D4.3.2—Positive feedback cycles
Positive feedback cycles accelerate climate change when warming triggers processes that release greenhouse gases or increase solar absorption even further.
- Syllabus
- First assessment 2025
- Objective
- D4.3.2
- Level
- HL
Exam analysis
Chance of appearing3%of analysed past papers
Latest appearanceNovember 2025
Most common paperPaper1
Typical marks1–4
Common command terms
- Identify
- Explain
Recent exam appearances
November 2025Paper1B ["HL"] · TZ34(e)[ 4 ]D4.3.2—Positive feedback cycles
May 2025Paper2 ["HL"] · TZ32(c)[ 1 ]D4.3.2—Positive feedback cycles
May 2014Paper1 ["HL"] · TZ216[ 1 ]D4.3.2—Positive feedback cycles
Practice this objective
Coverage 2014–2025 · Updated 16 Jul 2026
Concept essentials
- Positive feedback reinforces the original warming instead of opposing it.
- Loss of snow and ice lowers albedo and increases solar energy absorption.
- Thawing organic stores can release carbon dioxide or methane that further strengthens warming.