What orbital cycle describes changes in Earth’s axial tilt over roughly 41,000 years?

The obliquity cycle describes changes in Earth’s axial tilt over roughly 41,000 years.

Earth’s axis is not fixed at one angle. Its tilt varies between about 22.1 and 24.5 degrees, changing how strongly the seasons differ and how sunlight is distributed between high and low latitudes. Greater tilt generally produces more extreme seasons, especially near the poles.

The cycle is one of the three Milankovitch cycles, named after Serbian mathematician and astronomer Milutin Milanković. The other two are axial precession, a wobble lasting roughly 26,000 years, and orbital eccentricity, which changes the shape of Earth’s orbit over much longer intervals.

These cycles influence long-term climate patterns, including the timing of ice ages, by altering seasonal and latitudinal sunlight. They do not explain today’s rapid global warming, which is occurring far too quickly and is primarily driven by rising greenhouse-gas concentrations from human activities.