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8. How Can We Measure The Weather?
L/O: To know and understand the name of a range of instruments and what they are used for

9. Weather is...
the day to day condition of the air around us over a short period of time.

10. Why do people measure the weather?
To plan ahead – decide when to do certain things
To plan holidays at the right time of year
To decide what to wear
To prepare for bad weather e.g. flooding or heavy snow
For people’s jobs e.g. people who pilot planes and ships, farmers and mountaineers

11. Temperature Temperature means how hot or cold it is
It is usually measured with a thermometer in degrees centigrade(ºC)

12. Pressure Pressure is a measure of how heavy the air is.
Pressure is measured with a barometer in millibars (mb)

13. Cloud Cover
Cloud Cover tells us how much of the sky is covered by clouds.
It is measured by estimating the amount of cloud cover in eighths.

15. Wind Speed Wind speed is how fast the wind is blowing.
An anemometer measures wind speed in mph or on the Beaufort wind scale from 1-12.
The most common type looks like a toy windmill. Three cups are fixed to a central shaft and the stronger the wind blows the faster they spin around. The wind speed is shown on a dial, just like a car's speedometer.

16. Wind Direction Wind direction is where the wind is blowing from.
Wind Vane/Wind Sock: measures wind direction by pointing towards North, East, South or West

17. Rainfall/Precipitation
Precipitation is water falling from the sky.
Rain gauge: measures the amount of rainfall in mm. Not only does a rain gauge measure rainfall, but also all other forms of precipitation.

18. Sunshine Sunshine is light and warmth from the sun.
A Campbell Stokes Recorder measures sunshine.
This type of recorder is made up of a glass ball which concentrates sunshine on to a thick piece of card. The sunshine then burns a mark on the card which shows the number of hours of sunshine in the day.

19. Visibility Visibility is how far ahead we can see.
It is measured using a tape measure or trundle wheel, in metres or kilometres.

20. Weather Term
Means….
Usually given….
Measured using….
Temperature
Exactly how hot or cold it is.
In Celsius or Fahrenheit
Thermometer
Air pressure
How heavy the air is.
In millibars (mb)
Barometer
Cloud cover
How much of the sky is hidden by clouds.
In Oktas (eighths)
Your eyes.
Wind speed
How fast the wind is blowing.
In MPH (like a car) or with the beaufort wind scale from 1-12
Anemometer
Wind direction
Where the wind is blowing from (a south-west wind blows FROM the south-west)
As a compass point (N, NW, SW and so on)
Weather vane
Precipitation
Water falling from the sky in any form (precipitation)
In millimetres or Inches
Rain gauge
Visibility
How far ahead we can see, for example on a foggy day.
In metres or kilometres.
Visibility meter

21. What do you know?