CBC British Columbia
Questions for Claire
Story Tools: EMAIL | PRINT | Text Size: S M L XL | REPORT TYPO | SEND YOUR FEEDBACK | Bookmark and Share

As the earth spins one rotation per day, does it spin the weather patterns? For example does England eventually get our "weather" and do we get China's?

Question submitted by David Mallory
(Vancouver, BC)

David,
Fantastic question! But I have to go back to basics to explain this:
Weather is created due to the day by unequal heating of the atmosphere, and the motion of the earth spin, drags the atmosphere around with it, with the overall result being a combination of global patterns of wind which follow a regular yearly cycle.

Wind and weather are created by the action of the Sun, heating up different parts of the land and sea by varying amounts. For example, the sun is overhead in the tropics, therefore it has less atmosphere to pass through so the effects of heat are greater. Warm air rises and cooler air flows alongside, replacing the displaced air resulting in large scale air movement or wind as we know it.

The rotation of the earth means that it is a spinning globe where at one point of the equator is traveling at 1100 km/hour, whilst a point at the poles is not affected by rotation. This results in what is known as Coriolis forces which act to cause an apparent deflection of a motion. This can be explained in terms of an imaginary force that can be translated into terms of gravitational pressures.

Due to the effects of the Sun and the effect of varying degree of heat on certain areas such as the equator and the Poles, resulting in surface winds or air moving towards the equator at the surface and towards the Poles at altitude. "At mid-latitudes we can see that air moves towards the Poles via the surface and moves to the Equator at altitude".

The effects of wind force and direction dictates to some extent to the type of weather we are going to experience, and how that weather will affect people "along the way".


« Previous Post | Main | Next Post »