[CF-metadata] proposed UTM projection

From: John Caron <caron>
Date: Wed, 02 Feb 2005 10:07:43 -0800

Rich Signell wrote:

> John & Co.,
>
> Why do we need a new projection for UTM?
>
> UTM is just one type of Transverse Mercator that is completely
> specified by the map parameters we already have, right?
>
> From the "Grid Mappings" section of CF 1.0:
>
> grid_mapping_name = transverse_mercator
>
> Map parameters:
>
> * scale_factor_at_central_meridian
> * longitude_of_central_meridian
> * latitude_of_projection_origin
> * false_easting
> * false_northing
>
>
> So people using UTM just specify the appropriate Transvere Mercator
> map parameters for their zone, don't they?
>
>
> -Rich
>
Theres 2 parts:

1) Transverse Mercator doesnt specify the ellipsoidal parameters,
presuming i suppose a spherical earth. Im working with a dataset where
im told the ellipsoidal form is needed for accuracy..

2) The UTM zone specification is in wide use, and is a shorthand for all
the other TM parameters.
Received on Wed Feb 02 2005 - 11:07:43 GMT