weather forecasting eg1204 earth systems dr jonathan lageard
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Weather forecasting
EG1204 Earth Systems
Dr Jonathan Lageard
Weather
• ‘Overall state of the atmosphere on a time-scale of minutes to months’ Thomas & Goudie, 2000 p527
• Weather describes specific conditions rain, temperatures, dew-point, wind speed and direction, visibility…
Weather forecasting• ‘The science of predicting the future state of the
atmosphere from very short periods of less than one hour up to 7-10 days ahead’ Thomas & Goudie, 2000 p527
• Climatic regions / climate graphs
• Mid-latitude weather (UK)
• Weather monitoring / forecasting
• Weather & climate practical
content
Global temperature patterns (Jan) Barry & Chorley 2003 p43
Global rainfall patterns Holden, 2005 p39
Holden 2005, p30
Hadley cell regime Thompson 1998, p
Source Flohn 1957 in Barry & Chorley, 1996 p340
Cool Antarctica, 2007
Climate graphs
Landes-Pyrenees Properties, 2007
London climate graph
Weather maps
Air Ministry 1941. The Weather Map. London, HMSO
Stirling, 1997 p25
Synoptic weather chart, Met Office 2000
Stirling, 1997 p28
Weather systems
Air masses: Source regions
Fronts
JetstreamsAerospace Technology, 2007
Mid-latitude weather (UK)
Model of N hemisphere atmospheric circulation Thompson 1998 p107 based on Hanwell 1980
Depressions (cyclonic systems)
a) cross-sectional model
STAGES:
Embryo: Tm & Pm air mix warm air less dense rises in spiral Low Pressure
Mature: Pressure falls warm air rises in warm sector winds inward blowing anticlockwise Coriolis force
Decay: Cold front catches warm front = Occlusion
b) plan form / synoptic chart
What does a depression look like?
Met Office, 2007
Weather associated with the passage of a depression
Waugh 1995, p215Cloud patterns associated with a depression Thompson, 1998 p151
Depression tracks (courses) Stirling, 1997 p30
North Sea storm surge 31st January to 1st February 1953
Impacts:
coastal areas UK, Belgium & Netherlands
Economic damage and community disruption
2,000+ people died across the three countries.
Jonkman SN & Kelman I, 2005
Anticylcones
Large masses of subsiding warm dry air (settled weather)
winds outward-blowing, clockwise
Associated weather
Summer: hot days (heatwave), rapidly cooling night, land-sea breezes, temperature inversions
Winter: similar, but cold / snow, fog / frost
Stirling, 1997 p28
Weather system terminology
Musk, 1988
Weather forecasting: tools / data
Met Office, 2007
Met station, Muckross House, Killarney NP
Instruments: Met Office, 2007
Met Office, 2007
Satellite images
http://www.metoffice.co.uk/
Met Office, 2007
UK observations regional map (Met Office, 2007)
Met Office, 2007
Met Office, 2007
‘We interrupt TMS to bring you the following gale warning issued by the Met office at 17.25 GMT Wedesday 14th March…’
Directed reading:
• Mountain weather / local climates – Holden 2005 pp80-96
• UK weather system variants Met Office 2007 – Learning – Weather resources – Higher - weather systems
• Hurricanes (storm of 1987 – Met Office, 2007, Barry & Chorley 2003 pp269-275)
Suggested reading
• Barry RG & Chorley RJ 2003. Atmosphere, Weather and Climate (8th Edition). London, Routledge.
• Earth Science and Geography, Keele University 2007. The Weather at Keele (Keele Weather station).
http://www.esci.keele.ac.uk/weather/ (accessed 13.3.07)• Holden J (Ed) 2005. An Introduction to Physical Geography and the
Environment. Harlow, Pearson. (Atmospheric processes, global climates, local & regional climates pp27-96).
• Met Office 2007. Met Office homepage. http://www.metoffice.gov.uk/index.html (accessed 12.3.07) Folllow links to Learning – Weather resources - Higher
• O’Hare G, Sweeney J & Wilby R 2005. Weather, Climate and Climate Change. Harlow, Pearson.
• Stirling R 1997. The Weather of Britain. Routledge.• Thomas DSG and Goudie A 2000. The Dictionary of Physical
Geography. Oxford, Blackwell. • Thompson RD 1998. Atmospheric Processes and Systems.
London, Routledge.