Sorry Ross,
WGS84 is a reference coordinate system while UTM is a Cartesian coordinate
system (I am certain someone will correct me). See the following links to
Wikipedia for the difference.
http://en.wikipedia.org/wiki/Universal_Transverse_Mercator_coordinate_system
http://en.wikipedia.org/wiki/World_Geodetic_System
http://www.ga.gov.au/geodesy/datums/aboutdatums.jsp
GDA94 is almost identical (less than 5?m) to WGS84.
The main difference I think is that one uses figures (Latitudes and Longitudes)
for the whole earth while UTM (or equivalents such as MGAs) break the world
down into Zones and then has Eastings and Northings (in Australia Eastings
range between about 200000 and 700000 metres per zone - and I think Northings
may cover a larger area - they are a 7 digit figure).
Anyway - I think Australian birders obsession with lat/longs goes back to first
Atlas where most maps were easy to divide up into 10 minute grids (many were
also still in miles and feet) but in these enlightened metric days I would far
rather grid references supplied as Z,E,N.
Cheers,
Peter
Interesting - my e-mail about missing e-mails turned up in the archives but I
haven't received it.
> From:
> To: ; ;
> Subject: Re: [Birding-Aus] RE: Decimal Vs Sexagesimal Notation
> Date: Wed, 12 May 2010 19:42:00 +1000
>
> The Victorian Malleefowl Recovery Group uses WGS 84 which I think is UTM for
> all our GPS nest locations...
>
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