The Usefulness of Tidal Charts

Elizabeth Nagy-Shadman, (, Pasadena City College

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This 8-page assignment on the topic of ocean tides is intended to be completed by students alone or in small groups during class (with the possible exception of the last page which requires access to the internet) with the instructor available for help or assistance. It begins by introducing relevant vocabulary and leads students through examples of different tidal patterns. Instructors should make sure that the students have answered these first four pages correctly before moving on to the more challenging scenarios in which students are asked to analyze and make interpretations.

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This assignment is designed for an introductory-level college course in oceanography or other relevant class where ocean tides are discussed.

Skills and concepts that students must have mastered

There are no prerequisite skills required, although the activity does assume that students are familiar with the relationship between lunar phases and spring/neap tides.

How the activity is situated in the course

This activity does not address why there are tides, why there are different tidal patterns, or what factors contribute to tidal variations. This assignment could be used before those topics are taught as an introduction to tides and tidal patterns. As noted above, the activity should come after a discussion of lunar phases and spring/neap tides. Alternatively the activity can be used after all of these other topics have been discussed.


Content/concepts goals for this activity

  • Students will be able to identify diurnal, semidiurnal, and mixed tidal patterns
  • Students will interpret real tidal chart data and make "decisions" about various scenarios that rely on tidal conditions.

Higher order thinking skills goals for this activity

EVALUATION: Interpretation, justifying, explaining.

Other skills goals for this activity

  • Students will become familiar with a global tidal data base accessible via the internet
  • Students will learn about practical situations in which knowledge of the tides is important

Description and Teaching Materials

The handout is pretty self-explanatory. I would suggest giving it to students with at least 45 minutes of class time to work. If the internet is available, the last part can be completed in class. Otherwise this could be assigned as homework.

Tides Handout (Microsoft Word 2007 (.docx) 958kB May22 13)

Teaching Notes and Tips

Although I have provided an answer key, there are some instances where many possible answers would be acceptable, especially for questions 4-7. Also, question 7 asks students to look at CURRENT TIDAL CONDITIONS, so of course you will need to do this as well to grade this part.

Tides Answer Key (Microsoft Word 2007 (.docx) 81kB May22 13)


Here are five possible assessment questions with answers.

Tides assessment (Microsoft Word 2007 (.docx) 836kB May22 13)

References and Resources