Teaching Scientific Certainty: Climate Change and Impact on Biodiversity

This page authored by Tom Huber, Gustavus Adolphus College
Gustavus Adolphus College, Physics
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This module introduces students to the concept of scientific certainty, particularly in the context of climate change, and then how climate departure would impact biodiversity. The first segment of the lesson uses a simple example of a "Wheel of Fortune" game to focus on the meaning of scientific terms such as facts, theory, and experts, and then links this to climate change. The second segment utilizes a group discussion exercise on a fictional airplane engine scenario ("ClyMat Airplane Dilemma") to further explore the role of evidence, experts and the impact of action/non-action; this allows students to explore issues related to climate change in a much less threatening environment without political biases and prior beliefs. In the final segment, students reflect on the potential effects of climate change on biodiversity using a recent paper on climate departure (Mora et al., 2013). It is possible to adjust the length of time devoted to these segments to adapt the module to a wide range of courses.

Used this activity? Share your experiences and modifications

Learning Goals

  • One goal is to give students a better understanding of the meaning of terminology frequently used in science such as fact, theory, evidence, experts, certainty, etc.
  • Another goal is to relate some of these general concepts to climate change. What are the "facts" and what is the "theory" when discussing climate change? Who are the "experts", and is all "evidence" equal?
  • Another goal is to understand the implications of a recent paper on Climate Departure for both human society and for biodiversity.

Context for Use

This module was piloted in a 50-minute upper division Vertebrate Zoology course; all students had taken at least one full year of biology and chemistry prior to this course. The goal of this module was to prepare students for an assignment where they would write a paper on the impact of climate change on a vertebrate species of their choice. Because the students in this course had a very strong background in science, we did not do the "Wheel of Fortune" exercise in the module, but instead moved more quickly into the second segment (group discussion on airplane engine scenario), and concluded with a more extended discussion of impact of climate change on several species using the climate departure paper. The class period was facilitated by a host faculty member (Physics) to a class of ~20 students in the final 1/3 of the semester, situated during the normal class topic of migration as a neurobiological behavior. The was that the host faculty member would be able to teach it unassisted in future offerings of this course.

Because the three segments of the module are somewhat distinct, this module could be utilized in a very wide range of science courses (it would be difficult to do all three segments of the module in their entirety in a single 50-minute period). This same module has been used in a first-term seminar course "Compared to What? The Science of Limits and Extremes, Associations and Relativeness" and the General Education course "Physical World" that was taken mainly by Elementary Education majors. In these courses, there was a greater emphasis on the first segment on the course (meaning of scientific certainty), while in the third segment on climate departure, there was little discussion of the impact on biodiversity.

The first two segments could be utilized in courses in other disciplines such as the humanities or social sciences where the goal is to introduce scientific certainty and climate change.

Description and Teaching Materials

Before Class:
There is a handout (InTeGrate Exercise on Climate Departure for Biology Students Handout) that was distributed to the students a few class periods prior to the lesson. This handout lists the assigned reading:

  • Airplane Engine Dilemma Handout (Read and answer all questions; be prepared to discuss)
  • MinnPost Article on [link http://www.minnpost.com/earth-journal/2013/10/new-look-climate-tipping-points-where-familiar-patterns-vanish- forever 'Climate Departure'] (Read and be prepared to discuss)
During Class:
There is a Powerpoint presentation (Climate Change Scientific Certainty and Biodiversity) that can be utilized.

The first segment, including the "Wheel of Fortune" exercise on scientific certainty will take roughly 10-15 minutes, in part depending on the audience and their background in terminology of science (facts, theory, evidence, certainty). We essentially omitted this section for the upper-division biology class.

For the second segment, students were to have already read through the scenario and discussion questions. We selected a subset of questions for this scenario (for example 1, 2, 4, 6, 8 and 12) and set aside about 15 minutes for students to discuss these questions in small groups, and another 5 minutes to gather for a large-group recap.

For the third segment, the students had read the questions in the "InTeGrate Exercise on Climate Departure for Biology Students Handout" prior to class, so we could briefly work through these in small groups and in the Powerpoint presentation as a large group.

Powerpoint Presentation for Scientific Certainty: Climate Change and Biodiversity (PowerPoint 2007 (.pptx) 3.3MB Jan25 17)

Student Handout: InTeGrate Exercise on Climate Departure for Biology Students (Microsoft Word 2007 (.docx) 386kB Jan25 17)

Student Handout: ClyMat Airplane Engine Dilemma (Microsoft Word 2007 (.docx) 26kB Jan25 17)

Teaching Notes and Tips

For the first segment (Wheel of Fortune), the puzzle that they are trying to solve is the words "Climate Change". We used a white board and recorded both the letters in the puzzle as well as the letters that were not in the puzzle. It is very important to caution students not to "shout out" the answer once they think they know it. You want to take the additional step of making a specific "prediction" to test their "theory." After completing this Wheel of Fortune, go through the slide where you work through what are "facts" (correct and incorrect letters), a "theory", prediction and certainty. On the following slide is the same word in Swedish; unless there is someone in the class who has studied Scandinavian languages, it is unlikely that they would guess that the first letter is a "K" instead of "C"

For the second segment, encourage the students to delve into the discussion of the "ClyMat Engine Problem" without bringing with them prior opinions about climate change. This enables them to explore questions about certainty, expert opinions and action without needing to address political or other biases that sometimes quickly come to the fore when directly addressing climate change. At the end of the discussion, it is helpful to have the students reflect on the similarities (and differences) of the "ClyMat Engine Problem" and climate change discussions.

For the third segment, the most crucial aspect is to insure that they understand the meaning of Figure 1 of the Mora paper: the year at which the climate departs from "recorded history" of at least the last 150 years. Before class starts, pull up from the Mora website (Publication 38) the climate change for a relatively nearby location and be able to show this on the screen. Near St. Peter, MN, the year for climate change was about 25-30 years in the future. Students really seemed to be shocked when I stated that "When you come back for your 25th college class reunion, it will be to a climate that has never existed in the lifetime of anyone alive, or during the 150 year history of the college. It isn't just that the weather will be different, but the annual temperature, rain and snowfall, and patterns of the seasons will be fundamentally changed from what anyone has ever experienced in MN. What do you think the landscape on campus, nearby forests, prairies, lakes and rivers will look like when you return for your 25th class reunion?"


In our initial pilot in the Vertebrate Zoology class, students wrote a paper on the impact of climate change on a species. They were expected to use some of the graphs/tables in Mora's paper to support their arguments.

Other possible assessment methods:

  • Depth and quality of discussion during the lesson
  • An assignment where they make a connection between the relation between the "ClyMat Engine Dilemma" and climate change. For example, what are some "Fake New Sites" related to climate change, versus reputable sources.

References and Resources

Nature article on Climate Departure by C. Mora et al., 2013
The projected timing of climate departure (publication 38) - This webpage allows one to select a point on a world map, and display the climate departure graph

A new look at climate 'tipping points,' where familiar patterns vanish forever - A webpage for the general public that discusses some of the implications of the Climate Departure paper.