Climate and CO2
Summary
This lab introduces students to the concept of climate sensitivity. Students use ice core data and older paleoatmospheric CO2 and temperature data (available on paleo-co2.org) to calculate climate sensitivities over different timescales. They are asked to reflect on why climate sensitivities might vary. In order to help students put the magnitude of climate sensitivities they calculate into some sort of context, they are then asked to find two cities whose mean annual temperature difference equals the sensitivities they calculated. Finally, students are asked to find, using a online tool, a 'solution' to future change by limiting warming without increasing energy costs more than a prescribed amount.
Keywords:
Climate, CO2, paleoclimate, sensitivity, carbon cycle, policy
Learning Goals
The content/concept goals include: understanding what climate sensitivity is and the kinds of data used to calculate it, introduction to where those data are available, contextualizing past climate change by comparing with spatial variability on the modern Earth.
The higher-order thinking goals include: integrating an understanding of feedbacks and Earth System processes into interpretation of climate sensitivity.
The goals for other skills involve: use of spreadsheets, practice with unit conversions, to encoruage thinking about challenges we face due to climate change.
Context for Use
This activity is a lab assignment in an introductory Earth Science class at UT Austin. At UT Austin, the lab sessions have <=20 students each and are instructed by a teaching assistant. The 2-hour lab period in which students are asked to complete this assignment occurs after two 75 minute lectures on climate. A lab manual style "chapter" is provided as part of the activity and contains most of the climate-related background information students need to complete the assignment. The activity could be assigned during an hour-long class period and/or as a homework assignment.
Students will need access to the internet and need to be able to download a CSV file and upload it to google sheets (or open in another spreadsheet program) in order to complete the assignment in its entirety. A workaround is to ask students to estimate the mean value of data displayed on a plot.
Description and Teaching Materials
All materials are available as downloadable files (an instructor version and a student version) that contain urls. The downloadable files contain the activity and a brief introductory "chapter" to climate and CO2.
Student Handout for Climate and CO2 Assignment (Microsoft Word 2007 (.docx) 6.8MB Sep18 25)
Instructor Version of Climate and CO2 Assignment (Microsoft Word 2007 (.docx) 6.8MB Sep18 25)
Teaching Notes and Tips
The activity asks students to calculate climate sensitivity using the log base 2 function. Many students are unfamiliar with this function and with the concept of fractions of a doubling (which log2 can quantify). Some introduction to that concept might be helpful. Otherwise, the math in the activity is straightforward, involving averages and unit conversions.
The activity refers to a plot with four panels on the paleo-co2.org homepage. The user can only zoom in using the bottom left panel. This can be frustrating for students. A demonstration of how to zoom is recommended.
Assessment
A scoring rubric is included. I consider goals to have been met if the assignment is completed with a score of 80% or higher.
References and Resources
The urls for several online resources are included in the activity.