Graphing utility for ocean currents

This utility plots self-generated or imported ocean current data in a variety of graphic representations. See end of page for instructions and explanatory notes.

This page combines JavaScipt with a Java applet. See the Utilities entry page for browser requirements.

Self-generated demonstration data. Set the parameters (m/s and degrees):

slowly varying mean current magnitude:   direction: 
plus tidal current (12 hour period) magnitude: axis ratio:
plus damped inertial oscillation magnitude:

Own data (click on "enter own data" and scroll down for instructions)


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Verify your data against the graph.

  xmin: xmax: ymin: ymax:


Instructions: The self-generated demonstration data consist of a slowly varying mean flow with a 12-hour period tidal current and a slowly decaying inertial current with a period of 18 hours. Each component can be controlled individually or eliminated by assigning it zero magnitude. The major axis of the tidal ellipse points east-west, the minor axis north-south. The length of the time series is 10 days (240 hours).

To generate the current set the magnitudes and directions and press GENERATE THE DATA. The data for the first day will be displayed in the window. Move through successive days by pressing > or < under the window.

To enter own data press ENTER OWN DATA and follow the instructions that will appear in the window. Select the entire window text and replace it with your data, either by typing the data directly into the window as time, east component, north component separated by commas and one group per line, or by pasting data in from a spreadsheet or text processor. When all data in the window are complete press SUBMIT. This produces a display of the data as they are accepted by the programme. Press RESTORE DATA to return to the data in their original form if further editing is required. RESET clears the entry field.

To plot the data displayed in the window click on the type of graph you want to generate (components, speed and direction, etc.). This changes the data display to the appropriate variables. Press TRANSFER DATA TO APPLET, set the scales by pressing SET SCALES and press GRAPH.

To edit a graph edit the data in the window on the left, press RESET in the applet and repeat the plotting procedure.

NOTES:

This utility is related to the material presented in Exercise 2 of Advanced Exercises in Physical Oceanography.

© 2000 M. Tomczak
Graphing applet © 2000 Mariusz Bajger

Last updated 9 March 2001.

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