Question

Which one of the following weather instruments is kept outside the Stevenson screen?
1. Barometer
2. Anemometer
3. Hydrograph
4. Maximum and minimum thermometers

Answer 1

Correct Answer - Option 2 : Anemometer

Anemometer is kept outside the Stevenson screen.

Stevenson screen:

• The Stevenson screen is designed to protect thermometers from precipitation and direct sunlight while allowing air to circulate freely around them.
• It is made from wood with louvred sides to allow the free and even flow of air. It is painted white to reflect radiation.
• It stands on four legs and is about 3 feet 6 inches above the level of the ground.
• The legs must be sufficiently rigid and be buried sufficiently in the ground to prevent shaking.
• The front panel is hinged at the bottom to form a door, which allows for maintenance and reading of the thermometers.
• The door of the Stevenson screen is always towards the north in the northern hemisphere and towards the south in the southern hemisphere because direct sunrays also affect mercury.
• The purpose of the Stevenson screen is to create a uniform temperature enclosure that closely represents the same temperature as the air outside

Some weather instruments:

Weather instruments	Function
Barometer	The instrument used to measure atmospheric pressure is called a barometer. The most commonly used barometers are mercury barometer, aneroid barometer, and barographs. The unit of measurement is in the millibar.
Anemometer	An anemometer is a device used for measuring wind speed and direction. It is also a common weather station instrument. The term is derived from the Greek word anemos, which means wind, and is used to describe any wind speed instrument used in meteorology.
Hydrograph	A hydrograph is a graph or plot that shows the rate of water flow in relation to time, given a specific point or cross-section.
Maximum and minimum thermometers	The maximum thermometer and minimum thermometer are used to measure the air temperature. A set of these thermometers is kept in the Stevenson Screen The maximum thermometer is designed to record the highest temperature during a day. The minimum thermometer records the lowest reading in a day.