1 Reply by adamwalmsley

  • adamwalmsley
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Re: Five figure grid reference

Hello,
I have come across some five figure grid references in data downloaded from NBN gateway. Would someone be able to explain these to me please. They comprise the 100km square code, two numbers and then a letter e.g. SD82B
I just don't know what this last letter means.
Thanks

2 Reply by RobLarge

  • RobLarge
  • RobLarge
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Re: Five figure grid reference

They are tetrad records (clusters of four 100km squares, of which there are 25 in a 10km square). This is a system widely used for large scale recording excercises.

Google it or follow the follwing link http://en.wikipedia.org/wiki/Tetrad_%28area%29

Rob Large
Wildlife Sites Officer
Wiltshire & Swindon Biological Records Centre

RobLarge's Website

3 Reply by charliebarnes

  • charliebarnes
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Re: Five figure grid reference

They are 2km DINTY grid references - see http://www.kmbrc.org.uk/recording/help/gridrefhelp.php?page=6

Charlie Barnes
Information Officer
Greater Lincolnshire Nature Partnership

charliebarnes's Website

4 Reply by adamwalmsley

  • adamwalmsley
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Re: Five figure grid reference

Thanks Rob and Charlie :)