Economics: Sea level rise

Summary

This module is framed from the perspective of a city planner trying to determine how much to spend on a local seawall given different scenarios of sea level rise and the associated storm surge and higher flood levels that come with it due to polar ice melt. Students refer to Climate Central's Risk Finder website for data on the probability of flooding under four different sea level rise scenarios. Combined with data on the number of homes affected under different flood levels, students calculate and graph marginal expected damage curves to make a recommendation on building a seawall based on marginal benefits and costs. The module can be easily tailored to various coastal regions based on the Climate Central's Risk Finder website.

Learning Goals

1. Increase climate literacy by connecting sea level rise due to ice melt in the polar regions to the local impacts of higher flood levels.
2. Learn tools to apply to decision-making given uncertainty in sea level rise and flooding.
3. Gain computational skills through calculating and graphing marginal damage curves in Excel.

Context for Use

This module has been used in a variety of undergraduate intermediate and introductory economics courses and an upper level interdisciplinary course with no economics pre-requisite. Class sizes ranged from 12 to 40 students. The module uses both PowerPoint slides to guide the students through the analysis and an Excel spreadsheet for making calculations and graphing. Some basic economic concepts are required (e.g. marginal benefits and marginal costs) but these concepts could be covered in class prior to starting the module.

The module contains three parts that can be completed in class over two shorter class periods (~50 min) or one longer class (~80+ min). The module can also be shortened at the instructor's discretion. Students also complete the introduction to the module before coming to class, which takes about 1 hour or less.

Description and Teaching Materials

Outline of Module

• Introduction to Module
• Part I: Estimating Marginal Damage Costs from Flooding
• Part II: Graphing Expected Marginal Damage Curves
• Part III: Making Decisions Under Uncertainty
• Discussion Questions
• Follow-up Assignment Prompt

Workflow of module

1. The instructor assigns the pre-class introduction to students found at the beginning of the Sea Level Rise module (PowerPoint 2007 (.pptx) 24.1MB Apr5 20), to be completed as homework before starting the module in class. This PowerPoint includes links to an article and video on polar ice melt.
2. The instructor gives a brief Sea level rise presentation (PowerPoint 2007 (.pptx) 3.2MB Mar16 20) given extreme polar ice melt, highlighting the connection between polar ice melt and the flood scenarios students will explore.
3. For shorter class periods (~50 minutes), students can work through Parts I and II of the Sea Level Rise module (PowerPoint 2007 (.pptx) 24.1MB Apr5 20). For longer classes, the students should be able to also work on Part III of the module. Student will also use the accompanying spreadsheet for sea level rise in Tacoma, WA (Excel 2007 (.xlsx) 37kB Apr5 20), or, the instructor can select a different coastal location to analyze by modifying the spreadsheet for regional sea level rise (Excel 2007 (.xlsx) 36kB Apr28 20).
4. Students are encouraged to work in pairs or small groups and are prompted to answer "Pause for Analysis" questions included throughout the Powerpoint slides in the module.
5. For shorter class periods, 5-10 minutes before class is over, the instructor brings the group back together and leads a discussions on selected Pause for Analysis questions. Then the instructor can either assign Part III of the module as homework, or have students complete it at the beginning of the following class period.
6. The instructor wraps up the module with a discussion on the assumptions and limitations of the analysis based on the suggested discussion questions at the end of the module in the Powerpoint. The instructor can refer to the Guide for Pause for Analysis and Discussion Questions.
7. The instructor has the option of assigning a memo assignment synthesizing the results of the analysis to a local city planned included at the end of the PowerPoint.

Teaching Notes and Tips

For more details on implementing the module in class, see the paper:

Fortmann, L. Beaudoin, J., Rajbhandari, I., Wright, A., Neshyba, S., and Rowe, P. (2019). Teaching Modules for Estimating Climate Change Impacts in Economics Courses using Computational Guided Inquiry. Journal of Economic Education. 51(2).

Assessment

Assessment of the module largely takes place during class time as the instructor walks around helping students work through the module. Additionally, class discussions on the Pause for Analysis and Discussion Questions at the end of the module allow the instructor to gauge student learning and highlight the key takeaways.

A follow up assignment prompt is also included, which entails the students writing a memo to a local city official that synthesizes their analysis and provides recommendations for addressing rising sea levels based on the marginal benefits and costs of building a sea wall based on their results.

References and Resources

Climate Central. Surging Seas Risk Finder Website: https://riskfinder.climatecentral.org/

Hauer, M. E., J. M. Evans, and D R. Mishra. (2016). Millions projected to be at risk from sea-level rise in the continental United States. Nature Climate Change.

Hudson, T., Keating, K., and Pettit, A. (2015). Cost estimation for coastal protection – summary of evidence. Environmental Agency. Report –SC080039/R7

IPCC (2013): Summary for Policymakers. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA.

Kopp, R. E., R.M. Horton, C.M. Little, J.X. Mitrovica, M. Oppenheimer, D.J. Rasmussen, B. Strauss, C. Tebaldi. (2014). Probabilistic 21st and 22nd century sea-level projections at a global network of tide-gauge sites. Earth's Future, 2(8), 383-406.