This deep dive covers Evidence for Climate Change within Climate Change for GCSE Chemistry. Revise Climate Change in Atmosphere for GCSE Chemistry with 20 exam-style questions and 15 flashcards. This topic appears less often, but it can still be a useful differentiator on mixed-topic papers. It is section 4 of 17 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 4 of 17
Practice
20 questions
Recall
15 flashcards
🔬 Evidence for Climate Change
1. Temperature Records
- Instrumental records since 1880 show a clear warming trend
- 19 of the 20 warmest years on record occurred after 2000
- Ocean temperatures have increased in all ocean basins
2. Ice Core Data
- Bubbles trapped in ice contain ancient atmosphere samples
- Show CO₂ levels for the past 800,000 years
- Current CO₂ levels are the highest in all of human history
- CO₂ concentration correlates closely with temperature in the ice core record
3. Melting Ice
- Arctic sea ice declining by 13% per decade
- Greenland ice sheet losing ~280 billion tonnes per year
- Mountain glaciers retreating worldwide (photographic evidence over decades)
- Ice loss contributes to sea level rise and reduces the Earth's reflectivity (albedo effect)
4. Sea Level Rise
- Global average rise of 23 cm since 1880
- Rate of rise has accelerated to 3.3 mm per year
- Caused by two mechanisms: thermal expansion of seawater AND ice melt
5. Changing Seasons and Ecosystems
- Earlier spring events (flowering, bird migration, insect emergence)
- Growing seasons extended in many regions
- Species ranges shifting poleward and to higher altitudes