Oceanography The Official Magazine of
The Oceanography Society
Volume 24 Issue 04

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Volume 24, No. 4
Pages 136 - 142


HANDS-ON OCEANOGRAPHY • Lake in a Bottle: A Laboratory Demonstration of the Unusual Stability Properties of Freshwater

By Jay A. Austin , Emily B. Voytek , Julia Halbur, and Messias A. Macuiane 
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Purpose of Activity

Using simple laboratory gear, students can simulate the stratification properties of a freshwater lake and the impact of salt on the relationship between temperature and density. Because some students have little or no intuition for different thermal stratification regimes, this activity is designed to focus on this fundamental behavior of freshwater lakes. The experiment exposes students to basic data collection, analysis, and visualization techniques using an inexpensive, commercially available data logger and sensors. It can be used as motivation for a discussion of sampling techniques, such as sampling density and sampling rate, and how choosing among them can influence the reliability of an experiment’s results. 


Austin, J.A., E.B. Voytek, J. Halbur, and M.A. Macuiane. 2011. Hands-on oceanography: Lake in a bottle—A laboratory demonstration of the unusual stability properties of freshwater. Oceanography 24(4):136–142, https://doi.org/10.5670/oceanog.2011.107.


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Peeters, F., D. Finger, M. Hofer, M. Brennwald, D.M. Livingstone, and R. Kipfer. 2003. Deep-water renewal in Lake Issyk-Kul driven by differential cooling. Limnology and Oceanography 48:1,419–1,431, https://doi.org/10.4319/lo.2003.48.4.1419.

Vollmer, M.K., H.A. Bootsma, R.E. Hecky, G. Patterson, J.D. Halfman, J.M. Edmond, D.H. Eccles, and R.F. Weiss. 2005. Deep-water warming trend in Lake Malawi, East Africa. Limnology And Oceanography 50:727–732, https://doi.org/10.4319/lo.2005.50.2.0727.

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