Oceanography The Official Magazine of
The Oceanography Society
Volume 26 Issue 04

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Volume 26, No. 4
Pages 164 - 169


HANDS-ON OCEANOGRAPHY • Corals on Acid: An Inquiry-based Activity Leading Students to a Better Understanding of Ocean Acidification Impacts

By Casey L. Boleman , Philip M. Gravinese, Ellen N. Muse , Andrea E. Marston, and John G. Windsor 
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Purpose of Activity
The objective of this inquiry-based lesson is for students to gain an understanding of how increasing ocean acidity can affect the calcification of marine organisms. During this activity, students: (1) design an experiment to quantify the CaCO3 concentration of two invertebrate skeletal samples, one that has been soaked in normal seawater and another in a low pH solution, and (2) use critical thinking and discussion to evaluate possible explanations for the difference in the skeletal CaCO3 compositions. Our lesson focuses on exploring the activity before ocean acidification is introduced to provide a common conceptual framework to engage students. 


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