Sunshine, Humidity & Air Pressure
Geography: KS3, topic 5.1.4
Sunshine, Humidity and Air Pressure
As well as temperature, precipitation, cloud cover and wind, meteorologists also measure sunshine, humidity and air pressure.
Sunshine
- Sunshine is measured in the numbers of hours of sunshine per day, month or year.
- Holidaymakers, event planners and farmers always want sunshine!
Sunshine records in Britain
- Chichester in Sussex was named the sunniest city in the UK in April 2018.
- Chichester usually has more than 1,900 hours of sunshine per year.
- Glasgow in Scotland is one of the dullest cities in Europe with less than 1,203 hours of sunshine in some years.
Humidity
- Humidity is the amount of water vapour as a gas in the atmosphere.
- Humidity is usually invisible to the human eye.
- The most humid cities on Earth are generally located on the coast and close to the equator.
Air pressure
- Air pressure is the weight of air pushing down on the surface of the Earth at one location.
- Air weighs very little.
- The Earth's atmosphere continues for many kilometres above the ground.
- There is so much air that it creates enough weight for us to be able to measure it.
Measuring air pressure
- Air pressure is measured with a barometer in Pascals or millibars.
- Older measurements include:
- Inches of mercury
- Pounds per square inch
High and low pressure
- Weather forecasters often talk about high or low pressure.
- High pressure usually gives fine settled weather.
- Low-pressure systems often bring rain and storms.
Test yourself on Sunshine, Humidity & Air Pressure
Which city was named the sunniest city in the UK in April 2018?
What is used to measure air pressure?