanism
The Paris Agreement, adopted in 2015 under the UNFCCC, aims to strengthen the global response to climate change
Goal is to keep global temperature rise this century well below 2°C above pre-industrial levels and to pursue efforts to limit the increase to 1.5°C
Requires all Parties to put forward their best efforts through nationally determined contributions (NDCs)
Includes provisions on adaptation, finance, technology transfer, capacity building, and transparency
Assessment of Effectiveness and Future Prospects
Assessments show that current NDCs are insufficient to limit warming to 1.5°C or 2°C
Emissions gap between current NDCs and emission reductions needed to meet Paris Agreement goals
Many countries are not on track to meet their NDC targets
The Paris Agreement includes a ratcheting mechanism to increase ambition over time
Countries are expected to submit new or updated NDCs every five years
Each successive NDC should represent a progression beyond the previous one
Challenges remain in ensuring all countries implement their NDCs and in mobilizing sufficient finance and technology transfer to support developing countries
Opportunities exist to integrate climate action with other international frameworks and agendas
Sustainable Development Goals (SDGs) - many climate actions have co-benefits for SDGs such as affordable and clean energy, sustainable cities, and responsible consumption and production
Sendai Framework for Disaster Risk Reduction - integrating climate change adaptation with disaster risk reduction efforts
Convention on Biological Diversity (CBD) - ecosystem-based approaches to mitigation and adaptation can also support biodiversity conservation goals
Key Terms to Review (18)
Cap-and-Trade: Cap-and-trade is an environmental policy tool that aims to reduce greenhouse gas emissions by setting a limit (cap) on total emissions and allowing companies to buy and sell emission permits. This system encourages firms to innovate and reduce their emissions, as they can profit by selling unused allowances. The flexibility of trading creates economic incentives for companies to lower emissions while still meeting regulatory requirements.
Carbon capture and storage: Carbon capture and storage (CCS) is a technology that captures carbon dioxide emissions produced from the use of fossil fuels in electricity generation and industrial processes, preventing the gas from entering the atmosphere. This method not only helps mitigate climate change by reducing greenhouse gas emissions but also facilitates the transition to a more sustainable energy system. By capturing CO2 and storing it underground or utilizing it in various industrial applications, CCS plays a critical role in addressing the urgent need for climate change mitigation and adaptation efforts.
Carbon tax: A carbon tax is a financial charge imposed on companies and individuals for the greenhouse gas emissions they produce, particularly carbon dioxide. The main goal of this tax is to encourage reductions in carbon emissions by making fossil fuels more expensive, thereby promoting cleaner energy alternatives and supporting climate change mitigation efforts.
Climate Action Plans: Climate action plans are strategic frameworks developed by governments, organizations, or communities to outline their approach to addressing climate change. These plans typically include specific goals for reducing greenhouse gas emissions and measures for adapting to the effects of climate change, ensuring that a balanced approach to mitigation and adaptation is achieved.
Ecosystem Services: Ecosystem services are the benefits that humans receive from natural ecosystems, including provisioning, regulating, cultural, and supporting services. These services play a crucial role in human well-being and sustainability, connecting directly to how we manage natural resources and adapt to climate change. By recognizing the value of these services, societies can develop policies that protect ecosystems while enhancing their contributions to human life.
Environmental Justice: Environmental justice is the equitable treatment of all people, regardless of race, ethnicity, or socioeconomic status, in the development and enforcement of environmental laws and policies. It emphasizes that marginalized communities often bear the brunt of environmental hazards and seeks to address these disparities through advocacy, policy change, and community engagement. This concept connects to broader issues like climate change and environmental regulation by highlighting the need for fair access to resources and protections against harmful practices.
Extreme Weather Events: Extreme weather events are severe or unusual weather phenomena that can cause significant damage to the environment and human societies. These events include hurricanes, floods, droughts, heatwaves, and heavy snowfall, which have become increasingly frequent and intense due to climate change. Understanding these occurrences is essential for developing effective strategies for climate change mitigation and adaptation.
