Storm hazards Flashcards
Outline the distribution of Hurricanes
North Atlantic (Caribbean sea and Gulf of Mexico) (11% of tropical storms) and NE Pacific (western side of central America) (17% of tropical storms)
Distribution of storms in general
Tropical maritime areas between 5-20N/S but not on the equator.
Outline teh distribution of cyclones
South Pacific/Indian - Arabian sea and Bay of Bengal (8% of tropical storms). Off of Madagascar (southeast Africa) 11%
Outline the distribution of Typhoons
Northwest Pacific (off of southeast asia) 33%.
Outline the distribution of Willy Willies
Off north-western and north-eastern Australia (20%)
Give five conditions needed for the formation of a tropical storm
Warm ocean above 27C to at least 70m below the surface
continuous source of heat in order to maintain rising air currents and allow for latent heat to be released by condensation powering the storm. And less frictional drag over the ocean
At least 5-20N/S [1] of the equator so coriolis force can bring about the maximum rotation to the area.
Low level convergence of air [1] forces warm air to rise
Why do tropical storms decay upon reaching land?
Lose source of heat and moisture which provides latent heat when evaporatingIncreased frictional drag with the land surface slows down the storm
In what direction do tropical storms spin in the northan hemisphere?
anticlockwise
In what direction do tropical storms spin in the southern hemisphere
clockwise
What are the four stages of tropical storm formation?
Tropical Disturbance winds less than 23mph
Tropical depression 23-39mph
Tropical storm [1] 39-73 mph
Hurricane: 74 mph +
What scale is used to measure the magnitude of tropical storms?
Saffir Simpson scale
What four factors are measured by this scale?
Central pressure
Wind speed
Storm surge
Damage potential
Describe the frequency of tropical storms in the northan hemisphere
June - November
Describe the frequency of tropical storms Southern hemisphere
November - April
Describe the regularity of tropical storms.
Irregular - occur in same areas but no clear spatial or temporal pattern.