Scientific uncertainty and global warming
Bob Butler, Dexter Perkins
Climate change is the major environmental issue facing all inhabitants of spaceship Earth. As Earth science educators, we must inform students about the scientific consensus on global warming and projections of future warming through this century. Recent research has resulted in a dramatic advance in our understanding of climate history. However, Earth science educators also know that the climate system is complex and there remain considerable uncertainties about details of climate history and the climate system. How do we get across the essential point that Earth scientists agree global warming is real and must be dealt with yesterday while being intellectually honest about the uncertainties about the climate system.
Underlying issues include:
- The nature and process of science.
- The nature of division of opinion and the important point that all perspectives do not have equal merit. There are topics on which a strong scientific consensus exists which amounts to a scientific understanding that is as close to "knowing" as we can get.
- Even in the face of uncertainty, action is warranted if the consequences of inaction are significant.
- Earth science is very effective at retrospection = documenting the history of the Earth in deep time. However, there is much more uncertainty at predicting future events because Earth systems are complex.
So a dilemma we face is whether to address the nature of science in a holistic sense or to focus specifically on the science of global climate change and how to proceed in teaching about climate change.
Kaatje Kraft, Matt Nyman
We believe that this issue provides an excellent opportunity to discuss the nature of science, the beauty of its complexity. The holistic component needs to be addressed outside of the controversial topic so students can appreciate the complexity once they start investigating aspects of global climate change.
- Provide scaffolded examples of how science is done (simple to complex). With examples that illustrate the complex and uncertain nature of scientific process and knowledge. At first focus on examples that do not solicit or generate strong emotional responses.
- Introduce information literacy activities that provide opportunities for students to examine reliability and credibility of sources. For example, have students find methods for predicting earthquakes from multiple sources (e.g., .com versus .edu, peer reviewed versus interest based organization material).
- Provide group work, possibly using a jig-saw strategy, where students examine the data (data from ice cores, ocean surface temperature changes over time, photo evidence of glacial retreat) from different reliable sources that are used to investigate global climate change. Have students draw their own conclusions based on the data presented and class discussions.
- Provide an opportunity for role playing where some students investigate and defend evidence against global climate change and the (possible) anthropogenic correlation. This can lead into a discussion about the complexity of the Earth system and the dynamic nature of models and the uncertainty and peril of making future predictions.