# Sustainable Mathematics

2019 has seen a series of strikes around the world demanding action against climate change began as part of Global Week for the Future. It inspired me to look into ways mathematics contributes to the growing challenge of sustainability. Sustainability is the ability of a system to meet the needs of the present generation without compromising the ability of future generations to meet their own needs.

One way we can use math for sustainability is to add it to our syllabus. If you are looking for ideas, the blog “Sustainability Math” by Dr. Thomas Pfaff (Ithaca College) has a collection of projects in statistics and calculus related to sustainability. Thomas Pfaff and Jason Hamilton expand on these ideas in the book “Mathematics for Social Justice: Resources for the College Classroom” by considering social justice and sustainability as the same system. They do this by discussing three sustainability issues: climate change, income inequality, and lead exposure and crime.

If you are a fan of differential equations like me, you can take a look the recent special issue of the CODEE Journal “Linking Differential Equations to Social Justice and Environmental Concerns”. It includes 11 ideas on how students can use applied mathematics to make a difference. Using mathematics to solve real-world problems in their differential equations classroom can shape student identities as Karen Kleen, Next CODEE Editor-in-Chief, shares,

“[The students] talked with me about working together on problems of population growth, and climate change, and other questions that involve finding answers to society’s and Earth’s issues. These students, who were all from underrepresented groups in STEM, showed how they are developing mathematical identities that includes being mathematical problem solvers to make a difference.” – Karen Allen Kleen

You can also share with your students the Society of Industrial and Applied Mathematics (SIAM) has a videos such as “Math Behind Sea Ice & Our Changing Planet” and “Renewable Electricity: Where are we now and where are we headed?” which explain in a few minutes how mathematicians contribute to global sustainability problems.

#### At conferences and for community building

A big concern in academic social media is the environmental impact of travel. In the opinion piece “Reducing the Carbon Footprint of Academic Travel”, 12 scholars offer concrete ideas on how lower the environmental impact of academic travel and suggest some questions for consideration when planning an event, such as

• Calculate the carbon impact of your event. What steps can you take to minimize that impact while achieving your goals?
• How might decarbonization improve your event — whether in terms of intellectual exchange, equity and inclusion, or some other factor?
• What goals for your event could be achieved by means other than an in-person meeting? How can your event make the most of its setting and the physical travel that it involves?

Some of the suggestions include minimizing the carbon impact of an event by serving vegetarian food, encouraging digital and not paper programs, minimizing swag and working with your venue to serve food and drink in reusable or compostable containers. Also, holding fewer conferences or minimizing overseas travel, organizing conferences at regional hubs near airports or as part of bigger conferences, and building carbon offsets into the conference budget.

These ideas extend to other aspects of academic life. For example, the use of virtual platforms (i.e. Skype, Zoom, Webex, Connect and GoToMeeting) to hold conferences, give talks remotely, and build communities through online discussion groups. There are several online communities such as Quantitative Undergraduate Biology Education and Synthesis (QUBES) Hub, SIMIODE, and SUBgroups which encourage collaboration, resource sharing, and building community.

#### The intersection of research and sustainability

In his 2013 opinion piece, “The Mathematics of Sustainability“, Simon Levin, identifies three mathematical challenges towards achieving sustainability: developing the statistical mechanics of ecological communities, socio-economic systems, and the biosphere, modeling the emergence of an ecological pattern, and determining indicators of impending critical transitions between states. He also points out the great challenge of achieving cooperation with problems at a global scale, especially in the case of common resources, and the mathematical theory needed to tackle it.

“The greatest challenge facing us is to achieve cooperation in dealing with problems of the Global Commons, especially as regards public goods and common pool resources. This brings to the fore a different set of mathematical tools—control theory, game theory, voting theory, and mechanism opinion design — for identifying under what conditions cooperation is possible and how best to achieve it.” – Simon Levin

Also, SIAM hosts the Conferences on Mathematics of Planet Earth (MPE) which looks to offer a forum for mathematicians and computational scientists to discuss planet earth as a physical system, which supports life, organized by humans, and is at risk. It will be held again in June 2020 and is co-located with the SIAM Conference on the Life Sciences. This conference is part of a larger initiative described in Evelyn Lamb’s post, “Strength in Numbers: Mathematicians Unite to Tackle Climate Change and Other Planetary Problems” whose goal is to “convince more mathematicians that climate change and other planetary problems are not only important but also interesting”. Besides, talk of “Green AI” has surged in the artificial intelligence community due to a recent paper by Roy Schwartz, Jesse Dodge, Noah A. Smith, and Oren Etzioni from the Allen Institute for AI. The ideas of the paper are summarized very nicely in Juan de Dios Santos’ blog post “Sorry, but your cat or dog AI is damaging the world”,

“The authors propose using efficiency, alongside accuracy and overall performance, as an evaluation metric for future AI implementations. Furthermore, the writers suggest that Green AI could turn the field into a more inclusive one. By doing so, not only researchers but students and others that don’t have access to state-of-the-art machines would have the opportunity to contribute to the field.”- Juan de Dios Santos

Big challenges need out-of-the-box thinking and a lot of collaboration. Be it in your classroom, research, or at your next conference, make sustainability part of the discussion.