Satelliten- und Aerogeophysik

TriTop - Adaptive topographic correction


TriTop is a Java based software package which has been developed by Nils Holzrichter. The JAVA implementation provides a software platform independent of operating systems. The program has a graphical user interface

The program needs two input files. Station coordinates (longitude, latitude, height)  and a topography grid in geographical coordinates. The software is capable to download the necessary topography grid for a desired area automatically. It downloads data from the ACE2 server ( and crops the tiles down to the given limits. The user can choose between 3 grid resolutions as provided by the ACE2 consortium: 3'', 9'' and 5'. If the highest resolution is not available everywhere in the chosen area, the program downloads also a coarser grid and merges both datasets. The final topography file does not include any NANs (not a number). It is also possible to import a self-derived topography grid.

The correction algorithm uses an adaptive or a classic approach (user choice) based on a polyhedral approximation of topography.