Presentation on theme: "1 Last week, we looked at rain, wind and clouds This week we are going to look at weather in different parts of the UK."— Presentation transcript:
1 Last week, we looked at rain, wind and clouds This week we are going to look at weather in different parts of the UK
2 But first we need to think about what makes one place different from another
4 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
5 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?
6 The next bit is quite hard … So if you do not understand it, dont 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, dont worry about it. But I thought I had better explain, otherwise some picky soul would be sure to ask why if I didnt!
8 So there are 2 reasons why it colder at the poles than the equator? What are they?
9 Tilt of the Earths axis towards or away from the sun creates the seasons Earths Seasons North Pole Earth When the north pole tilts toward the sun, it gets more radiation – more warmth during the summer SUMMER (Northern Hemisphere) South Pole WINTER (Southern Hemisphere) When the north pole tilts toward the sun, the south pole tilts away So when its summer in the north, its winter in the south Equator
10 Earths Seasons When the north pole tilts away from the sun, it gets less radiation So its colder during the winter North Pole Earth WINTER (Northern Hemisphere) South Pole SUMMER (Southern Hemisphere) When the north pole tilts away from the sun, the south pole tilts toward it… When its winter in the north, its summer in the south Equator
11 Britains Climate Britains Climate is: Variable - it changes from day to day Temperate – there are never extremes e.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.
12 Temperatures in Britain Average JULY Temperatures across the UK Those little lines are called isotherms Iso means equal Therm refers to temperature So isotherms are lines of equal temperature What do you notice about the average July? Why is that?
13 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?
14 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. Weve now spilt the country into 4 quarters, each having its own characteristic temperature, rainfall and patterns of seasonal change.
15 Where does it 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?
16 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?
17 And this is the difference it can make
18 So in summary Comparing us with say Belgium or Northern Germany Great Britain is cooler in the Summer, warmer in the Winter, and much wetter in the West.
19 Cold winters (<5 0 C) and cool summers and drier Cold winters and warm summers and drier Mild winters (>5 0 C) and cool summers (<15 0 C) & wetter Mild winters and warm summers (>15 0 C) and wetter If >800 mm it is wet Blue line is 5 0 C Jan line, E is colder The red line is the 15 0 C average July temp
20 Where do you think this is? What are the red lines for? January temperature?July Temperature?Rainfall?
21 Where do you think this is? January temperature?July Temperature?Rainfall?
22 Where do you think this is? January temperature?July Temperature?Rainfall?
23 Where do you think this is? January temperature?July Temperature?Rainfall?
24 The answers
25 Take the south west corner first, Devon, Cornwall and the Scilly Isles. Lets spend the winter there….
26...surrounded by sea and bathed in the warm waters of the North Atlantic Drift, an extension of the Gulf Stream, temperatures very rarely fall below freezing. In fact the Isles of Scilly have a mean January temperature of 8 degrees Celsius and sub- tropical plants flourish!
27 Kent and the south east coast of England will be best in summer. Characteristically this quarter experiences both the highest temperatures and the lowest rainfall during the summer months. The area is often overlain by anticyclones or hot, dry air may be drawn in from the Continent, so close to the east.
28 The Lakes or the Highlands and Islands of Scotland are kept mild by the same warm ocean current affecting the south west...