Infrastructure adaptation: Infrastructure adaptation refers to the process of modifying and upgrading physical structures and systems to better withstand the impacts of climate change and other environmental stresses. This concept is crucial as it aims to enhance resilience by ensuring that roads, bridges, water supply systems, and energy grids can function effectively despite changing climate conditions. As climate change continues to pose significant risks, infrastructure adaptation plays a vital role in safeguarding communities and maintaining economic stability.
Integrated Assessment Models: Integrated Assessment Models (IAMs) are tools that combine knowledge from multiple disciplines to evaluate the interactions between human and natural systems, particularly in the context of climate change. These models assess the impacts of climate policies on various socio-economic factors and the environment, helping decision-makers understand potential outcomes of different mitigation and adaptation strategies. By integrating data from economics, environmental science, and technology, IAMs support informed policy-making for addressing climate change challenges.
Intergovernmental Panel on Climate Change (IPCC): The Intergovernmental Panel on Climate Change (IPCC) is a scientific body established by the United Nations to assess the scientific knowledge about climate change and its impacts. The IPCC plays a crucial role in providing policymakers with comprehensive and up-to-date assessments of climate change, its effects, and potential mitigation and adaptation strategies to address this global issue.
Kyoto Protocol: The Kyoto Protocol is an international treaty that commits its parties to reduce greenhouse gas emissions, based on the premise that global warming exists and human-made CO2 emissions have caused it. Adopted in 1997 and enforced in 2005, this treaty represents a significant step in global climate change efforts, establishing legally binding targets for developed countries to decrease their emissions as part of a collective goal to mitigate climate change impacts.
Paris Agreement: The Paris Agreement is an international treaty adopted in 2015 aimed at combating climate change and its impacts by limiting global warming to well below 2 degrees Celsius above pre-industrial levels. This agreement establishes a framework for countries to set and achieve their climate goals, fostering a collective approach to mitigate greenhouse gas emissions while promoting sustainable development.
Policy Advocacy: Policy advocacy refers to the active support or argument for a particular policy change or initiative, aimed at influencing decision-makers and public opinion. It involves a variety of strategies, including lobbying, grassroots mobilization, and public campaigns, to push for specific outcomes that align with particular interests or values. Understanding policy advocacy is crucial as it intersects with various sectors, including environmental issues and the influence of organized groups on policymaking.
Renewable energy: Renewable energy refers to energy that is generated from natural processes that are continuously replenished, such as solar, wind, hydro, and geothermal sources. This type of energy is crucial in reducing dependence on fossil fuels and plays a significant role in achieving environmental sustainability while addressing climate change. By utilizing renewable energy sources, we can work toward sustainable development and mitigate the negative impacts of climate change, thereby supporting global initiatives for a cleaner and healthier planet.
Resilience Building: Resilience building refers to the process of enhancing the ability of individuals, communities, and systems to adapt to and recover from adverse situations, such as environmental changes or disasters. It focuses on improving adaptive capacities, ensuring that stakeholders can withstand shocks while minimizing vulnerability. This concept is particularly important in addressing the impacts of climate change, where communities must be prepared for extreme weather events and shifting environmental conditions.
Sea Level Rise: Sea level rise refers to the increase in the average level of the world's oceans, primarily caused by climate change and the melting of ice sheets and glaciers. This phenomenon poses significant risks to coastal ecosystems, human settlements, and infrastructure, requiring effective strategies for both mitigation and adaptation to manage its impacts.
Sustainability: Sustainability refers to the ability to meet present needs without compromising the ability of future generations to meet their own needs. It encompasses a balance between environmental health, economic viability, and social equity. This concept is crucial for achieving long-term goals that promote not just growth but also the well-being of communities and ecosystems over time.
United Nations Framework Convention on Climate Change (UNFCCC): The United Nations Framework Convention on Climate Change (UNFCCC) is an international treaty established in 1992 that aims to address the global challenge of climate change by reducing greenhouse gas emissions and promoting sustainable development. The UNFCCC sets a framework for negotiating specific agreements, including the Kyoto Protocol and the Paris Agreement, to facilitate climate change mitigation and adaptation efforts among its member countries.