Transcript Grid References (MS Powerpoint Slideshow)

GRID REFERENCES
MADE EASY
FOR
CAMPING CLUB YOUTH
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GRID REFERENCES MADE EASY
A GRID REFERENCE is a number which
gives a location on a map
They are very useful when we’re out hiking
We can use them to find out where we’re
supposed to be…
...or if we get lost we can tell someone
where we are!
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GRID REFERENCES MADE EASY
The grid references we usually use are
SIX FIGURE references
They will look something like this:
216409
A bit like a phone number!
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GRID REFERENCES MADE EASY
These numbers refer to the GRID which
covers all maps
Here they’re marked in PINK so you can
see them, but they’re usually BLUE
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GRID REFERENCES MADE EASY
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The grid is labelled with GRID
NUMBERS at the bottom and left sides
of the map
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40
20
21
22
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GRID REFERENCES MADE EASY
The numbers at the bottom are called
EASTINGS because they label grid lines
which go EAST
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20
21
22
23
GRID REFERENCES MADE EASY
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The numbers at the Left are called
NORTHINGS because they label grid
lines which go NORTH
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40
GRID REFERENCES MADE EASY
Each Easting refers to the column to the
right of it’s grid line
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21
GRID REFERENCES MADE EASY
Each Northing refers to the row above
it’s grid line
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40
GRID REFERENCES MADE EASY
Where are these EASTINGS and
NORTHINGS in the Grid Reference?
40
21
216409
EASTING
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NORTHING
GRID REFERENCES MADE EASY
Both numbers combined give a square
on the map...
The grid
reference of this
square is 21 40
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40
21
GRID REFERENCES MADE EASY
How do you remember WHICH COMES
FIRST though?
Well, just remember
EASTINGS FIRST
…and that EASTINGS are the numbers
along the bottom, labelling the lines that
go EAST!
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GRID REFERENCES
MADE EASY
EXERCISE ONE
FIND THE SQUARE
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You’ll have a map between two, and a list of 6 figure grid
references - just find the big square for each one
GRID REFERENCES MADE EASY
OK so we now know how to find the
square from these numbers:
6409
216409
21
But what about these ones?
What are they for?
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GRID REFERENCES MADE EASY
Well the 21 and 40 only give you a big
square one kilometre wide!
1km
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40
21
Not much use if
you need to
know where to
go exactly!
GRID REFERENCES MADE EASY
So we split each square into 100 smaller
squares...
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GRID REFERENCES MADE EASY
Each square is labelled like the
grid before, but with just one
number from 0 to 9
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9
8
7
6
5
4
3
2
1
0
0 1 2 3 4 5 6 7 8 9
GRID REFERENCES MADE EASY
So, same as before, a square is identified by
an EASTING and a NORTHING
Remember, EASTING first
So what’s the
two numbers
which identify
this square?
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9
8
7
6
5
4
3
2
1
0
0 1 2 3 4 5 6 7 8 9
GRID REFERENCES MADE EASY
That’s right: 4 and then 7
4 first as it’s the EASTING
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9
8
7
6
5
4
3
2
1
0
0 1 2 3 4 5 6 7 8 9
GRID REFERENCES MADE EASY
Then 7 as it’s the NORTHING
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9
8
7
6
5
4
3
2
1
0
0 1 2 3 4 5 6 7 8 9
GRID REFERENCES MADE EASY
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OK, let’s put it all together…
See the spot height marked 375 in the
square below?
41
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40
20
21
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GRID REFERENCES MADE EASY
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Let’s find out it’s full 6 figure reference
______
41
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40
20
First, what square is it in?
21
22
23
GRID REFERENCES MADE EASY
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Yes, 21 - 40!
But where does this fit into the 6 figure
reference?
41
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40
20
21
22
23
GRID REFERENCES MADE EASY
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21____
21 first
41
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40
20
21
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GRID REFERENCES MADE EASY
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21_40_
Then 40
41
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40
20
21
22
23
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Both together...
41
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40
20
21_40_
21
22
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GRID REFERENCES MADE EASY
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Now we need to look at the missing two
figures:
21_40_
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40
20
21
22
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GRID REFERENCES MADE EASY
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21_40_
So we add the grid - usually you do this
in your mind!
41
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40
20
21
22
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GRID REFERENCES MADE EASY
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21_40_
The spot height is in this square
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40
20
21
22
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GRID REFERENCES MADE EASY
9 Zooming in...
8
7
2
212
_40_
6
5
4
3
2
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1
0
0
1
2
3
4
5
6
7
8
9
GRID REFERENCES MADE EASY
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So now we have the full grid reference:
212402
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40
20
21
22
23
GRID REFERENCES MADE EASY
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41
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OK, what about the station in Llangollen?
______
40
20
21
22
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GRID REFERENCES MADE EASY
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41
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OK, what about the station in Llangollen?
214422
40
20
21
22
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GRID REFERENCES MADE EASY
OK, where’s this one...
204408
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41
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40
20
21
22
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GRID REFERENCES MADE EASY
OK, where’s this one...
204408 Answer: Bank Fm
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41
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40
20
21
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Camping Club Youth
EXERCISE TWO
PRACTISE MAKES PERFECT
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You’ll have a map between two, challenge each other to give
the grid ref for a place, and the places for given refs