Tropical Cyclones

Question 1

Characteristics

Answer 1

Low pressure ( below 1000hPa)
Between 5° and 30° N and S
Develops over tropical oceans (above 27°)
East to west
Occur in late summer after long period of heating
Affect east coast of continents
Die out rapidly over land (increased friction & lack of moisture)
Smaller in size compared to mid-latitude cyclones.
Reach diameters of 400-600km

Question 2

Necessary for formation

Answer 2

Warm tropical oceans (above 27°) ; high evaporation
Over oceans; less friction + warm moist air rises
Beyond 5° N & S; coriolis force too weak to cause air to spin around LP centre
Surface air convergence ;air forced to rise when converging
Upper air divergence;more moist drawn in.Cooler air diverges at top of system
Condensation; large-scale condensation of rising moist air = latent heat from cooled air. Promotes instability = formation of system
Winds must be light and variable

Question 3

Active quadrant

Answer 3

Cyclone moving same direction as the wind resulting in stronger winds.

Question 4

Vortex 1

Answer 4

Temp decreases
Pressure decreases
Cumulonimbus clouds bigger
Wind speed increases
Rough seas and storm surges
Most intense features here: torrential rain, hail, thunder, lightning, and destructive wind speeds of 180km/h from the S

Question 5

Eye

Answer 5

Temp increases slightly
wind speed drops
Air is calm with clear skies; no rain
Pressure is at its lowest

Question 6

Vortex 2

Answer 6

Storm intensity >
Temperatures initially drop then start to increase
Wind speed is initially very strong, slows down as it moves away
Pressure starts to increase and eventually conditions clear.

Question 7

Impact of tropical cyclones on humans & environment

Answer 7

1. Flooding due to torrential rain and rising river flow = mudslides & landslides
   Coastal flooding from storm surges
   Damage and destruction to buildings and infrastructure
   Agricultural lands and crops are damaged
2. Torrential rain
   High wind sped (up to 300 km/h)
   Mini tornadoes
   Extremely LP
3. Swell waves up to 10m out of sea
   Storm waves
   Storm surges along coastline ; coastal flooding
4. Drowning
   Loss of homes
   Disease outbreaks and eventually starvation
   Economies that rely on monoculture may experience great losses
   Loss of workplaces and jobs
   Major financial strain on people, people and businesses

Question 8

Precautions

Answer 8

Avoid driving on flooded road
Make sure you have flooding insurance
Know communities evacuation plan
Small to medium boats and fishing