Theme C: Weather And Climate Flashcards
What is weather?
Weather is the day to day condition of our atmosphere
What is climate?
Climate is the average weather conditions in an area based on the average weather over 30 years or longer
What does a thermometer measure?
Temperature
What units does a thermometer use?
Degrees Celcius/Farenheit
What does a Steevensons Screen store?
Thermometers
What colour is a Steevensons screen and why is it this colour?
White - To reflect sunlight
What measures Precipitation?
Rain Gauge
What units is Precipitation measured in?
Millimetres (mm)
What measures wind direction?
Wind Vane
What units are used to measure Wind direction?
The 8 Points on a compas
What measures Wind Speed?
Anemometer
What unit is wind speed commonly measured in?
Knots
What measures Atmospheric Pressure?
Barometer
What unit is Atomspheric Pressure measured in?
Millibars (mb)
What is cloud cover measured in?
Oktas
What are Stratus clouds like?
Layered clouds, low.
Grey + shapeless
Bring drizzle and rain
What are Cumulus clouds like?
White , fluffy, cotton wool appearance.
Can bring rain and showers - especially when base is grey
What are Cumulonimbus clouds like?
Deeper clouds
Climb high into atmosphere
Often have heavy rain, thunder + lightning storms
What are Cirrus clouds like?
High clouds
Wispy
Made from ice crystals
What sources are used for data for weather forecast?
Weather Buoys
Rainfall Radar
Satellites
Land Based Weather Stations
How does latitude affect climate?
The sun shines directly overhead at the equator, causing its rays to concentrate on a small area which means it heats up a lot. Near the Poles the same amount of sun energy is spread over a larger area, causing it to not heat up as much.
How does Prevailing wind affect climate?
If the prevailing wind comes from a warm place, it will bring warm air. If from a cold place, it will bring cold air. If it comes from over the sea, it’ll pick up water and bring rain. If it comes from over land, it’ll be dry.
How does Altitude affect climate?
As the altitude increases, the air is thinner which makes it very difficult for heat to be transferred between the molecules as they’re further apart.
How does Distance from the sea affect climate?
Places inland heat and cool more quickly than the sea so are colder in winter because the land loses heat and the sea holds its heat longer.
What is tropical maritime air mass and what conditions does it bring ?
Warm and moist air.
Mild conditions in winter, wet weather in summer.
Brings clouds, drizzle & fog
What is tropical continental air mass and what conditions does it bring ?
Warm and dry
Mild conditions in winter
What is Polar Maritime air mass and what conditions does it bring ?
Cold and Moist
Causes rain fail in summer
Creates clouds due to unstable air
What is polar continental air mass and what conditions does it bring ?
Cold and dry
Brings cold conditions in winter
Milder Conditions in summer
Can bring unstable air in winter producing snow, usually brings cool dry conditions
What is an anticyclone?
A weather system of high pressure
In anti cyclone, how does the air move?
It sinks
In an anti cyclone, what is the cloud cover?
0 as clouds can not form
What is the wind direction in an anticyclone?
Clockwise
What is the duration of an Anticyclone?
Long duration as it remains the same for several days, weeks or more
What is a depression?
A weather system of low pressure
What is the air movement in a depression?
It rises
What is the wind speed in an anticyclone?
Gentle, blowing out from centre.
Isobars far apart
What is the cloud cover of a depression?
There is cloud cover as air rises , cools and condenses to form clouds
What is the wind direction of a depression?
Anti clockwise
What is the duration of a depression?
Around 24 hours
Describe the sequence of weather in a depression
Warm front approaches. At front warm air rises over cold air and forms clouds and rainfall.
Warm Sector causes temperatures to rise, heavy rain stops and chance of drizzle.
Cold front arrives. Warm moist air lifted over clouds air, clouds and heavy rain occur.
Cold sector approaches lowering temperature and breaking up clouds causing showers to become fewer.
How is a warm front formed?
When warm tropical maritime air rises over a mass of cold polar maritime air
What is a cold front?
A transition zone where a cold polar maritime air mass is replacing the warmer tropical maritime air mass
What is an occluded front?
The point where a cold front takes over a warm front or vice versa
What do occluded fronts bring?
Changeable weather conditions
