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Wyatt's Notes — IB

Climate Change

Climate Change

This section covers the IB Geography core extension on global climate — vulnerability and resilience. It examines the physical and human dimensions of climate change, including the evidence for global warming, the role of greenhouse gases, the impacts on different regions and communities, and the strategies societies can employ to adapt to and mitigate its effects. Students must be able to evaluate competing explanations, use case studies from contrasting locations, and apply geographic skills to climate data.

Contents

Overview

Climate change sits at the intersection of physical and human geography, making it one of the most synoptic topics in the IB Geography course. It requires students to integrate understanding of atmospheric systems and biogeochemical cycles with analysis of policy responses, economic trade-offs, and social justice implications. This synoptic quality makes climate change a frequent choice for Paper 3 extended responses and for Extended Essay research — students should recognise that a strong answer will draw on knowledge from multiple syllabus areas.

The topic is structured around two fundamental questions. First, what are the physical processes driving climate change? Answering this requires understanding the global energy balance, the role of greenhouse gases in regulating temperature, the carbon cycle”s operation at planetary scale, and the feedback mechanisms (ice-albedo, permafrost thaw, cloud feedbacks, water vapour feedback) that can amplify or dampen warming trends. These feedback loops are particularly important in extended responses because they demonstrate the complexity of the climate system and the potential for non-linear outcomes.

Second, how do human societies respond to the challenges climate change creates? This second question encompasses mitigation strategies (reducing emissions through renewable energy transition, carbon capture and storage, afforestation, carbon trading), adaptation strategies (coastal defences, drought-resistant agriculture, early warning systems, managed retreat), and the governance frameworks (Paris Agreement, nationally determined contributions, COP decisions) that coordinate action at global and national scales. Students must be able to evaluate the effectiveness of specific strategies using case study evidence — generic descriptions without locational detail will not reach the higher mark bands.

The concept of vulnerability and resilience provides the analytical framework for this topic. Vulnerability is not determined solely by physical exposure to climate hazards — it is mediated by economic resources, institutional capacity, and social networks. Bangladesh, for instance, has high physical exposure to cyclones and sea-level rise but has invested significantly in early warning systems, cyclone shelters, and community-based adaptation, reducing cyclone mortality by over 90% since the 1970s. This demonstrates that vulnerability can be reduced even when physical exposure remains high — a distinction that should be explicit in exam responses.

Climate justice is a recurring thread throughout this topic. The countries and communities that have contributed least to cumulative greenhouse gas emissions (Small Island Developing States such as Tuvalu and Kiribati, least-developed countries, sub-Saharan Africa) face the most severe consequences and have the least capacity to adapt. This asymmetry is relevant to debates about climate finance, loss and damage mechanisms, and differentiated responsibilities under the Paris Agreement — all of which are assessable in exam responses and are suitable topics for the Extended Essay.

Key Concepts

  • Enhanced greenhouse effect — the intensification of the natural greenhouse effect by anthropogenic emissions of greenhouse gases (CO2, CH4, N2O), leading to an increase in global mean surface temperature.
  • Global energy balance — the balance between incoming solar radiation and outgoing terrestrial radiation. Albedo, cloud cover, and atmospheric composition all influence the energy balance.
  • Carbon cycle — the movement of carbon between the atmosphere, biosphere, hydrosphere, and lithosphere through processes such as photosynthesis, respiration, combustion, and weathering.
  • Carbon sequestration — the capture and long-term storage of atmospheric CO2 in natural sinks (forests, oceans, soils) or through engineered techniques (CCS, BECCS, afforestation).
  • Vulnerability and resilience — vulnerability is the degree to which a system is susceptible to harm from climate change; resilience is the capacity to recover. Both are influenced by economic development, governance, and geographic location.
  • Climate justice — the recognition that the impacts of climate change and the costs of mitigation are unevenly distributed, disproportionately affecting low-income countries and communities that contributed least to emissions.
  • Climate feedback loops — self-reinforcing mechanisms that amplify (positive feedback) or dampen (negative feedback) warming. Ice-albedo feedback, permafrost thaw releasing methane, and water vapour feedback are positive; increased cloud cover in some regions provides negative feedback.
  • Nationally determined contributions (NDCs) — the pledges each country submits under the Paris Agreement, specifying its planned emissions reductions and adaptation measures. NDCs are reviewed and updated every five years through a “ratchet mechanism” intended to increase ambition over time.
  • Loss and damage — the adverse effects of climate change that go beyond what can be adapted to, including irreversible impacts such as species extinction, permanent land loss due to sea-level rise, and cultural destruction. The Loss and Damage Fund established at COP28 (2023) is a key mechanism for addressing this.
  • Carbon budget — the maximum cumulative amount of CO2 emissions that can be released while still limiting global warming to a specific target (e.g., 1.5 degrees C or 2.0 degrees C). Staying within the budget requires rapid emissions reductions; exceeding it commits the planet to overshoot and reliance on unproven negative emissions technologies.

