Mathematical thinking can drive solutions for climate, energy and many other development issues Nalini Joshi is Payne-Scott Professor of Applied Mathematics at the University of Sydney, a member-at-large of the Executive Committee of the International Mathematical Union, a member of the International Science Council Governing Board, and a fellow of the Australian Academy of Science How are you concerned with sustainability in your work? Nalini Joshi: I don’t work directly on sustainability because my research focuses on theoretical developments in dynamical systems, systems that evolve over time. These models have potential applications in areas like climate systems, but my work itself is not specifically aimed at sustainability. How do you feel mathematicians could contribute to sustainability? N.J.: Mathematically trained people can help in many ways. Let me take the example of my colleague John Boland, from the University of South Australia, who modeled the integration of renewable energy sources like solar and wind into the Australian electricity grid. Early on, people worried that fluctuations in wind or sun would cause unstable energy supply, but his modeling showed how to manage this using topography, location data, and time-series analysis. His work with mathematics also supported thermal efficiency studies for housing, optimization of renewable energy incentives, and analysis of energy market fluctuations. Skills like optimization, data analysis, network modeling, and AI-based trend detection are essential. What other areas of sustainability benefit from applied mathematics? N.J.: Many. Some colleagues model river flows, tidal changes, and flood risks as climate change alters water levels. Others work on bushfire modeling, integrating indigenous knowledge on land management. Applied mathematicians also study urban heat effects, resource allocation, and environmental risks. What should mathematicians focus on to support sustainable development? N.J.: The best progress happens when mathematicians collaborate with specialists from other fields, like engineers, grid operators, or policymakers. In Australia, events called Mathematics in Industry Study Group bring companies and mathematicians together to solve real-world problems in one intensive week. Such initiatives could be expanded internationally to address sustainability challenges. Some mathematicians focus on very theoretical research. How could they be engaged in sustainability work? N.J.: Theoretical mathematicians often pivot to applied problems through personal connections. When they have opportunities to engage with others, collaborations can arise. For example, in the past, algebraic geometers contributed to cryptography; topologists developed topological data analysis to detect gaps in datasets, that have been applied for instance to improve CCTV coverage in urban areas. Creating opportunities for interaction is key. When people meet, share problems, and see the urgency, theory and practice can merge naturally. How could the International Mathematical Union promote such collaboration? N.J.: The International Congress of Mathematicians, held every four years, could host a panel on sustainability. This would engage younger researchers and highlight urgent global challenges. Moreover, the IMU’s Commission for Developing Countries could support training and research in regions facing severe climate impacts. Partnerships with organizations like the UN or foundations might provide funding. What would motivate mathematicians to engage with sustainability? N.J.: History shows that mathematicians mobilize when urgency is clear: think for instance of the deciphering of the Enigma German coding machine during World War II. If we raise awareness about the environmental crisis as a pressing, shared threat, mathematicians will step up with creativity and commitment. Interview by Luc Allemand SUBSCRIBE TO OUR NEWSLETTER To stay up to date with our projects and the development of the EHC Read more articles

Geographer Kathryn Yusoff explains why traditional disciplines and Western frameworks fail to address environmental crises, calling for transdisciplinary, decolonial approaches to planetary repair

From obligatory sustainability courses to international collaborations, the new Luxembourg Centre for Socio-Environmental Systems is rethinking how a research centre can contribute to the very diverse dimensions of sustainable development Ralf Seppelt is the Director of the Luxembourg Centre for Socio-Environmental Systems (LCSES) at the University of Luxembourg What is the purpose of the newly founded Luxembourg Centre for Socio-Environmental Systems (LCSES)? Ralf Seppelt: Humanity most likely will fail achieving the United Nations Sustainability Development Goals by 2030. The main reasons, from the latest assessment by the Intergovernmental Platform for Biodiversity and Ecosystem Services (IPBES), is because we do not understand the interconnectedness of the various indicators and the various fields of sustainability. So, our idea is to focus on this interconnectedness and see where synergies and tradeoffs are, applying various measures. Global resources, clear atmosphere, clean water, ecosystem functioning, are common pool resources. To me, humanity does not understand on a global scale how to deal with common pool resources. Why did the University of Luxembourg decide to create such a centre now? R. S.: The University has three strategic priorities: digitalization, medicine and health, and sustainability. Up to now, sustainability efforts here were mainly oriented toward finance and health. What was missing was a strong environmental science component — and that’s what LCSES will deliver. The government and the University’s Board of Governors pushed for this initiative. We will also link up with various research institutions in Luxembourg, such as the Luxembourg Institute of Science and Technology, or