Sussex Police are to deploy more officers when there is a full moon after a study of crime figures that linked violent behaviour to the phases of the Moon (The Times, June 6).

This is a controversial area, though – and so, too, is the idea that the Moon can affect the weather. However, a study in the US has revealed an unexpected 18-year pattern of rainfall in the Midwest. This matched a lunar cycle as the Moon orbits the Earth, and seemed to affect winds sweeping down from the Rocky Mountains, which helped to create drought or rain.

Elsewhere, the full moon has been linked to slightly fewer bouts of heavy rainfall in Sydney, and also during the monsoons in Jakarta and in Mangalore on the west coast of India.

There also appears to be a link between the Moon and the daily range of temperature. A survey of weather records has revealed that the daily range rises slightly towards full moon, and falls to its lowest at new moon, a difference of up to 0.3C (0.5F).

One explanation is that moonlight can warm the Earth slightly at full moon, although only at night, of course. But the position of the Earth and Moon in the solar system is also important. At full moon, the Earth moves slightly closer to the Sun than at new moon, receiving a touch more solar radiation during the day and raising maximum temperatures.