Anticyclones – High Pressure Task 11 A: Read the Notes on High Pressure

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Anticyclones – High pressure Task 11 A: Read the notes on high pressure. B: Watch the video clip on Anticyclones and sing along! C: Write out the information and fill in the blanks. D: Print/ sketch the diagram and add the labels. E: Using the information on summer and winter anticyclones, fill in the table to identify how they are similar and different in summer and winter F: Write a paragraph describing the hazards for people that are created by summer and winter anticyclones. G: Watch the two video clips on the 2003 European heatwave and write down 10 facts you have learned. H: Quiz, is it an anticyclone or a depression? I: Complete the grid comparing anticyclones and depressions. A WHAT CAUSES HIGH PRESSURE? • When air high in the atmosphere is cold, it falls towards the earth’s surface. • Falling air increases the weight of air pressing down on the Earth’s surface. • This means that air pressure is high • Because the air is falling, not rising there is no clouds forming • A high pressure system is called an ANTICYCLONE. B https://www.youtube.com/watch?v=FCz8J_mxswg C Anticyclones • Anticyclones are areas of high pressure in the atmosphere, where the air is sinking. • High pressure brings settled weather with clear,, bright skies. • As the air is sinking, not rising, no clouds or rain can form. • Winds may be very light . • In summer anticyclones bring dry, hot weather. • High pressure systems are slow moving and can persist over an area for a long period of time, such as days or weeks. sinking high pressure very light slow moving rain clear How to recognise an D anticyclone on a weather map Winds go in a clockwise direction High pressure in the centre means its an •Widely spaced isobars anticyclone •no clouds •isobars showing pressure increasing outwards from the centre Clear Skies Early morning Very little E Light winds frost cloud Puddles may Very cold freeze over and nights fog can form Anticyclones Water pipes may burst and homes Sun low in the in Winter flooded sky Cold, dry days Settled weather for Days can be clear days No rain and bright E Long, sunny Warm Clear, settled cloudless days. temperatures. conditions Dry Early morning Anticyclones dew on the in Summer Very hot grass temperatures may trigger thunderstorms Cold ground temperatures at night Heatwaves High pollen counts E Using the information on summer and winter anticyclones, fill in the table to identify how they are similar and different in summer and winter. Weather features Summer anticyclone Winter anticyclone Temperature Cloud Cover Wind Speed Precipitation Pressure F What hazards for people are created by summer and winter anticyclones G The 2003 European Heatwave https://www.youtube.com/watch?v=7iiTwSWw6eM https://www.youtube.com/watch?v=Hx2940wcooo Write down 10 facts about the 2003 heatwave that you have learned from the videos. H Anticyclone or depression Anticyclone or depression Anticyclone or depression Anticyclone or depression I Low Fill in the blanks comparing depressions and anticyclones. The first one has been done for you .

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