Victoria Hirst
Description of
meteorological
event
Tropical Storms
(hurricanes, cyclones,
typhoons)
Temperate Storms
Tornadoes
Drought
Snow storms/Blizzard
A tropical storm is
a series of low pressure
storms that produce
strong winds and heavy
rain.
Storms with high wind
speed (39-55 mph)
Thunder and lightening
Heavy rainfall
Can last between 12 and
200 hours
A tornado is a violent
rotating column of air
which links the surface
of the earth with a
cumulonimbus cloud,
normally in the form of a
condensation funnel.
Most tornadoes have
wind speeds less than
110 miles per hour
(177 km/h) and are
approximately 250 feet
(80 m) across
Lack of rainfall for an
extended period of
time which leads to a
deficient supply of
water.
Snowstorms are
storms where large
amounts of snow fall.
A large snowstorm
with strong winds is a
blizzard.
Hurricanes develop over
warm water, when water
vapour rises, cools and
condenses to form rain.
Whilst condensing, it
gives off heat which
warms the cool air
higher up and causes it
to rise. This rising air
draws more warm moist
air from the surface
waters, meanwhile a
steep difference in
pressure develops and
draws inwardly spiral
winds that rotate
because of the earth’s
rotational effect
(Coriolis).
Victoria Hirst
Distribution
Started above ocean
waters warmer than
26˚C
Altitude: approx. 5km
More than 500km from
the equator so that the
effect of the earth’s
rotation is big enough.
They occur above warm
sections of the Pacific,
Atlantic or Indian
oceans. Prevailing winds
transport the cyclones
into middle latitudes.
Cyclones are pushed by
jet streams (strong air
currents) from west to
east.
In the northern
hemisphere, hurricanes
rotate anti-clockwise,
and clockwise in the
southern hemisphere.
30-60 degrees latitude
Tornadoes occur most
frequently in USA
Places - North America
Europe: France, UK,
Spain, Germany
Northern Asia: China,
Russia
However, they do occur
on all continents in
various forms.
Most common in rural
areas.
Mainly in latitudes
between 30 and 65
degrees north
446 droughts between
1968 and 1992:
62.8% in Africa
11.8% in Asia
3.4% in Europe
3.4% in Oceania
Permanent droughts
are found in the arid
regions of the world,
such as Australia,
Libya, and Tunisia.
Seasonal droughts are
found in many areas
on the margins of arid
regions where
precipitation levels
change seasonally.
Contingent drought
occurs when lower
than average rainfall
conditions persist for
months or years in
areas where rainfall is
expected to be higher,
therefore the
appropriate
infrastructure to cope
with less rainfall.
Found in high and
mid-latitudes,
blizzards can be very
widespread. They are
most common in
Russia and Central
and Northeastern
Asia, Northern
Europe, Canada,
Northern USA and
Antarctica.
Victoria Hirst
Scale
Type of hazard
Subsequent
hazards?
Localised, but can be
transported to other
regions, making it more
large scale.
Sudden impact
Heavy rain, strong
winds, tornadoes and
storm surges. These can
cause loss of protective
rainforest canopies,
floods or landslides.
Localised
Localised
Can be on a large
scale
Localised
Sudden impact
Large, occasionally
destructive, waves
Flooding caused by
heavy rains.
Thunderstorms caused
by the change in air
pressure
Destruction caused by
strong winds
Sudden impact
Thunderstorms and gale
force winds
Creeping hazard
Soil erosion which can
lead to landslides
Sudden impact
Avalanches