Mapping Coastal Vulnerability to Sea-Level Rise at Point Reyes National Seashore
This material is replicated on a number of sites as part of the SERC Pedagogic Service Project
In this Spreadsheet Across the Curriculum module, students work through the coastal vulnerability index and its application to the coastline at Point Reyes National Park as described in an online USGS Open File Report. That study divided the shoreline into ~1.5-km quadrangles and evaluated six coastal vulnerability factors on a scale of 1 to 5 at each quadrangle. The vulnerability factors include three geology factors and three process factors. The former three are: "geomorphology" (relating to resistance to erosion), history of accretion/erosion, and the slope of the coastal profile. The latter three are: rate of sea-level rise, wave exposure, and tidal range. The index is calculated by aggregating the six scores. Students reproduce the calculation by using a color-coded, conditional-formatted spreadsheet laid out on spreadsheet grid to simulate a map of the Point Reyes shoreline. The quantitative literacy point of the module is the use of scores based on ordinal scales.
This material is based upon work supported by the National Science Foundation under Grant Number NSF DUE-0836566. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.
- Examine real data related to relative sea-level change for different areas of the Californian coast including Point Reyes National Seashore.
- Map each of the ratings of the six vulnerability factors in the 64 shoreline cells of an Excel grid (one-minute squares) using conditional formatting so that cells with high ratings (hot colors) stand out.
- Average the six ratings cell by cell to produce a seventh map and color code it to show the distribution of average vulnerability scores around the shoreline.
- Rank the 64 averages in order to count the number of shoreline cells in each color.
- Calculate and map a different sort of "average," namely the USGS coastal vulnerability index (CVI), which is the square root of the product of the six individual scores.
- Rank the 64 CVI scores and compare the results for the CVI vs. the straightforward average.
- Read background information on Point Reyes National Seashore and sea-level rise, including graphs of sea level vs. time from California tide gauges from NOAA's National Water-Level Observation Network.
In the process the students will:
- Know that sea level is rising, it's rate, and why.
- Describe what controls how a shoreline responds to sea-level rise.
- Describe how the U.S. Geological Survey's coastal vulnerability index is calculated.
- Know what a minute is in terms of kilometers, longitude, and latitude.
- Describe how a quantitative ranking scheme is set up and carried out.
Context for Use
Description and Teaching Materials
The module is a PowerPoint presentation with embedded spreadsheets. Click on the link below to download a copy of the module.
PowerPointSSACgnp.GB450.LV1.8 (PowerPoint 7.3MB Jun1 13)
Optimal results are achieved with Microsoft Office 2007 or later; the module will function in earlier versions with slight cosmetic compromises. If the embedded spreadsheets are not visible, save the PowerPoint file to disk and open it from there.
The above PowerPoint presentation file is the student version of the module. It includes a template for students to use to complete the spreadsheet(s) and answer the end-of-module questions, and then turn in for grading.
An instructor version is available by request. The instructor version includes the completed spreadsheet. Send your request to Len Vacher (email@example.com) by filling out and submitting the Instructor Module Request Form.
Teaching Notes and Tips
The module is constructed to be a stand-alone resource. It can be used as a homework assignment, lab activity, or as the basis of an interactive classroom activity. It was used as an out-of-class activity in a senior-elective course, Environmental Geology of the National Parks (for geology majors and nonmajors), during development of the module in Spring 2010, and as an out-of-class activity in Computational Geology (a QL course for geology majors) in Fall 2010 and Fall 2011. In general, the students considered this module to be one of the more elementary modules in the collection. It is now one of the modules that is rotated into the online introductory-level Geology of National Parks course.
There is a slide at the end of the presentation that contains end-of-module questions. The end-of-module questions can be used to examine student understanding and learning gains from the module. Pre/post test, pre/post test answer key, and answer key for end-of-module questions are at the end of the instructor version of the module.
References and Resources
US National Park Service (NPS)
Point Reyes National Seashore
Tides and Currents Website of the Center for Operational Oceanographic Products and Services (CO-OPS)
Linear mean sea level (MSL) trends and 95% confidence intervals in mm/yr
National, Regional, and Global Maps: Sealevel Online
National Water Level Observation Network (NWLON)
Impact to California's coast of a 1.4-m sea-level rise
Coastal Vulnerability Assessment of Point Reyes National Seashore (PORE) to Sea-Level Riseby Pendleton, Thieler and Williams
California Coastal Records Project
California Coastal Records Project: Point Reyes Lighthouse
Coastal Vulnerability Assessment of Point Reyes National Seashore (PORE) To Sea-Level Rise: U.S. Geological Survey Open-File Report 2005-1059
NPS: Rising Sea Levels Endanger Point Reyes Beaches. Conclusions the NPS drew from the study.
Map of the CVI produced by the USGS.