Exercise 2.6
Understanding Weather Maps
Isobars: lines joining places of equal pressure,
the closer the isobars the stronger the winds.
High-pressure system: area of sinking air, generally
fine weather. Winds rotate in an anti clockwise direction.
Low-pressure system: area of rising air,
generally cloudy weather and a good chance of rain.
Winds rotate in a clockwise direction.
Tropical cyclone: area of rapidly rising air.
Tropical cyclones are often torrential rain and brutal
forced, destructive winds rotating in a clockwise
direction. They are always given a name eg. Tropical
cyclone Pamela.
Cold front: separates warm and cold air, cold air
behind the front. Brings a fall in temperature,
sometimes rain and storms. Moves in the direction
of the arrows.
Warm front: separates warm and cold air,
warm air behind the front. Brings an increase in
temperature and sometimes light showers,
uncommon in Australia.
QUESTIONS
Q1. What is another name for a weather map?
Synoptic chart
Q2. List three differences between a high and low-pressure system
High pressure= air sinking, rotating anticlockwise, generally fine weather
Low pressure= air rising, rotating clockwise, generally cloudy weather
Q3. What does a weather map indicate when…
a. Isobars are close together? Strong winds
b. Isobars are far apart? Hardly windy