[Proj] True North Angle

[Dean C.Mikkelsen]

Hi Willy,

Please take a look at:

http://cgc.rncan.gc.ca/geomag/field/magdec_e.php

The difference between True North and Magnetic North 
changes over time.

The Australian's also have a good site and it is located 
here:

http://www.ga.gov.au/oracle/geomag/agrfform.jsp

Let me know if you have any questions.

Cheers,
Dean



On Mon, 23 Jun 2008 07:52:21 -0800
  "Hersman, William" <willy.hersman at conocophillips.com> 
wrote:
> Hello,
> 
> Does anyone know the formula to calculate the deviation 
>angle between
> true north and Universal Transverse Mercator grid north? 
> Thanks.
> 
> Willy Hersman

Dean C. Mikkelsen, B.Sc., P.Eng.

E-mail: dcmikkelsen at terraetl.com

http://www.terraetl.com