Well, blow me down

15 FAST FACTS ABOUT THE WIND..

1 Wind is caused by uneven heating of the Earth’s surface by the sun, creating different atmospheric pressures. Air moves from places with high pressure to those with low pressure.

2 Its speed is measured in knots, or nautical miles per hour, because of their origin in maritime history. One knot is equivalent to 1.15 standard miles. Wind speed is measured using a device called an anemometer.

3 In 1805, Royal Navy officer Francis Beaufort, inset below, came up with the 12-force Beaufort Scale. He devised it while serving on a frigate, HMS Woolwich, by observing the effect of wind on the sails.

4 Sustained wind up to 31mph is officially a breeze, between 32 and 63mph it’s a gale, and above 73mph, it’s a hurricane.