The Nature of Science strand

Planet Earth and Beyond

Students compare methods of gathering data about sea temperatures to develop awareness of the practical challenges this entails.

These websites each contribute a different angle to the issue of how sea temperatures can be measured. The Science Buzz website provides a simply worded introduction as an orientation to the issue. The Science Learning Hub provides a deeper slice related specifically to the Argo project. It could be used as a “case study” of just one method. (For example, this video  explicitly discusses the challenges of “covering” the vast Southern Ocean with Argo floats.)

Adapting the resources

Students could begin by building a visual representation (poster, chart, concept map) of the different methods that are used to measure sea temperatures. In small groups have them prepare a reasoned argument for one or both of these questions:

• If you were forced to choose just one of these methods, which would it be and why?
• Why do scientists use more than one method when all of them have their practical challenges and costs?

As they report back, aim to steer the discussion towards an appreciation of the idea of data triangulation: even though each method has its challenges, confidence in the results grows stronger as multiple methods point to similar patterns and trends. 

When something is complex and cannot be measured with one simple and definitive method, it is easier for critics to selectively pick off and discount data. Developing an appreciation for the complexities of data gathering, and knowing some critical questions to ask about methods, is an important aspect of learning to critique both data itself and arguments about the validity and reliability of evidence gathered by others.    

Developing an appreciation of how evidence in science is generated supports students to become scientifically literate, i.e., to participate as critical, informed, and responsible citizens in a society in which science plays a significant role. (This is the purpose of science in NZC.)

Can students provide simple descriptions of multiple methods for measuring sea temperatures?

As they discuss advantages and challenges of these methods, do they show an awareness of the practical complexities of measuring the sea temperature (e.g., sampling, coverage, changes with changing location, depth, cost (who pays?), etc.)

Can they explain why confidence in the data is strengthened when different methods report similar patterns and trends?

For suggestions about adapting tasks in ways that allow students to show progress in critiquing evidence see Progressions .

This recent blog posting  on The Conversation blog site addresses the practical challenges of taking measurements in a different ocean context. Author Jenni Metcalfe clearly and simply describes the challenges of taking population counts of tuna for fisheries regulation purposes.

• I Miss My Pet (L2, 3 & 4) Connected 2, 2006
• Fibres and Fabrics (L2, 3 & 4) Making Better Sense of the Material World
• Magnet investigation (PW3662) (L2, 3 & 4) Assessment Resource Banks
• Which of these materials make the light go on? (L2, 3 & 4) Science Online
• Types of Rubbish (L2, 3 & 4) Figure It Out: Sustainability, Level 2-3, 2010
• Zoom, Zoom! (L3 & 4) Figure It Out: Forces, Level 2-3, 2010
• Butterfly transects (L3 & 4) Monarch Butterfly New Zealand Trust webpage
• Marine Metre Squared (L3, 4 & 5) Mm2.net.nz webpage
• Where will the wood float? (L4) Assessment Resource Banks
• Disinfecting wastewater interactive (L5) Science Learning Hub
• Factors affecting ball bounce (L5) Science Online
• NCEA Level 1 Investigations (L5) NCEA on TKI