Exam Focus

Paper 2 questions on climate change in most cases require:

  • Explaining the causes of climate change with reference to atmospheric processes and human activity.
  • Evaluating the effectiveness of mitigation and adaptation strategies using specific case studies (e.g., carbon trading in the EU, coastal management in Bangladesh).
  • Analysing climate data presented in graphs, maps, or tables.
  • Discussing how vulnerability and resilience vary between countries at different levels of development.
  • Assessing the role of international agreements (e.g., Paris Agreement, Kyoto Protocol) in addressing climate change.
  • Evaluating the concept of vulnerability and resilience, distinguishing between physical exposure and adaptive capacity using contrasting case studies (e.g., Bangladesh vs. the Netherlands).
  • Analysing how climate feedback loops (ice-albedo, permafrost thaw, water vapour) complicate predictions of future warming and policy responses.
  • Discussing climate justice arguments, including differentiated responsibilities under the Paris Agreement and the role of climate finance and loss and damage mechanisms.
  • Applying geographic skills to climate data: interpreting temperature anomaly graphs, atmospheric CO2 concentration records, and climate projection maps for Paper 3.

Worked Examples

Example 1: Evaluating Mitigation Strategies

Problem: Evaluate the effectiveness of carbon trading as a mitigation strategy for climate change. Solution: Carbon trading (e.g., the EU Emissions Trading System) sets a cap on emissions and allows companies to buy and sell allowances. Strengths: creates a financial incentive to reduce emissions; market-based approach is cost-efficient. Limitations: price volatility can undermine investment signals; carbon leakage (companies relocating to regions with laxer regulation) reduces net impact; monitoring and verification are difficult in some sectors. Case study evidence from the EU ETS shows emissions reductions in the power sector but limited impact in heavy industry.

Example 2: Analysing Climate Vulnerability

Problem: Explain why Small Island Developing States (SIDS) are particularly vulnerable to climate change. Solution: SIDS (e.g., Tuvalu, Maldives) face compound vulnerability: low elevation makes them susceptible to sea-level rise and storm surges; limited economic diversification reduces adaptive capacity; small population means limited human capital for adaptation; dependence on imported goods increases exposure to global supply chain disruption. These factors combine physical exposure with economic and institutional limitations, illustrating how vulnerability is multidimensional. The situation of Tuvalu exemplifies this: at an average elevation of less than 2 metres above sea level, even modest sea-level rise threatens freshwater aquifers through saltwater intrusion, destroys coastal agriculture (taro patches), and forces consideration of planned relocation — a scenario that raises profound questions about national sovereignty and cultural continuity. Similarly, the Maldives has invested in artificial island construction (Hulhumale) and floating architecture as adaptation measures, but these are expensive and cannot fully substitute for the natural land being lost.

Common Pitfalls

  • Confusing mitigation and adaptation: Mitigation reduces the causes of climate change (e.g., reducing emissions); adaptation reduces the impacts (e.g., building flood defences). Be precise about which is being discussed.
  • Overgeneralising climate impacts: Impacts vary significantly by region. Use specific case studies (e.g., Bangladesh for flooding, Sahel for desertification) rather than making blanket statements.
  • Ignoring feedback loops: The ice-albedo feedback (melting ice reduces surface reflectivity, accelerating warming) and permafrost thaw (releasing methane) are critical amplifying mechanisms that should be referenced in extended answers.

Summary

Climate change in IB Geography examines the enhanced greenhouse effect, the carbon cycle, and the causes and consequences of global warming at multiple scales. Students must evaluate mitigation strategies (carbon trading, renewable energy transition, afforestation) and adaptation strategies (coastal management, drought-resistant crops) using case studies from contrasting locations. Vulnerability and resilience are influenced by economic development, governance, and geographic location.