Scientists figure out when next ice age will happen — except humans likely changed everything

Scientists have long known that Earth ’s periodic ice ages follow astronomical patterns first proposed by Serbian mathematician Milutin Milankovitch in the early 20th century .

But the exact mechanisms behind these cycles remained mysterious until now.

The study found that each of three astronomical cycles plays a distinct role in this climate dance.

Future climate can be forecast based on orbital mechanics alone.

Earth ’s climate has followed a roughly 100,000-year cycle for the past million years .

The researchers found that eccentricity matters not because of its direct warming effect, but because it modulates the strength of precession.

During periods of low eccentricity, precession's influence weakens, allowing ice sheets to grow larger without triggering early collapse.

By understanding these natural cycles, scientists gain crucial context for evaluating how human activities are reshaping the climate.

This framework resolves several long-standing puzzles in paleoclimatology, including the “ 100,000-year problem’s.

By demonstrating that glacial inception depends primarily on obliquity, the study suggests that if not for anthropogenic CO , Earth would likely enter another glacial period within 10,000 years .