gge 5013 lab ii – tidal analysis november 15 th , 2006 ian.church@unb
DESCRIPTION
GGE 5013 Lab II – Tidal Analysis November 15 th , 2006 [email protected]. Tidal Analysis Lab. Perform Analysis on 7 Tide Stations Extract the Harmonic Constituents (T_Tide) Compare Predicted Tides to the Original Tide Extract the Tidal Residuals - PowerPoint PPT PresentationTRANSCRIPT
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Tidal Analysis Lab
• Perform Analysis on 7 Tide Stations• Extract the Harmonic Constituents (T_Tide)• Compare Predicted Tides to the Original Tide• Extract the Tidal Residuals• Explain the Residuals using Meteorological
Data• Compare the Residuals at each Station
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T_Tide
• T_Tide Harmonic Analysis Toolbox for Matlab
• Developed by Rich Pawlowicz at UBC from IOS Tidal Package by Mike Foreman
Fortran Matlab
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Literature
• T_Tide Harmonic Analysis Toolbox for Matlab:
– R. Pawlowicz, B. Beardsley, and S. Lentz, "Classical tidal harmonic analysis including error estimates in MATLAB using T_TIDE", Computers and Geosciences 28 (2002), 929-937.
• IOS Tidal Package Manual:– Foreman, M.G.G., 1977. Manual for Tidal Heights Analysis and Prediction.
Pacific Marine Science Report 77-10, Institute of Ocean Sciences, Patricia Bay, Sidney, B.C., 58 pp. (2004 revision).
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T_Tide Programs
• t_tide.m
• t_predic.m*
• t_demo.m
• t_readme.m
Programs of Interest
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T_Tide Inputs
• Optional:– 'interval'– 'start time'– 'latitude'– 'inference‘– ‘shallow’– ‘…’
• Descriptions can be found in t_tide.m file
help t_tide
• Required:Array of Water Level Elevations [:,1]
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T_Tide Outputs
• Structure:– Constituent Names– Frequency– Amplitude, Amp Error, Phase, Phase Error
• New Predicted Time Series
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Example – Hydrocamp 2006
• St. Andrews, NB
St. Andrews, NB -- June 13th to 19th 2006
0
1
2
3
4
5
6
7
8
164
164
165
165
165
165
166
166
166
167
167
167
168
168
168
168
169
169
169
170
170
170
170
Wa
ter
Le
ve
l (m
)
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Matlab Example
• Load Data into Matlab
• Run t_tide– [Tide_Struct, Pred_Out] = t_tide(TideData,'interval',1/6, 'start time',
StartTime,'latitude',44+38/60);
– Above example for an array of 10 minute tide data
– StartTime is the beginning time of the tidal time series in Matlab serial date format created using “datenum” in Matlab (type “help datenum” in Matlab for usage)
– Latitude is the station latitude
• Save Predicted Tide & Examine Residuals
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Questions?
Station NameSt. John, NB Miguel
Eastport, ME Andy
Cutler, ME Blaine
Yarmouth, NS Shawn
North Head, NB Blair and Scott
Digby, NS Aluizio
Brier Island, NS Pim