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Glossary & sources
Every tricky term used across this site, explained simply — plus where the numbers and facts actually came from.
Terms explained0
- Adaptation
- Changing how we live or build to cope with a climate that's already shifting — like raising buildings above flood level.
- Albedo
- How much sunlight a surface reflects rather than absorbs. Fresh snow has high albedo (reflects a lot); dark ocean water has low albedo (absorbs a lot).
- Biodegradable
- Material that natural processes can break down over time, like food waste or paper — unlike most plastics.
- Carbon footprint
- The total greenhouse gases a person, product or activity is responsible for, usually measured in tonnes of CO2-equivalent per year.
- Carbon sequestration
- Capturing and storing carbon so it doesn't stay in the atmosphere — trees and soil do this naturally; some technologies try to do it artificially.
- Climate
- The long-term, averaged pattern of weather in a place, typically measured over 30 years.
- Climate justice
- The idea that the people and countries who've contributed least to climate change often suffer its worst effects — and that responses should account for that imbalance.
- Deforestation
- Clearing forest land, which removes a major carbon-absorbing resource and often releases stored carbon back into the air.
- El Niño / La Niña
- Natural, multi-year ocean-temperature cycles in the Pacific that shift weather patterns worldwide — separate from, but layered on top of, long-term global warming.
- Emissions
- Greenhouse gases released into the atmosphere, usually from burning fuel, farming, or industrial processes.
- Fossil fuel
- Coal, oil and natural gas — formed from ancient organic matter over millions of years, and the largest source of human-caused emissions when burned.
- Greenhouse effect
- The natural process by which certain gases trap heat in Earth's atmosphere, keeping the planet warm enough to support life.
- Greenhouse gas
- Any gas that traps heat in the atmosphere — mainly carbon dioxide (CO2), methane, nitrous oxide and water vapour.
- IPCC
- The Intergovernmental Panel on Climate Change — the United Nations body that reviews and summarises the global scientific research on climate change.
- Methane
- A greenhouse gas released by livestock, rice farming, landfills and gas leaks — far more potent than CO2 per molecule, though it breaks down faster.
- Mitigation
- Action taken to reduce or prevent greenhouse gas emissions in the first place, as opposed to adapting to effects that are already happening.
- Net zero
- A state where any remaining greenhouse gas emissions are balanced out by removals — through forests, technology, or other means — so the net addition to the atmosphere is zero.
- Ocean acidification
- Oceans absorbing extra CO2 from the air, which makes seawater more acidic and stresses coral reefs and shellfish.
- Paris Agreement
- A 2015 international agreement where countries committed to limit global warming, broadly to well below 2°C above pre-industrial levels.
- ppm (parts per million)
- A way of measuring tiny concentrations — 427 ppm of CO2 means 427 out of every one million air molecules are CO2.
- Pre-industrial baseline
- Conditions before large-scale fossil fuel use began (roughly 1850–1900), used as the comparison point for how much warming has happened since.
- Renewable energy
- Energy from sources that naturally replenish, like sunlight, wind, and flowing water, instead of being extracted and burned.
- Sea level rise
- The long-term increase in ocean height caused by melting ice and seawater expanding as it warms.
- Weather
- What's happening in the atmosphere right now or over the next few days — distinct from the long-term pattern that defines climate.