Climate and Weather
Climate can be defined as the average weather and/or as the expected year-to-year variation
in weather variables
The climatic system consists of the atmosphere, oceans, biosphere, cryosphere, lithosphere
Hurricanes in the North Atlantic and eastern Pacific.
Typhoons in the western Pacific, Japan and Southeast Asia
Cyclones in the Indian Ocean.
All major subtropical cyclones
They have wind speeds of more than 120km per hour and can exceed 260km per hour.
Most earthquakes occur along zones where the Earth's crust is undergoing deformation.
Deformation results from plate tectonic forces and gravitational forces.
generally occurs along zones where rocks fracture to produce faults.
Rocks are const
Earthquake Belts and Distribution
Earthquake belts and distribution. Earthquakes occur in welldefined belts that correspond to
active plate tectonic zones. The circumPacific belt (also called the Rim of Fire) follows the
rim of the Pacific Ocean and hosts
Storm surge - fairly accurate
Storm path more problematic
Storm intensity / wind speed problematic
time of arrival moderately predictable
location and magnitude of event specific location of landfall and
Origin of Earthquakes
Most natural earthquakes are caused by sudden slippage along a fault zone. The elastic
rebound theory suggests that if slippage along a fault is hindered such that elastic strain
energy builds up in the deforming rocks on either side
Increasing sea level due to:
wind acting to increase wave height (wind driven surge height depends on wind velocity)
low pressure in eye pressure surge
interaction with tidal conditions
Storm surges occur when the low atmospheric pressure ove
Tropical cyclones form exclusively over tropical seas. Hurricanes and typhoons only can
form over large basins of warm water such as an ocean or sea. This is due to the fact that they
need a large amount of energy which is supplied by the heat from the wa
1. Describe the processes involved in the initiation and development of a tornado, and
discuss the associated hazards.
Tornadoes are narrow funnels of intense wind, typically rotate counter clockwise although a
small proportion rotate clockwise. They desc
Funnel shaped clouds associated with thunderstorms
High velocities (500km/hr) covering a relatively small area
Narrow funnels of intense wind, typically rotate counter clockwise although a small
proportion rotate clockwise. They descend from the
Thunderstorms form as unstable, warm and moist air rapidly rises into colder air
and condenses, it releases heat. Because warm is less dense than cold air, this
added heat will cause the rising air to continue to rise in an updraft. This