- regions of Earth classified by temperature and precipitation patterns
- five major zones: tropical, subtropical, temperate, continental, polar
- tropical: warm year-round, high rainfall, supports tropical rainforest and savanna
- subtropical: warm with dry summers or humid conditions, Mediterranean and monsoon climates
- temperate: moderate temperatures, four seasons, deciduous and mixed forests
- continental: extreme seasonal variation, hot summers, cold winters, interior of continents
- polar: permanently cold, minimal precipitation, supports tundra and ice sheet biomes
- determined by latitude, altitude, ocean currents, and proximity to water bodies
- Koppen classification system is the standard scheme using temperature and precipitation thresholds
- atmosphere circulation (Hadley, Ferrel, Polar cells) drives zone boundaries
- shifting poleward due to climate change, altering biome distribution and agriculture
- deserts occur where descending air creates persistent high pressure (subtropical ridge)