Our Atmosphere Flashcards
What does temperature mean
Exactly how hot or cold it is
What is temperature usually given in
Degrees centigrade (‘C)
What is temperature measured with
Thermometer
What equipment is needed to measure the temperature
Thermometer
What does air pressure mean
How ‘heavy’ the air is
What is air pressure usually given in
Millibars (mb)
What is air pressure measured using
Barometer
What equipment is needed to measure air pressure
Barometer
What does visibility mean
How much of the sky is hidden by clouds
What is visibility usually given in
Oktas
What is visibility measured using
Your eyes; satellite image
What equipment is needed to measure visibility
A beam of light is sent out and a sensor measures how much arrives
What does wind speed mean
How fast the wind is blowing
What is wind speed usually given in
Kilometres (MPH)
What is wind speed measured using
Anemometer
What equipment is needed to measure wind speed
Anemometer, the wind turns the cups which turn a counter
What is weather direction
Where the wind is blowing from
What is weather direction usually given in
North
South
East
West
What is weather direction measured using
Wind vane
What equipment is needed to measure weather direction
Wind vane
What does precipitation mean
Water falling from the sky in any form
What is precipitation usually given in
Millilitres
What is precipitation measured using
Rain gauge
What equipment is precipitation measured using
Rain gauge
What is weather
Weather is the state of the atmosphere over a short period of time
Give a cloud type (1)
Cumulus - these are puffy clouds that sometimes look like pieces of floating cotton. The base of each cloud is often flat and may only be 1000m (3300ft) above the ground
Give a cloud type (2)
Stratus - are uniform clouds (greyish) that often cover the entire sky. They resemble fog that does not reach the ground. Usually no prescription falls from stratus clouds, but sometimes they drizzle
Give a cloud type (3)
Cirrus - the most common form of high level clouds are thin, often wispy cirrus clouds. Typically found at heights greater than 20,000 feet (6,000 metres), cirrus clouds are composed of ice crystals that originate from the freezing of super cooled water droplets
Give 1 word describing cumulus
Fluffy
Give 1 word describing cirrus clouds
Icy
Give 1 word describing nimbo clouds
Rainy
Give 1 word describing stratus clouds
Layered
Give 1 word describing alto clouds
Middle
Describe Convectional Rainfall
Here the air rises because the ground heats it. It rises n warm currents. We call these convection currents. So we call the rain Convectional rainfall. In the UK we get Convectional rainfall island in summer, where the ground gets hottest far from the cooling effects of the sea
Describe Relief Rainfall
Wind is moving air. When the wind meets a line of high hills or mountains there’s only 1 way to go, up. So the air rises and cools, and we call this Relief rainfall. In the UK the prevailing wind is from the South West. So we get Relief rainfall on the high land along the West Coast
Describe Frontal Rainfall
Huge blocks of air called air mases move around the earth. When a warm air mass meets a cold one the warm is forced to rise. So we get rain. This is called Frontal rainfall. Frontal rain can fall anywhere, since masses can travel in anywhere. But in the UK, they often arrive in the Atlantic Ocean. So the west of the UK gets a lot of Frontal rain.
What is air pressure
Although we can’t feel it, all the air above us is pressing down on us, giving sir pressure. If air pressure is low, it means air is rising. If it is high, it means air is sinking. If it is low, it means air is rising. Each brings different weather.
A fall in air pressure is a sign of what weather
Rain and wind
If the air pressure is low what will the weather be
Bad
High air pressure means no clouds. Which means what about weather in winter and in summer
It gives us our hottest summer and coldest winter weather
What is a depression
Depressions are low systems which developed when warm or cold air masses meet. They are the most common weather system affecting the British Isles bringing rain, cloud and increased wind speeds.
