• Researchers have identified a “tipping point” about 2.7 million years ago when global climate conditions switched from being relatively warm and stable to cold and chaotic, as continental ice sheets expanded in the Northern Hemisphere. • Following this transition, Earth’s climate began swinging back and forth between warm interglacial periods and frigid ice ages, linked to slow, cyclic changes in Earth’s orbit. • However, glacial periods after this tipping point became far more variable, with large swings in temperature over relatively short timescales of roughly a thousand years.
Article Summaries:
- Researchers have pinpointed a climate “tipping point” that occurred about 2.7 million years ago, when Earth’s global conditions shifted from a relatively warm, stable regime to a colder, more chaotic one marked by the expansion of Northern Hemisphere ice sheets. After this transition, the planet began oscillating between warm interglacial periods and frigid ice ages, driven by slow, cyclic changes in Earth’s orbit. However, the glacial periods that followed became far more variable, featuring large temperature swings over relatively short timescales of roughly a thousand years. This heightened climate volatility may have influenced the evolutionary pressures on early hominins.
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