Sustainability Metrics

Natalie D Hunt, University of Minnesota-Twin Cities
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Sustainability is a complex term applied to many different contexts in a variety of ways. As a result, it can be challenging to determine how sustainable something really is. In this module, students will use an analytical framework with publicly available data to formulate questions, analyze data, and report metrics of sustainability.

Strengths of Module

This module allows students to interact with real-world data to identify, quantify, and visualize metrics of sustainability. The breadth of available metrics is large, so exploring these datasets under an analytical IPAT (Environmental Impact is a function of Population, Affluence, and Technology) framework provides guidance and context for posing meaningful sustainability questions and answering them with quantitative data support. Students also develop quantitative reasoning skills by investigating an existing dataset interface and answering questions about data availability, sources, suitability, and units.

What does success look like

By the end of this module, students will be able to formulate questions about sustainability, navigate the Gapminder tool to find and incorporate multiple factors of quantitative data, read and interpret graphs, and report their findings, supported with quantitative data. Specifically, students will be able to:

  • identify data sources and units from the Gapminder online interactive data tool
  • read and interpret a bubble chart incorporating multiple factors of sustainability data
  • generate a time series bubble chart to track sustainability metrics over time
  • communicate their findings with the class and discuss the strengths and limitations of the IPAT framework

Context for Use

This module is intended for an upper-level undergraduate course in sustainability, environmental studies, systems thinking, natural resources consumption, or any interdisciplinary course that includes these concepts. Students are expected to be familiar with the three facets of sustainability and to have some experience with reading and interpreting graphs.

This module is designed to be implemented in two 1.25-hour classroom sessions, but could be adapted to be completed in one 2.5 - 3 hour lab session. The module requires a laptop or desktop computer or tablet with internet access.

Description and Teaching Materials

Why this Matters:

Sustainability is a complex term applied to many different contexts in a variety of ways, which can lead to confusion over meaningful assessment. The Brundtland Commission defined sustainability as 'the ability to meet one's own needs without jeopardizing the ability of future generations to meet their needs.' It is characterized by considering environmental, economic, and social factors. A commonly used analytical framework, "IPAT," is used to link metrics of sustainability to broader facets of economic, environmental, and social sustainability.

Impact = Population x Affluence x Technology

The Gapminder foundation is an independent institution that provides data and education resources on numerous global-scale topics. They built a series of online interactive data tools where users can access and visualize numerous datasets on global issues. Here is an introduction to the Gapminder toolkit.

Within the Gapminder tools, Impact can be described using metrics such as greenhouse gas emissions, air pollutant emissions, or freshwater extraction rates. Affluence is typically measured by per-capita Gross Domestic Product (GDP), measured in Purchasing Power Parity (PPP). Metrics for assessing technology could include fossil energy production, energy consumption, extent of communication infrastructure, among others. The objective of this module is to illustrate the three specific facets of sustainability (economic, environmental, and social) using real-world data and metrics under the IPAT analytical framework.

Quick outline/overview of the activities in this module:

  • Pre-module work: Students are assigned the Mattick et al., 2010 reading and must complete a Pre-Assessment Tool prior to the first lecture session.
  • Activity A: Students learn to navigate the Gapminder tool, identify components of a graph, and interpret a graph under the IPAT analytical framework.
  • Activity B: Students explore sustainability metrics by framing a sustainability question, building a graph, interpreting results, and communicating findings with peers.
  • Activity C: Students formulate their own question about sustainability, download datasets from the Gapminder Tool website, compare and contrast sustainability metrics for a specific country over time, and reflect on strengths and limitations of datasets and IPAT framework for quantifying sustainability.

Pre-module work

Students are assigned the Historical Trends in Global Energy Consumption paper and asked to complete an online

(note: the answers are included in this file) prior to class. The online assessment will address the three facets of Sustainability, the IPAT analytical framework, specific terminology, and the student's ability to read and interpret a graph. Students can retake the assessment until they receive a 100% score.

Activity A

Students will be given a Student Guide handout (Microsoft Word 2007 (.docx) 39kB Jul24 20) with step-by-step instructions for this activity, which will be completed individually. There are assessment and reflection questions throughout, and students turn in their completed handout at the end of this activity.

For this activity, students are guided through the steps to generate a graph of CO2 emissions, energy usage, population, and income (GDP) in the Gapminder tool interface. The countries will be broken out into income classifications of High, Upper Middle, Lower Middle, and Low Income, and will be displayed showing the population of each. Students will identify the components of the graph, cite the data sources, and describe the units used.

