Weather and Climate Flashcards
Air Mass
A very large body of air with relatively uniform temperature and moisture characteristics
Air Pressure
The weight of the air above a reference point, measured in millibars
Anticyclone
An area of high air pressure bringing clear skies
Atmosphere
The layer of air round the earth
Climate
The average weather over many years
Condensation
Gas becoming liquid
Convectional rainfall
Rain formed by the sun heating the land surface causing moist air to rise, condense and produce heavy rainfall
Depression
A cyclonic weather system bringing precipitation and winds
Drought
A prolonged period of below average precipitation
Evaporation
Liquid turning to gas
Fog
Cloud at ground level (reducing visibility to 1km)
Front
The boundary between warm and cool air masses
Frontal rainfall
Rain formed when warm, moist air rises over cold air, causing condensation and precipitation
Humidity
The moisture in the air
Isotherm
A line on a map joining points of equal temperature
Jet Stream
A fast-flowing, narrow air current found in the atmosphere
Microclimate
The local climate of a small area
North Atlantic Drift
An ocean current which warms coastal areas in western Europe
Precipitation
Rain, snow, hail, or sleet
Prevailing wind
The most common direction of wind (SW in the British Isles)
Relief rainfall
Rain formed when moist air is forced to rise over highland, causing cooling, condensation and precipitation
What is the difference between weather and climate?
Weather - short term (day to day) variation in weather
Climate - general weather patterns over many years
Examples of extreme weather events
Droughts, wildfires, and hurricanes
When do droughts occur?
When there is abnormally low rainfall for an extended period of time
What are the six main climate zones?
- Polar/sub-polar
- Temperate
- Arid
- Mountainous
- Tropical
- Mediterranean
What are the factors affecting temperature?
Latitude
Altitude
Distance from the Sea
Ocean Currents
Prevailing Wind
What is latitude?
How north or south a location is from the equator
What is altitude?
The height of an object or location above a fixed reference point, such as sea level
What is distance from the sea?
The land warms up and cools down more quickly than the sea; places further inland become hotter in summer and colder in winter.
What is ocean currents?
Continuous movements of seawater in a specific direction
What is prevailing wind?
The most common direction from which the wind blows
What can cause microclimates?
Both natural and human factors.
What are the factors affecting a microclimate?
Physical features
Aspect
Buildings
Surface
Shelter
What is physical features?
Trees, lakes, rivers, hills
What are buildings?
They offer shelter, but can funnel winds, give off heat and make shadows
What is aspect?
Direction in which a place is facing in relation to the sun
What is surface?
It influences air temperature - artificial surfaces warm up faster than natural ones
What is shelter?
Buildings, natural features provide shelter and reduce wind, making it feel warmer
What are the three main types of rainfall?
Relief, convectional, and frontal rainfall
What is relief rainfall?
What is convectional rainfall?
What is frontal rainfall?
