1 Last week, we Last week, we looked at rain, looked at rain, wind and clouds wind and clouds This week we are going This week we are going to look at weather in to look at weather in different parts of the different parts of the UK UK
Dec 14, 2015
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Last week, we Last week, we looked at rain, looked at rain,
wind and cloudswind and clouds
This week we are going This week we are going to look at weather in to look at weather in
different parts of the UKdifferent parts of the UK
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But first we need But first we need to think about to think about
what makes one what makes one place different place different from anotherfrom another
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Also air from the sea has more water vapour in it, so it tends to be wetter than inland – remember relief rainfall from last week
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What is it like to live by the sea?What is it like to live by the sea?
Is it likely to be wetter or drier? Why?
Will winters be warmer or cooler? Why?
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The next bit is quite hard …The next bit is quite hard …
So if you do not understand it, don’t worry about it.The only thing you need to get out of it is that there is a temperature difference between places near the equator and places near the North and South Pole.The next couple of slides explain why that is – but as I said – if you find it too confusing, don’t worry about it.But I thought I had better explain, otherwise some picky soul would be sure to ask why if I didn’t!
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So there are 2 So there are 2 reasons why it colder reasons why it colder at the poles than the at the poles than the
equator?equator?
What are they?What are they?
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This diagram shows how (a) the earth is This diagram shows how (a) the earth is tilted and (b) how it moves around the tilted and (b) how it moves around the
sunsun
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Tilt of the Earth’s axis towards or away from the sun creates the seasons
Earth’s Seasons
North Pole
Earth
When the north pole tilts toward thesun, it gets more radiation – more warmth
during the summer
SUMMER (Northern Hemisphere)
South Pole
WINTER (Southern Hemisphere)
When the north pole tilts toward thesun, the south pole tilts away
So when it’s summer in the north, it’s winter in the south
Equator
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Earth’s Seasons
When the north pole tilts away from the sun, it gets less
radiation So it’s colder during the winter
North Pole
Earth
WINTER (Northern Hemisphere)
South Pole
SUMMER (Southern Hemisphere)
When the north pole tilts away from thesun, the south pole tilts toward it…
When it’s winter in the north, it’s summer in the south
Equator
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Britain’s ClimateBritain’s Climate
Britain’s Climate is:Variable - it changes from day to dayTemperate – there are never extremese.g it is never too anything [hot, dry, wet, cold]Maritime- proximity to ocean affects our weather
Britain is renowned for cool summers and mild winters.
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Temperatures in BritainTemperatures in BritainAverage JULY
Temperatures across the UK
Those little lines are called isothermsIso means equalTherm refers to temperatureSo isotherms are lines of equal temperatureWhat do you notice about the average July? Why is that?
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Average JANUARY Temperatures across the UK
What do you notice about the isotherms in January?Why do you think that might be?What do you know about the sea cooling and warming up?
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In fact it could be said that we have 4 climates! Imagine a line from north to south through the centre of the country, this is the 5-degree Celsius January isotherm; and another from west to east, again through the centre, is the 15-degree Celsius July isotherm. We’ve now spilt the country into 4 quarters, each having its own characteristic temperature, rainfall and patterns of seasonal change.
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Where does it Where does it rain?rain?
The 2 dark blue colours is where there is more than 1300mm of rain a year.How many cm tall are you? Where would that amount of rain come up to?What do you notice about where the dark blue bits are?Any ideas why?The brownest areas are where? What does that mean?
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Why is it wetter in parts of the UK?Why is it wetter in parts of the UK?
It is wetter in the west because our prevailing wind is SW ( along with the gulf stream)SW winds come across the Atlantic, picking up lots of water vapour as they travel.But why do the clouds seem to drop most of it when they hit the land? Do you remember what that kind of rainfall is called?
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So in summarySo in summary
Comparing us with say Belgium or Northern GermanyGreat Britain is cooler in the Summer, warmer in the Winter, and much wetter in the West.
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Cold winters (<50C) and cool summers and drier
Cold winters and warm summers and drier
Mild winters (>50C) and cool summers (<150C) & wetter
Mild winters and warm summers (>150C) and wetter
If >800 mm it is wet
Blue line is 50C Jan line, E
is colder
The red line is the 150C
average July temp. S is warmer
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In your atlas on pages 12/13 you see lots In your atlas on pages 12/13 you see lots of graphs like this. What do you think it of graphs like this. What do you think it
shows?shows?
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Now I could do graphs Now I could do graphs like that for the UK – like that for the UK –
but they are a bit but they are a bit confusingconfusing
As everywhere in the UK gets rain all year in about equal measure – it is just the total that varies, we are going to look at slightly different
graphs
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Where do you think this is?Where do you think this is?
January temperature? July Temperature? Rainfall?
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Where do you think this is?Where do you think this is?
January temperature? July Temperature? Rainfall?
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Where do you think this is?Where do you think this is?
January temperature? July Temperature? Rainfall?
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Where do you think this is?Where do you think this is?
January temperature? July Temperature? Rainfall?