Houston has an hour more of sunlight than Chicago, but in summer, they get fewer sunlight hours. Do the possible sunlight hours average out over the year?

Weather Blog

Dear Tom,

We spent Thanksgiving in Houston this year, and they have an hour more of sunlight than Chicago, but in summer, they get fewer sunlight hours. Do the possible sunlight hours average out over the year?

Thanks, Paul Geddes, Rockford

Dear Paul,

They do. With minor differences in polar regions, areas on this planet receive the same amount of sunshine (disregarding cloudiness) annually. The complication is that, because the Earth’s axis of rotation is tilted 23.45 degrees from the plane described by its revolution around the sun, the daily hours of light, planetwide, are distributed unequally through the year. At the poles, daylight comes in six-month blocks. At the equator, it is always within a few minutes of 12 hours a day. Residents of far northern latitudes are often dismayed to find a much earlier onset of darkness when they travel south in the summer.

Copyright 2022 Nexstar Media Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.


Latest News

More News