the Luxembourg Institute of Health. There is an urgent need to increase sustainability literacy, both among students and in society. That is why we will introduce an obligatory sustainability course for all students — from engineers to future doctors — and expand outreach to policymakers and the public. So your mission is not just research but also education? R. S.: Exactly. As a research-focused institution, our primary goal is to generate knowledge. But equally important is building capacity: giving students, professionals, and decision-makers the understanding they need to act. How will LCSES be structured? R. S.: We will build up the centre on four more or less topical professorships: biodiversity, food security, global health and climate extremes. In addition, we will have professorships focusing on the economy and governance of global resources. To support interdisciplinary, even transdisciplinary, work with these people, we will have a synthesis centre, which is fostering exactly those projects, where there are resources for that. There are also resources for getting international colleagues and scholars working on these various research topics. At the same time, we do have a science policy group who is supposed to communicate these results and findings that we have, and not necessarily new findings, because there are lots of old findings which still have to be communicated to policymakers. And that is actually the team which will support IPCC, IPBES, the local government, and the EU Commission. How do you plan to foster collaboration within and beyond the University? R. S.: Our synthesis team will open every year calls for collaborative research on pressing sustainability issues — especially those that cut across different domains, like the links between pollinator decline, food security, and child nutrition. These synthesis projects will bring together experts from the University, our centre, and at least 50% of participants from outside Luxembourg. They will not just produce academic papers but policy-relevant insights. And as interdisciplinary work is challenging, we will provide facilitation and structured support. How will your work be evaluated? R. S.: The University undergoes an external evaluation every four years, looking at research, teaching, and outreach. We also have performance indicators such as publications, third-party funding, and societal impact. Importantly, the University and other organizations in Luxembourg, such as the National Research Fund, have signed the DORA Declaration on Research Assessment, which means that we request serious research, but that it is not evaluated through citations figures or H-index: the real content and impact are examined. Do you already plan to engage with international networks to develop your kind of work? R. S.: I try to link up with the European research centres or research institutions which are working in the same direction, in Edinburgh, London, Stockholm, Potsdam, Zurich, Vienna, etc. We will not necessarily build some formal network but at least exchange and be clear that we are working in the same direction rather than competing. How could a coalition like the Earth-Humanity Coalition support the goals of LCSES? R. S.: Two things stand out. First, communication: connecting people across disciplines and institutions who are working toward sustainability and creating a space for reflection on whether research is truly contributing to that goal. Second, internal feedback: helping research institutions, including ours, make their own practices more sustainable, from how we travel to how we publish. Finally, the coalition could amplify our policy engagement by connecting us to broader networks of decision-makers and stakeholders. Interview by Luc Allemand SUBSCRIBE TO OUR NEWSLETTER To stay up to date with our projects and the development of the EHC Read more articles

In Togo, the Association des Volontaires pour l’Environnement Sain supports local communities to solve environmental problems and develop sustainable economic activities The Togolese NGO Association of Volunteers for a Healthy Environment (AVES), whose executive director is Koku Selom Agbavito, organizes community works to restore the environment What are the goals of the Association des Volontaires pour l’Environnement Sain (AVES, Association of Volunteers for a Healthy Environment)? Koku Selom Agbavito: Although our name insists on environment, we are concerned with all aspects of sustainable development. In our activities, particularly our research and assessments for setting up projects, we find that, on the one hand, environmental issues are linked to economic and social problems and, on the other hand, when the natural environment is improved, this also has an impact on the economy and society. Furthermore, in order to find lasting solutions to environmental problems, we believe it is essential to understand the expertise of local communities and what they have to offer. Our work therefore focuses particularly on local skills and co-construction. Who are the members of the association and how has it evolved? K.S.A.: AVES was founded in 2005 by four young university students, including myself, who wanted to experiment and apply what we had learned at university to solve certain problems within our communities. Initially an association, we became a non-governmental organization because we provide services. We are based in the municipality of Kpalimé, in the south-west of Togo, near the border with Ghana, but we operate throughout the country. What does it involve? K.S.A.: We are active in territorial planning. For example, we help communities or villages to draw up their own development plans, which begins with an assessment to analyze the problems before identifying their potential. Based on this potential, we identify the strategic paths they can take. So, you are carrying out missions of general interest on