Contrails or Chemtrails?

Blair Larsen, Utah State University
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Using multi-media and basic atmospheric physics, students investigate contrails and chemtrails. Students apply previous learning about pseudoscience, and couple that with an understanding of the atmosphere to reach a decision about chemtrails. Students write an analysis paper on the issue of chemtrails, followed by a decision paper about whether society should be concerned about chemtrails.

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Learning Goals

Content/concepts goals
Students learn the properties of the atmosphere, the layers of the atmosphere, and they apply their knowledge about the process of science to this issue.

Higher order thinking skills goals
Students utilize quantitative methods to interpret results.
Students evaluate the credibility of various sources of information about science-related issues.
Students examine the relationship of the science learned to societal issues.

Other skills goals
Students use written communication to demonstrate knowledge of scientific findings.
Students learn to examine the pros and cons of an issue, and to use credible evidence to make a decision about the issue.

Context for Use

Type and level of course
This activity is used in a general education, non-science major, breadth physical science online course. The course requires students to investigate issues at the intersection of science and society. The students are generally freshmen or sophomores, and most are taking the course because it meets one of their General Education requirements.

Skills and concepts students should have mastered
Students have learned about the physics of the atmosphere. Students have learned how to distinguish science from pseudoscience. Students have learned the course design that leads to decision-making based on evidence.

How the activity is situated in the course
This activity is one module, out of four modules, in my online course. The first module is an introduction to the process of science. The remaining three modules (including this chemtrails one) ask students to investigate, evaluate, communicate, and make an evidence-based decision about an issue at the intersection of science and society.

Description and Teaching Materials

Module 3 Overview

Chemtrails vs Contrails

Identify layers of the atmosphere.
Generally describe the physics of contrails.
Make a logical argument about the effects of contrails.
Analyze the issue of chemtrails and write a conclusion.

I'll provide some links but feel free to do your own research using credible sources. If you find a particularly helpful source, please post it to the Discussion area.

Read about Contrails:
Just what do contrails look like?

how and where contrails are formed:
Make your own contrail
The atmosphere explained
Layers of the atmosphere
Contrail Science
Effect of contrails on ground temperatures
Should you be scared of Contrails or Chemtrails?

Read about the Chemtrails vs Contrails issue:
What are Chemtrails?
Chemtrail conspiracy info
A rally about the Chemtrail threat.

Post to the Reaction to Chemtrails (If-Then) discussion
Contrails Content quiz (you have 2 chances and the quiz is timed)
How should society react to the threat of Chemtrails? Complete and turn in the Analysis product
How should society react to the threat of Chemtrails? Complete and turn in the Decision product
Chemtrails vs Contrails Discussion Post (Microsoft Word 2007 (.docx) 12kB Apr24 17)
Chemtrails vs Contrails Analysis Paper (Microsoft Word 2007 (.docx) 16kB Apr24 17)
Chemtrails vs Contrails Decision Paper (Microsoft Word 2007 (.docx) 16kB Apr24 17)

Teaching Notes and Tips

For this module, the common errors I see involve spelling/typing and grammar/word usage. I provide the students with a link to the Purdue Online Writing Lab to help with this. The other common error I see is that students are unfamiliar with citing sources, or doing so correctly. I give them a bit of latitude with regard to formatting their citations, but I do place a heavy emphasis on crediting sources. Lastly, this topic presents problems for students to find credible evidence for the Pros and Cons of the issue. When this happens, I use the event to reinforce the importance of credibility.


I developed grading rubrics for the Discussion Post, Analysis Paper, and Decision Paper. Those grading rubrics are included in the attached Supporting Materials documents.

References and Resources