| Topic: | Re:Re:Re:Re:Flood alerts issued as Thames rises due to 'spring tides' | |
| Posted by: | Tom Pike | |
| Date/Time: | 29/06/21 09:47:00 |
| It’s a balance of both gravitational and rotational forces. Gravity would just cause a single high tide at the point nearest the Moon, with low tide on the opposite side. The balance produces bulges on both sides of the Earth that then rotate with the daily cycle of the Earth, plus about 1/28 of a day as the Moon is slowly circulating around us. That gives a high tide every 12 hours and 25 minutes. The tidal motion of the ocean requires energy, and that is slowly reducing the rotation of the Earth. This energy loss is also why we see only one face of the Moon. There were solid tides on the smaller Moon but they reduced the rotational energy so that it is now tidally locked to the Earth, with a stationary bulge at the nearest point to us and another on its far side. |