Everything about Physical Geodesy totally explained
Physical geodesy is the study of the physical properties of the
gravity field of the Earth, the
geopotential, with a view to their application in
geodesy.
Measurement procedure
Traditional geodetic instruments such as
theodolites rely on the gravity field for orienting their vertical axis along the local
plumb line or local
vertical direction with the aid of a
spirit level. After that, vertical
angles (
zenith angles or, alternatively,
elevation angles) are obtained with respect to this local vertical, and horizontal angles in the plane of the local horizon, perpendicular to the vertical.
Levelling instruments again are used to obtain
geopotential differences between points on the Earth's surface. These can then be expressed as "height" differences by conversion to metric units.
The geopotential
The Earth's gravity field can be described by a
potential as follows:
» is our earlier
, the free-air anomaly.
In case the terrain isn't a flat plate (the usual case!) we use for
H the local terrain height value but apply a further correction called the
terrain correction (
TC).
Further Information
Get more info on 'Physical Geodesy'.
|
External Link Exchanges
Do you know how hard it is to get a link from a large encyclopaedia? Well we're different and will prove it. To get a link from us just add the following HTML to your site on a relevant page:
<a href="http://physical_geodesy.totallyexplained.com">Physical geodesy Totally Explained</a>
Then simply click through this link from your web page. Our crawlers will verify your link, extract the title of your web page and instantly add a link back to it. If you like you can remove the words Totally Explained and embed the link in article text.
As long as your link remains in place, we'll keep our link to you right here. Please play fair - our crawlers are watching. Your site must be closely related to this one's topic. Any kind of spamming, dubious practises or removing the link will result in your link from us being dropped and, potentially, your whole site being banned. |