**Object Class**: **Tide - harmonic prediction**

**Acronym**: **T_HMON (P,A)**

**Code**: **140**

**Set Attribute_A**: **NOBJNM; OBJNAM; T_ACWL; *T_MTOD; *T_VAHC; STATUS; **

**Set Attribute_B**: **INFORM; NINFOM; NTXTDS; SCAMAX; SCAMIN; TXTDSC; **

**Set Attribute_C**: **RECDAT; RECIND; SORDAT; SORIND; **

**Definition**:

Tide - the periodic rise and fall of the surface of the sea, due principally to the gravitational interactio n between moon, sun and earth. (adopted from IHO Dictionary, S-32, 5th Edition, 5429)

Predicted tidal heights may be calculated using parameters (harmonic constituents) and an appropriate harmonic calculation algorithm.

**References**:

INT 1: not specified;

M-4: not specified;

**Remarks**:

The object 'tide - harmonic predictions' encodes parameters for use when predicting tidal heights by harmonic methods.

The supplier of any parameters must be consulted on how to use this data, and which calculation algorithms to use with the data.

**Distinction**: tide - non-harmonic prediction; tide -
time series;