What is Stevenson screen used for?
Stevenson screens may also be known as a cotton region shelter, an instrument shelter, a thermometer shelter, a thermoscreen, or a thermometer screen. Its purpose is to provide a standardised environment in which to measure temperature, humidity, dewpoint, and atmospheric pressure.
Why is a Stevenson screen elevated?
Stevenson screen is used for providing shelter for meteorological instruments, particularly wet and dry bulb thermometers. It is kept 1.25 meters above the ground by legs. It is done so to avoid strong temperature gradients at ground level.
Where do we find a Stevenson screen?
The Stevenson screen is a prominent feature in most weather stations. As we have seen, a weather station is a place where weather or meteorological instruments are kept and used for measuring and recording all the elements of weather. A weather station is normally found in an open area away from any obstructions.
How many thermometers does a Stevenson screen have?
4 thermometers
All 4 thermometers are mounted inside the Stevenson screen to protect them.
Who discovered the Stevenson screen?
engineer Thomas Stevenson
The screen was invented by the Scottish civil engineer Thomas Stevenson (1818–87), the father of Robert Louis Stevenson, the author.
Why Stevenson screen is painted white?
Stevenson screens are always painted white to better reflect the sun’s rays. The louvered sides allow outside air to flow around the thermometers. At some locations, the airflow is assisted by a psychrometer motor that pumps outside air across the instruments inside.
What’s inside a Stevenson screen?
A barometer can be found in a Stevenson screen. This instrument measures air presure. A maximum and minimum thermometer can also be found in a Stevenson screen. They measure highest and lowest temperatures.
What is inside a Stevenson screen?
The Stevenson screen holds instruments that may include thermometers, a hygrometer, a psychrometer, a dewcell, a barometer and a thermograph. Stevenson screens may also be known as a cotton region shelter, an instrument shelter, a thermometer shelter, a thermoscreen or a thermometer screen.
Why is the Stevenson screen on legs?
It is kept 1.25m/4.1ft (UK standard) above the ground by legs to avoid strong temperature gradients at ground level, has louvred sides to encourage the free passage of air, and is painted white to reflect heat radiation, since what is measured is the temperature of the air in the shade, not of the sunshine.
Who designed Stevenson’s screen?
The screen was invented by the Scottish civil engineer Thomas Stevenson (1818–87, the father of Robert Louis Stevenson, the author). It came into use in the late 1860s.