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Open-File Report 2015-1033

Coastal Change Processes Project Data Report for Oceanographic Observations Near Fire Island, New York, February Through May 2014


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Tidal Analysis

Amplitude and phase of principal tidal constituents were computed by using the tidal analysis program T_TIDE (Pawlowicz and others, 2002). The principal constituents are K1, O1, M2, N2, and S2. The full output from T_TIDE for ADCP current and pressure data records are linked below. The duration of time series used to compute the harmonics is different for each instrument and depends on instrument deployment and recovery times (see Instrument Log) and data availability. The following is a list of the headings used in the tables for the T_TIDE output and a brief description:

Table headings for T_TIDE output:

  • tide: tidal constituent
  • freq: frequency (cycles per hour)
  • major: major axis of tidal ellipse (for current observations) (centimeters per second [cm/s])
  • emaj: error estimate for major axis (cm/s)
  • minor: minor axis of tidal ellipse (cm/s)
  • emin: error estimate for minor axis (cm/s)
  • inc: inclination of major axis (counter clockwise from east) (degrees)
  • einc: error estimate for inclination (degrees)
  • phase: phase of major axis (degrees)
  • ephase: error estimate of phase (degrees)
  • snr: signal-to-noise ratio
Site Pressure Current velocity
Near Surface Near Bottom
1 ADCP Output Output Output
2 ADCP Output Output Output
3 ADCP Output Output Output
6 ADCP Output Output Output
7 ADCP Output Output Output
8 ADCP Output Output Output
9 ADCP Output Output Output


Significant constituents (those with SNR ratio in the last column > 1) are marked with an asterisk.