Abrupt climate change, greenhouse gases, and the bipolar see-saw
University of California, Irvine
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In this activity, students work with paleoclimate proxy data (d18O, CH4, CO2)from the Byrd and GISP2 ice cores. Students prepare a graph of paleoclimate data and use the graph to answer several questions about the timing and mechanisms of millennial-scale climate and greenhouse gas changes during the Last Glacial/Deglacial time periods.
This is used for a 5-week graduate level Paleoclimate course taken by all 1st year PhD students in the Dept. of Earth System Science at UC Irvine.
Skills and concepts that students must have mastered
Students must be familiar with some sort of graphics software (e.g. Excel, Matlab, Sigmaplot, etc.) and have a working understanding of ice core delta18O, CO2, and CH4 records.
How the activity is situated in the course
This is a stand-alone exercise that is assigned as the 2nd of two homework assignments in this course (during Week 4).
Content/concepts goals for this activity
-Preparing graphics for publications
-Comparison of paleoclimate records
-Mechanisms of orbital and millennial scale CH4 and CO2 variations
Higher order thinking skills goals for this activity
analysis of data
synthesis of ideas
critical evaluation of abrupt climate change mechanism
Other skills goals for this activity
Designing publication quality graphics
Description of the activity/assignment
In this activity, students work with paleoclimate proxy data (d18O, CH4, CO2)from the Byrd and GISP2 ice cores to investigate millennial-scale climate changes during the Last Glacial/Deglacial time periods. Students must prepare a publication quality plot of the data and answer several questions about the similarities and differences between the time-series (north-south phasing, amplitude, symmetry) and use this information to assess the bipolar see-saw mechanism for abrupt climate changes. Students are encouraged to read two journal articles for more information and to synthesize their results with other information from lectures and earlier readings.
Determining whether students have met the goals
This lab is assessed using a simple rubric prepared for each question.
More information about assessment tools and techniques.
Teaching materials and tips
Activity Description/Assignment: Paleoclimate Homework (Acrobat (PDF) 200kB May18 10)
Ahn, J. and E.J. Brook. 2008. Atmospheric CO2 and Climate on Millennial Time Scales During the Last Glacial Period. Science, 322, 83-85.
Blunier, T., and Brook, E.J. 2001. Timing of millennial-scale climate change in Antarctica and Greenland during the last glacial period. Science, 291, 109-112.