Transcript The formation of a depression (powerpoint)

Unfortunately this map showing the highs and lows has
been damaged, can you fix it?
Are we experiencing a high or
a low?
Check it out…….
• http://www.bbc.co.uk/weather/ukweathe
r/pressure.shtml#no_url
Thursday 1pm
How does a depression form?
The stages the formation of a
depression
Pm
Stage 1
Polar air travels
towards tropical
air
Tm
Pm
Stage 2
Tm
Cold polar air starts to cut under
the lighter, warm tropical air
making it rise. The rising air
creates a low pressure on
the ground
Stage 3
Pm
Tm
A spinning depression is
formed with a warm front
and a cold front. Winds
always spin anticlockwise.
Pm
Stage 4
Tm
The depression starts to
die as the warm air
is forced to rise
Stage 5
A dead depression. Winds
die down (isobars spread
apart) and the rain stops
http://whs.moodledo.co.uk/mod/resource/view.php?id=973
5 facts you must remember about
depressions:
1. They are always low pressures (air is being
forced to rise)
2. Always spin anticlockwise in the northern
hemisphere
3. They have a warm sector, cold front, warm
front, and sometimes an occluded front
4. Bring cloud, rain and winds
5. Very common in the UK and Ireland.
Can you add labels to this
map?
Try to add the
following
1.
2.
3.
4.
Centre of Low
Warm front
Cold Front
Warm sector
Can you add labels to this
map?
Try to add the
following
1.
2.
3.
4.
Centre of Low
Warm front
Cold Front
Warm sector
Can you add labels to these
maps?
• http://www.bbc.co.uk/weather/ukweathe
r/pressure.shtml#no_url
• http://www.metoffice.co.uk/
• http://www.weather.org.uk/charts/UKCpf
036.gif
X – Section of a Depression