測地関連のリンク
THE GEOID PAGE(Dennis Milbert)
ＵＲＬ：http://www.ngs.noaa.gov/~dennis/geoid.html
The primary function of this page is to link to resources of interest in geoid research. However, I keep that interpretation rather broad. So, for example, one might find links related to accuracy of GPS ellipsoid heights, or vertical datum issues. Sometimes, commentary is provided, to help place the information in a context.
Geodesy on the World Wide Web
ＵＲＬ：http://www.geomatics.kth.se/hf/geo.html
A List of Web Sites Related to Geodesy and Land Surveying Compiled by Huaan Fan, Royal Institute of Technology, Stockholm
THE GEOMAGNETIC FIELD
ＵＲＬ：http://www.geomatics.kth.se/hf/geo.html
The geomagnetic field measured at any point on the Earth's surface at any time is a combination of the MAIN field internal to the planet, of fields arising from electrical currents flowing in the ionized upper atmosphere, and of fields induced by currents flowing within the Earth's crust. The Main field component varies slowly in time and can be grossly described as that of a bar magnet with north and south poles deep inside the Earth and magnetic field lines that extend well out into space.
