Self Attraction/Earth Load Tide Forcing File (fort.24)

Self attraction/earth load tides are used to force ADCIRC when NTIP=2 in the Model Parameter and Periodic Boundary Condition File.

The format of this file is identical to the “tea” harmonic format with no velocity information included. Entries are grouped by constituents and must be in the same order as the tidal potential terms listed in the Model Parameter and Periodic Boundary Condition File. Phases must be in degrees. Amplitudes must be in units compatible with the units of gravity. These values are modified by the nodal factor and equilibrium argument provided for the tidal potential terms.

The basic file structure is shown below. Each line of input data is represented by a line containing the input variable name(s) in bold face type. Blank lines are only to enhance readability. Loops indicate multiple lines of input. Definitions of each variable are provided via hot links.

for k=1,NTIF

Alpha line

Constituent frequency


Constituent name (e.g., M2)

for j=1,NP


end j loop

end k loop


The first four lines (Alpha line, Constituent frequency, 1, Constituent name) for each constituent must be present in the file but they are skipped over during the ADCIRC read.