Yukon Albers Projection

The standard projection used by Environment Yukon for spatial data is:



Projection ALBERS
Datum NAD83
Zunits NO
Spheroid GRS1980
Xshift 0.0000000000
Yshift 0.0000000000
61 40 0.000 /* 1st standard parallel
68 0 0.000 /* 2nd standard parallel
-132 30 0.000 /* central meridian
59 0 0.000 /* latitude of projection's origin
500000.00000 /* false easting (meters)
500000.00000 /* false northing (meters)

See SpatialReference.org ESPG:3578 for alternate representations (human readable ESRI or OGC WKT, Proj4, etc.).

Download a .prj file for use with ArcGIS 9.x. For it to appear as an available projection when editing the spatial reference properties unzip it and save it in the ArcGIS\Coordinate Systems folder in the directory where your software was installed.

For ArcView3, download AV3.DEFAULT.PRJ and save it as ...\ARCVIEW\ETC\DEFAULT.PRJ (backup the original, edit path accordingly).

For any program which uses the PROJ4 libraries, like DNR Garmin, open ...\dnrgarmin\proj\nad\epsg in your favourite text editor and add this to the bottom (first verify code 3578 does not already exist):

# NAD83 Yukon Albers
<3578> +proj=aea +lat_1=61.66666666667 +lat_2=68.0 +lat_0=59.0 +lon_0=-132.5 +x_0=500000 +y_0=500000 +ellps=GRS80 +datum=NAD83 +units=m

Why Albers and not UTM?



A non-technical explanation of why Environment Yukon has adopted an Albers projection over UTM and why it doesn't matter to our users. For a technical explanation see British Columbia Albers Standard Projection by the BC Ministry of Sustainable Resource Management.

All coordinate systems are arbitrary. By a coordinate system, we simply mean an alphanumeric system by which the positions of geographic objects can be be unambiguously described. By arbitrary, we mean there's no magic to how these systems were developed...they are completely contrived. Their sole purpose is to enable users to unambiguously describe an object's position in geographic space. It doesn't matter what system you use: spherical (Global Reference System) or planar (Albers, Lambert, UTM, State Plane, etc, etc...), as long as you can place objects in the correct location.

In summary:

  1. a coordinate system allows you to describe an object's geographic position,
  2. the object's position is important,
  3. how the object's position is described (i.e. coordinates) is not important.

The only real issue for us is that if data from a variety of sources are to be integrated, they must all reside in the same coordinate plane. Because of the theoretical limitations of UTM:

  1. UTM zones are limited to 3° on either side of the central meridian,
  2. mapping beyond the 3° limitation results in unacceptable aerial distortion
  3. the Yukon spans 4 UTM zones...

...and the simple fact that our users wish to be able to:

  1. integrate a variety of spatial data,
  2. create maps that span multiple UTM zones

...but don't give a hoot about the actual coordinates, we have abandoned UTM for Albers. Why Albers and not some other non-zonal projection? That's another issue.