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FrançaisLearning Objectives
- Explain the greenhouse effect and identify the major greenhouse gases by source and warming potential.
- Read a country's annual emissions profile (total, per capita, per unit GDP) and explain what each measure tells you.
- Distinguish between mitigation (reducing emissions) and adaptation (preparing for impacts).
- Describe the structure of the Paris Agreement and what a "Nationally Determined Contribution" commits a country to.
- Evaluate a country's climate vulnerability using exposure, sensitivity, and adaptive-capacity criteria.
Key Concepts
Earth's climate is warming faster than at any point in the last 10,000 years. The scientific consensus, codified by the IPCC, is that human activity — primarily burning fossil fuels — is the cause. The mechanism is the greenhouse effect: gases like carbon dioxide, methane, and nitrous oxide trap heat in the atmosphere that would otherwise escape to space. Pre-industrial atmospheric CO2 sat around 280 parts per million; today it exceeds 420 ppm.
Countries contribute to and are affected by climate change very unevenly. Annual emissions are dominated by China (roughly 30 percent of global CO2), the United States (about 14 percent), and India (about 7 percent), but cumulative historical emissions weigh much more heavily on early industrializers: the United States and European nations together account for roughly half of all CO2 released since 1850. Per capita emissions look different again: the US and Australia lead large economies, while India and most African countries emit a fraction of the global average.
The political response is the Paris Agreement (2015), a framework under the UN Framework Convention on Climate Change. Each participating country submits a voluntary Nationally Determined Contribution (NDC) pledging emissions reductions, updated every five years. The agreement's goal is to keep global warming well below 2 °C above pre-industrial levels, ideally to 1.5 °C. Current NDCs, even if fully implemented, project warming closer to 2.5-3 °C.
Impacts are unequal too. Small island nations face sea-level rise that threatens their existence. Coastal megadeltas (Bangladesh, the Nile, the Mekong) face compound flooding and saltwater intrusion. Sub-Saharan agricultural economies face desertification. Arctic nations face permafrost collapse and coastline erosion. Adaptive capacity — the wealth, institutions, and technology needed to adapt — is also unevenly distributed, and often inversely correlated with responsibility for emissions.
Country Case Studies
China
Largest annual emitterChina emits about 30 percent of the world's CO2 annually but has lower per capita emissions than the US. It leads the world in solar and wind deployment and has pledged to peak emissions before 2030 and reach net-zero by 2060.
Country page
United States
Largest cumulative emitterThe US has emitted more CO2 historically than any other country — roughly 25 percent of cumulative emissions since 1850. It re-entered the Paris Agreement in 2021 and pledges a 50-52 percent cut below 2005 levels by 2030.
Country page
Bangladesh
Highly vulnerable, low emitterOne of the world's most densely populated countries sits on the low-lying Ganges-Brahmaputra delta. Sea-level rise, cyclone intensification, and saltwater intrusion threaten tens of millions. Per-capita emissions are a fraction of the global average.
Country page
Maldives
Existential threatThe average elevation of the Maldives is 1.5 meters above sea level. The government has led a decade-long international campaign on behalf of small island states and is buying land abroad as a contingency against submergence.
Country pageDiscussion Questions
- Compare annual, cumulative, and per-capita emissions. Which metric best captures a country's "responsibility" for climate change, and why does the choice matter politically?
- The Maldives and China both signed the Paris Agreement. How do their situations differ, and what does the same treaty commitment mean for each?
- Is the Paris Agreement's voluntary NDC structure a strength or a weakness? What are the alternatives?
- Bangladesh emits very little per capita but faces some of the worst climate impacts. Do high-emitting countries owe climate reparations? What would that look like?
- Pick one adaptation project (sea walls, drought-resistant crops, managed retreat, air-conditioning access). What does its success depend on, and who pays?
Classroom Activities
Emissions Data Lab
Each student picks one country and pulls its annual, cumulative, and per-capita CO2 emissions from a live data portal. They rank the countries three different ways and discuss what changes.
NDC Comparison
Students work in pairs, each picking one developed and one developing country's NDC. They summarize each country's 2030 and net-zero targets and assess which commitment is more ambitious relative to current emissions.
Vocabulary
Standards Alignment
Draft alignment — pending educator review.