Floods over time: death vs. destruction
In this lab exercise, students investigate trends of lives and dollars lost in the United States due to major floods during 1900-1979. With a given dataset (see page 48 in USGS paper at link), they calculate flood losses in both dollars and loss of human life by decade, and graph their results. Students then analyze their graphs by comparing the two trends. The are asked to establish reasons for each trend, using information provided in lecture about population and socioeconomic change, and flood prevention, prediction and mitigation efforts in each of the decades graphed.
This lab is designed to:
- give students experience in data analysis and evaluation.
- provide a means of allowing students practice in applying information conveyed in lectures to real-life data.
- develop students' critical analysis of information and arguments (they must decide what is relevant to the posed question).
- to enhance students' writing through persuasive argument.
Context for Use
This exercise takes approximately one to one and a half hours. It could also be used as a take-home assignment.
The lab is designed for an introductory level course at a business school with no science majors. Therefore, a significant amount of other (non-geology) information - such as the financial aspect of natural disasters - is presented in lectures.
Before administering this exercise, students must be familiar with the interplay of disasters and population (or should be able to derive that relationship!), and must have already received background lectures about flooding - prevention, forecasting, mitigation, etc.
Description and Teaching Materials
Lab exercise is self-contained in terms of data, etc.
Calculators and colored pencils - or computers - are needed to perform arithmetic and to plot data by hand. (I prefer having students do this exercise by hand, but if computers are allowed, data (not available as an Excel file) may be downloaded as a professional paper: https://pubs.er.usgs.gov/publication/pp1240B . The appropriate table is on pg. 48 in the online version of publication.)
Lab handout: Floods over time: death vs. destruction (Microsoft Word 82kB Jun26 06)
Teaching Notes and Tips
Students often have difficulty plotting data on the chart I made up for this exercise, as many of them have never seen an x-y-y plots. A short tutorial on how to make/read this type of plot may be in order.
I have had some difficulty in getting students to truly be able to grasp the intricacies of the interrelationships between:
- economics and dollar losses (this is a bit of critical skepticism, as the losses are not adjusted for inflation!); and
- flood prediction and prevention and why that means greater dollar losses but fewer deaths. (The simple statement, "You can move a body but you can't move a house" is the best I have heard!)
I grade this assignment based on getting the charts and overarching trends identified, and then on how detailed the responses to questions are. Do they cover (and explain!) the results of flood prediction, for example, as both something that will not change dollar losses, but will allow for evacuation? That flood prevention measures act as "false security," allowing more people to believe themselves protected from floods, and therefore more prone to build on floodplains?(Etc...)
References and Resources
Among numerous resources, these are some of these general sites I like to use and suggest students look around at the various pages within them:
- Teaching floods and flooding quantitatively
(basic, general info)
(recent shorter, brochure-style version of above)