Re: Altitude in meters above WGS-84 Geoid ?

Jim Varney (
Mon, 2 Mar 1998 21:00:42 -0800

Earl Needham wrote:

>>Programs ask for altitude/elevation/height (I'll use all three so I won't
>>restart a thread about the 'proper' use of those terms) above mean sea
>>is that the common number end users have access to.  You're also right
>>the difference between the sea level datum and the spheroid datum makes no
>>practical difference: your 30 meter 'error' relative to a 6378 km earth
>>radius is one part in 200,000.
> So, just to be absolutely sure, I enter 4295 in the height block, because
>that's how high above seal level the ground is here, right?

Yes.  Sea level is good enough.  Don't worry about the geoid stuff (even
though it is interesting).

Jim Varney     121.398 W, 38.458 N, 8m     Sacramento, Calif.
Member, Sacramento Valley Astronomical Society