Climate and Weather Flashcards
What are the characteristics of a mid-latitude cyclone?
(8)
Warm front, cold front, warm sector, cold sector, clockwise rotation, low pressure, occlusion, circular isobars
Where are mid-latitude cyclones formed?
Below the equatorial LP, between the subtropical HP and polar LP
Name the conditions of a mid-latitude cyclone
(5)
- Two large high pressure systems
- Subtropical HP
- Polar HP
- The air masses meet at the polar front
- Warm air is forced upwards and cold air flows in
Explain a cold front
Air behind front is cold, air ahead of the cold front is slightly warmer, this causes the warm air in front to be uplifted along the cold front, rising air cools, condensation takes place and forms nimbostratus clouds, this results in rain.
Explain a warm front
Air ahead of the cold front is slightly colder than the air behind the cold front, this results in the air behind the cold front and the warm air in warm sector rising over the cold air in the front, rising air cools, condensation takes place and forms nimbostratus clouds, this results in rain.
What are the stages of a mid-latitude cyclone?
(4)
- Initial stage
- Development stage
- Mature stage
- Occluded stage
Explain the stages of a mid-latitude cyclone
- Initial stage- cold and warm air meet at the polar front
- Development stage- wave develops along the polar front
- Mature stage- clear low pressure with disinct cold and warm fronts
- Occluded stage- cold front catches up with warm front
What are the weather patterns of a cold front?
(5)
Sudden drop in temperature, air pressure increases, wind changes from NW to SW, cloud cover is thick, rainfall is heavy
What are the weather patterns of a warm front?
(5)
Sudden rise in temperature, air pressure is at its lowest, wind changes from NE to N/NW, cloud cover decreases, rainfall stops
Name the impacts of a mid-latitude cyclone
4
Flooding, snow hazards in high-lying areas, loss of livestock, negative impact on economy
What is the general direction of movement of a mid-latitude cyclone and why?
West to east, because it is driven by westerly winds, therefore moves eastwards
What are the general characteristics of a tropical cyclone? 5
Intense low pressure, named in alphabetical order, during late summer or autumn, move from east to west, away from equator, turns east at 30 degrees, causes destruction by hurricane force winds, storm surges and heavy rainfall
Where are tropical cyclones formed?
In tropical regions, over tropical oceans, further than 5 degrees of equator
What are the conditions of a tropical cyclone? 7
Sea temperature at least 26 degrees Celsius, high humidity, unstable air, little surface friction, light variable winds, air pressure below 950 hPa, air divergence in upper levels
What are the weather patterns as a tropical cyclone storm approaches? 3
Hurricane force winds, air pressure drops, very heavy rainfall
What are the weather patterns in the eye of a tropical cyclone 3
No wind, no clouds, no rain
What are the weather patterns as a tropical cyclone storm moves away? 3
Storm force winds, air pressure increases, heavy rainfall
What are the stages of a tropical cyclone? 4
- Formative stage (above 1000hPa)
- Immature stage (below 1000hPa)
- Mature stage (far below 1000hPa)
- Degenerating stage (rises 1000hPa)
What is the impact of tropical cyclones? 4
- Infrastructure: roads/bridges/pipelines
- Economy: business/crops/costs
- Social: Deaths/property damaged
- Environment: erosion/water polluted
What are strategies for tropical cyclones? 7
Good weather forecasts, keep public informed by tracking storm, early warning systems, medical and rescue services on alert, build houses with strong materials, evacuation routes and procedures, avoid crossing strong-flowing rivers
What is the general direction of movement of a tropical cyclone and why?
East to west, because it is driven by easterly winds therefore moves westwards