How Much Do Diamond Engagement Rings Cost. There are two major factors which contribute to the cost of a diamond: a ratings system called the âFour Csâ and whether or not the diamond is ASG/GIA certified. The Four Cs refers to the diamondâs color, cut, clarity, and carat size.
Best Answer: A wind vane is used to tell wind direction. The National Weather Service and those that have a lot of money use a Aerovane. Aerovanes are commonly used at many weather stations and airports to measure both wind direction and speed.
Feb 17, 2015. Wind speed is measured in knots (nautical miles per hour) by an instrument called an anemometer. It is made up of a series of cups that catch the wind. The mechanism pulls on a spring which is calibrated to record the speed. Direction is simply observed by use of a vane or wind sock which points in the direction from which the wind is coming.