Unit Vocabulary

2. – bacteria temporarily lock up nutrients for their own use
3. – movement of rock layers bringing nutrients back to surface
5. Niño – a periodic warming of surface waters in the central and eastern Pacific Ocean that weakens trade winds and alters global weather patterns.
11. cycle – movement of elements through living organisms and the environment
13. –absorption of nutrients by an organism.
14. – the shape of Earth’s orbit around the Sun, ranging from more circular to more elliptical on ~100,000-year cycles.
15. –tThe fraction of sunlight reflected by a surface; higher albedo means more reflection and less heat absorption.

1. change – a long-term shift in Earth’s average temperature and weather patterns, occurring naturally or through human influence.
4. – the slow wobble of Earth’s axis, changing the timing of the seasons relative to Earth’s position in orbit (~26,000-year cycle)..
6. – conversion of nitrates back to atmospheric N₂ gas
7. Cycles – long-term variations in Earth’s orbit, tilt, and wobble that alter how solar energy is distributed across the planet.
8. – phosphate settles in oceans forming new rocks
9. – bacteria convert ammonia to nitrites (NO₂⁻) and nitrates (NO₃⁻)
10. Tilt (Obliquity) – the angle between Earth’s rotational axis and its orbital plane, varying between 22.1° and 24.5° every ~41,000 years.
12. Niña – the cooling phase of the El Niño–Southern Oscillation (ENSO), when stronger trade winds push warm water westward, increasing upwelling in the eastern Pacific.