When tide observations from a single station are applied to a track line (or lines), the time extent of the line(s) is used. The illustration below shows tide values from a single station applied to three selected track lines, based on the time each line was recorded.
Tide data from a single station is loaded from files with the extension *.tid. These files can be created or edited in a text editor (such as Notepad), or with the Tide Editor.
HIPS supports a standard Canadian Hydrographic Service tide format called COWLIS, as well as two NOS/NOAA formats and the NHS file format. HIPS also supports a basic format consisting of just the required date, time, and tide values.
Track lines in areas without water level changes, such as rivers or lakes, must also have a tide file. In this case, or if tidal data cannot be obtained, a “zero tide” file—where all tide/time values are zero—is used so merging can proceed.
For more detail, see Tide File Formats.