Will the seasons change due to precession? (Intermediate)

I read in an article online that in approximately 12,000 years, due to precession, Winter will occur in the Northern Hemisphere during June, July and August. Is this true? What is the relationship between the seasons and the ecliptic?

To answer your question, you first have to understand the relation between the ecliptic and seasons. The ecliptic is the plane in which the Earth orbits the Sun. Due to the tilt of the Earth's axis, the ecliptic is tilted by 23.5 degrees to the equatorial plane. So, at a certain time during the year, the Sun is directly overhead 23.5 degrees north latitude, and 6 months later, it is directly over 23.5 degrees south latitude. These two points correspond to the Summer and Winter Solstice respectively in the Northern hemisphere.

Due to precession, the Earth's axial tilt slowly changes over time. As time progresses, the locations on the Earth's orbit at which equinoxes and solstices occur will change. Thus, the location of the current summer solstice will become the location of winter solstice 13,000 years hence. However, months in a Gregorian calendar year are defined by seasons and so winter in the Northern hemisphere will never occur during June. At any point in future, the Northern hemisphere will experience summer during June and winter during December, but due to precesion, the months will correspond to different positions of the Earth's orbit around the Sun.

 

This page was last updated on Jan 28, 2019.

About the Author

Jagadheep D. Pandian

Jagadheep D. Pandian

Jagadheep built a new receiver for the Arecibo radio telescope that works between 6 and 8 GHz. He studies 6.7 GHz methanol masers in our Galaxy. These masers occur at sites where massive stars are being born. He got his Ph.D from Cornell in January 2007 and was a postdoctoral fellow at the Max Planck Insitute for Radio Astronomy in Germany. After that, he worked atĀ the Institute for Astronomy at the University of Hawaii as the Submillimeter Postdoctoral Fellow. Jagadheep is currently at the IndianĀ Institute of Space Scence and Technology.