Reputation: 5808
How is defined the "0" level in google maps elevation api? The sea is not precisely at 0, and not uniform around the globe, how does it define the sea level?
Upvotes: 1
Views: 758
Reputation: 1332
Geo location maps are based on the position on conventional "Datums" which are approximations of the earth geoid.
The one commonly used in most GPS mapping systems is WGS84, which is used for Google Earth.
The geoid surface is assumed to be "mean sea level", clearly this is an approximation, but is considered practically acceptable.
http://www.icsm.gov.au/mapping/datums1.html
Upvotes: 1