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How can we measure the weather?

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es Which instruments are used to measure the weather?

How can you measure the weather?

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Rainfall

Rain is a type of precipitation.

Precipitation is where water vapour in the air is cooled and condenses into water droplets.

Other types of precipitation are snow, sleet, hail, dew or fog.

rain gauge

Rainfall is measured with a rain gauge.

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Temperature

Thermometer

Temperature can be measured using a thermometer such as the liquid-in-glass type, where the liquid (mercury or spirit) in the bulb expands and rises up a capillary tube. Temperature is measured in either oCelsius or oFahrenheit.Temperatures are measured in the shade, so that the heat of the sun does not heat up the instrument being used.

How is temperature measured?

Temperature is how hot or cold it is.

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Wind

anemometer

Wind speed is measured by an anemometer. This has metal cups which rotate in the wind. The stronger the wind, the faster the anemometer turns.

Wind is simply moving air.

Wind speed is how fast the air is moving.

How is wind speed measured?

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Wind direction

Wind direction is measured using a wind vane.

How is wind direction measured?

the arrow points into the wind

In this case, the wind has come from the north. It is a northerly wind.

See if you can spot a wind vane in your local area.

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Sunlight

Sunlight is the amount of daylight.

How is sunlight measured?

The duration and the intensity of sunlight is measured using a Campbell-Stokes sunshine recorder. These focus light from the sun onto a piece of card where it leaves a burnt trace. The more sunshine there is, the longer the line.

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Air pressure

It is measured with a barometer.

Air pressure is the force exerted on the Earth by the weight of the air above.

How is air pressure measured?

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Weather instruments

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Cloud cover

Cloud cover is the fraction of the sky covered in clouds.

clear sky

Cloud cover can be measured by observation. It is measured in oktas.

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Which instrument?