QA

Question: How To Build A Stevenson Screen

What are Stevenson screens made of?

Composition. The traditional Stevenson screen is a box shape, constructed of wood, in a double-louvered design. However, it is possible to construct a screen using other materials and shapes, such as a pyramid.

Why is the Stevenson screen made of wood and not metal?

This is basically a box with louvered sides, often made of wood, so air can flow through, painted white to reflect sunlight – characteristics intended to make the conditions inside the box as near to the outside conditions as practical while simultaneously protecting instruments from precipitation and condensation.

Why is Stevenson screen painted white?

These white louvered boxes can be found at every observing site. Stevenson screens are always painted white to better reflect the sun’s rays. The louvered sides allow outside air to flow around the thermometers.

How do you build an outdoor weather station?

Procedure Have an adult punch a hole in the side of the bottle about an inch from the bottom. Cut the tips off the shoestring. Cut a small piece of packing tape. Push the shoelace through the hole. Wait five to 10 minutes, and read both thermometers. Keep a record of the daily humidity for a few weeks.

Is a rain gauge kept in a Stevenson screen?

The Weather station A major structure in a weather station is a Stevenson screen. The other instruments in a weather station include a rain gauge, wind vane, anemometer, evaporimeter, windsock, sunshine recorder etc.

Why does a Stevenson screen have a double roof?

Stevenson screen has a double roof to reduce excessive heat from solar irradiation.

Why is Stevenson screen raised above the ground?

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.

Why is a hygrometer kept in a Stevenson screen?

Photo: This traditional weather station contains a hygrometer and other weather forecasting equipment. The white louvered box, called a Stevenson screen, protects the instruments from the direct heat of the Sun but allows air to circulate inside, so giving more reliable measurements.

Who invented Stevenson 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.

Which gauging instrument is housed in the Stevenson screens?

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 the use of maximum thermometer?

maximum thermometer A thermometer that records the highest temperature to which it has been exposed (e.g. by allowing a rise of mercury past a restriction in the tube, but preventing the mercury’s return on contraction). It is most commonly used to record maximum daily temperatures.

Which location is best suitable for a Stevenson screen?

The ideal location is one where the distance from any object is 2.5 to 3 x the height of the nearest tree or building. This means that the trees or buildings will not act as a shield, making the measurements unrepresentative. This is the same for the Stevenson screen and the rain gauge.

How is a Stevenson screen useful at a weather station?

Stevenson screen This is a wooden box in which delicate weather instruments at a weather station are kept. Its importance is to protect delicate weather instruments from damage. It is painted to reflect sun heat. It is lowered to allow air circulation within it.

Why should instrument shelter be painted white?

Whatever paint you use, be sure to keep your shelter painted white to prevent excess heat absorption by the wood. Fading paint exposes the wood frame, allowing heat radiation to be absorbed into the shelter unit & causing temperature readings inside the box to be higher than what is actual ambient air temperature.

How do you maintain a Stevenson screen?

Just remove the thermometer set from the Stevenson Screen and run the entire unit under a stream of fresh, cool water for several minutes. This will help dissolve the salt spray and keep corrosion under control. Dry the unit off with a clean cloth and replace back in the screen.

Why Stevenson screen is kept at a height of 1.5 m above the surrounding area?

Explanation: I believe it is to have a standardised hight at which to make weather observations. The temperature at ground level is often much lower in the morning, and higher in the afternoon. There is a specific “liquid in glass” (alcohol usually) terrestrial thermometer for measuring ground temperature.

How do you make a hygrometer?

To make a hair hygrometer you will need 2-3 pieces of hair at least 12 inches long, a 9 inch by 4 inch wooden block or piece of cardboard, two pins or nails, rubbing alcohol, a dime, tape, a marker, a sheet of plastic transparency, a ruler, scissors, and a hair dryer.

Where should a home hygrometer be placed?

Locate your hygrometer in a living area away from the moisture produced by the kitchen or a bathroom. For maximum heating effectiveness and comfort, humidity levels should be between 30% and 50%.

Where is the barometer kept at the weather station?

Most weather stations house their barometric pressure sensor within the weather station display console. Therefore, placement of the weather station console receiver is an important consideration since the physical environment of the console will influence air pressure measurement readings.

What is a Stevenson screen and how does it work?

A Stevenson screen (also known as an instrument shelter) is a meteorological screen to shield instruments against precipitation and direct heat radiation from outside sources, while still allowing air to circulate freely around them.

Which liquid is used in a thermometer?

In a mercury thermometer, a glass tube is filled with mercury and a standard temperature scale is marked on the tube. With changes in temperature, the mercury expands and contracts, and the temperature can be read from the scale. Mercury thermometers can be used to determine body, liquid, and vapor temperature.

What is rain gauge?

Rain Gauge is a meteorological instrument that is used by meteorologists and hydrologists to measure the rain precipitation in a given amount of time per unit area. It is also known by the names of udometer, pluviometer, and ombrometer.