Students will describe the relationship between x-axis and y-axis metrics, identify any outliers, and draw conclusions about these sustainability metrics relative to the IPAT framework. The instructor and/or the teaching assistant can assess student progress by circulating around the room and informally asking questions, checking work on the student handout, and providing feedback.

Activity B

Students work in pairs to explore data and plot graphs using the Gapminder tool. They will identify available environmental (e.g. CO2 emissions, PM2.5 emissions, freshwater consumption, etc...) and technological (e.g. fossil energy production, energy, or communication infrastructure) metrics underlying the IPAT framework, and use them to frame a sustainability question. Students will then plot the relevant data with the selected Impact metric on the y-axis and the selected Technology metric on the x-axis. Gapminder classifies countries into economic levels (High, Upper Middle, Lower Middle, Low Income), and students will be asked to select one country from each economic level and describe the economic, environmental, population, and technological metrics from each of the countries.

Students will then discuss and answer a series of questions about whether their findings support their sustainability question and the relationships among IPAT metrics for countries of differing economic status, and reflect upon the strengths and limitations of the IPAT framework in quantifying sustainability. Students will turn in a screen grab of their graphs along with their responses.

Activity C

The IPAT framework is not a perfect predictor of impact, but rather a framework for thinking broadly about the relationships among impact, population, affluence, and technology. Not every country will fall neatly under this framework, due to the multiple factors that influence sustainability, or the variation in each country's socioeconomic history. This is one of the challenges in quantifying sustainability. Additionally, sometimes impacts are not fully captured in datasets due to limitations in collection, processing, or access.

Such datasets highlight the importance of using metrics to support sustainability claims, so that decisions can be made based on scientific evidence. One of the powerful features of the GapMinder tools is that users can visualize data over a specific time frame to explore how sustainability metrics change over time.

For Activity C, students will look at the factors that informed their initial sustainability question over time. Using the same metrics they explored in Activity B, students will be asked to rebuild the graph in Gapminder tools with a specific focus on how those metrics may have changed over time.

Students will be asked to select four countries across the different economic levels (e.g. High, Upper middle, Lower middle, and Low) to track over time. They will answer questions about observed data trends and will discuss interpretations and potential drivers of those trends. They will also reflect upon real-world events that may have influenced the observed data trends and whether the IPAT framework can capture such events. Students will then submit a screen grab of their graphs along with the responses to their questions.

Teaching Materials:

  • : Step-by step instructions for the activities, with responses and teaching notes in green.
  • Student Guide (Microsoft Word 2007 (.docx) 39kB Jul24 20): Step-by-step instructions for the activities.
  • (note: answers are included and should be removed before giving to students)
  • Gapminder Tools Instructional Video (hosted on Vimeo)

Teaching Notes and Tips

This module is designed to be conducted in consecutive order, as each activity builds on the one before. The module could be modified for an entirely online format, with student pairs communicating over a video conferencing platform.

Workflow of this module:

  1. Assign pre-class readings and . The assessment tool can be deployed online or as homework prior to the class.
  2. Give students the student guide handout (Microsoft Word 2007 (.docx) 39kB Jul24 20) when they arrive to class.
  3. Instructor may give brief a PowerPoint presentation (not provided) introducing the GapMinder tools dataset. Discussion of the reading and pre-assessment tool can be integrated into this presentation or done before.
  4. Students then work through the module activities. Any unfinished content on Day 1 can be saved for Day 2.
  5. Student groups can present their findings to the whole class following completion.

Notes on the student handout:

Potential pre-class readings:

Measures of Student Success

Student success is demonstrated as:

  • Students are able to identify metrics appropriate for IPAT framework, their respective units, and sources via the Gapminder tools.
  • Students are able to generate a bubble graph incorporating an Impact metric on the y-axis and a Technology metric on the x-axis, and display the countries according to economic level and population via the Gapminder tools.
  • Students are able to compare and contrast the IPAT relationship across different countries of varying economic scale and identify the metrics that hold up those metrics using Gapminder visualization tools.
  • Students can characterize and compare country-level Impact based on PAT by using summary statistics (e.g. mean population, mean per-capita GDP, mean per-capita CO2 emissions).
  • Students are able to identify patterns across countries, outliers (address the open-ended nature of the question), and are able to formulate hypotheses around why IPAT may not hold universally.

References and Resources