behalf of the government or external agencies? K.S.A.: Yes, we apply to calls for expressions of interest for studies or services. We are also approached directly by villages, particularly for projects to restore degraded land, for which we put together the project, including seeking funding from donors, supporting policy decisions, and providing technical training. When you talk about , what exactly is “degraded land”, and what are the benefits of restoration? K.S.A.: Land can be degraded by various causes, such as overgrazing, excessive tree cutting or monoculture. Restoring this degraded land not only allows it to be brought back into cultivation, but also promotes biodiversity. This leads to significant economic and social development. For example, the return of biodiversity provides access to medicinal plants that had become rare or disappeared from the area, which is of particular interest to traditional practitioners. Could you give us a concrete example of a land restoration project and its economic benefits? K.S.A.: We carried out a restoration project where we reforested more than 82 hectares. Thanks to collaboration with a German university, we were able to use techniques to assess biodiversity growth via a geographic information system. Being able to accurately measure the size of plants, their growth rate, accumulated biomass, and carbon capture or emissions can open up access to the carbon credit market. The financial resources generated can then be reinvested to improve social conditions, for example by renovating or building schools. Who are your partners in Togo? K.S.A.: We support municipalities in implementing their municipal plans. We also work with volunteer-based networks to get students to participate in our programs on a voluntary basis, because selfless mutual aid is an important value in our country, and we strive to preserve it, even though the concept of volunteering without any ulterior motive of monetization is tending to disappear. We are also part of local consortia within thematic networks, which promotes exchanges between actors in the same area. You mentioned the importance of local skills and know-how. Do you have any examples where local practices are more effective than “modern” solutions brought in from outside? K.S.A.: Many projects funded by international aid have little or no impact because they are not adapted to local realities. For example, regarding seed conservation, United Nations programs have set up modern stores, but we have observed that seeds preservation rates are higher in traditional granaries, possibly with some improvements. This is a striking example of how communities have their own ways of doing things, and it is essential for harmonious development to value these before introducing new solutions. Furthermore, traditional granaries can vary from one community to another. Do you mean that practices differ from one region of Togo to another? K.S.A.: Yes, absolutely. Even among the Ewe people in southern Togo, there are smaller communities with slightly different practices in granaries building. In the mountainous region of Danyi, their technique is a little different from that in regions such as Atchavé or Tové, due to differences in humidity, for example, which require specific adaptations. What interest do you see in joining The Earth-Humanity Coalition? K.S.A.: My motivation is to share experiences and expertise. Exchange, case studies, and sharing experiences are essential to support our actions in the field: exchanging with actors from other regions on a topic where they may be more advanced is very enriching. I saw on The Earth-Humanity Coalition website that it already brings together a lot of expertise. Are you already part of any national or international networks? K.S.A.: Yes, at the international level, our NGO is accredited to the Climate Conference of the Parties (COP), where we participate when we can. We are also part of the Global Network of Civil Society Organisations for Disaster Reduction (GNDR), where we are the national focal point in Togo. We are also members of the Initiatives Climat (Climate Inititatives) network, based in Morocco. What needs are not covered by these networks that could be covered by EHC? K.S.A.: These networks are thematic. We want to remain open to all issues related to sustainable development, and EHC could offer us this diversity and

The Anthropocene Commons integrates art, education, and activism to address the challenges posed by the geological era where human activities have fundamentally changed the planet John Kim is a professor of media and cultural studies at McAllister College in Saint Paul, Minnesota, USA, and a member ot the Anthropocene Commons You are involved with the Anthropocene Commons. Could you tell us about this network? John Kim: The Anthropocene Commons is a network of researchers, educators, activists, artists and scientists worldwide. It was built through the work that has been done over the past 12 years initially by the Anthropocene Curriculum, an initiative supported by the Max Planck Institute of Geoanthropology, in Jena, Germany, and the Haus der Kulturen der Welt, in Berlin, Germany. It’s now run collectively by members of the network. One of its primary objectives is to explore and publicize the concept of the Anthropocene as a new geological epoch, in which human activities have fundamentally changed the planet. The Anthropocene Commons includes members of the Anthropocene Working Group, which has been tasked by the International Commission on Stratigraphy with gathering evidence to support this classification, to no avail so far. However, the Anthropocene Commons is much more interdisciplinary, incorporating art, education, and activism to address the challenges posed by the Anthropocene. How does it contribute to understanding this new geological epoch? J. K.: In my own work on the Anthropocene, I employ the concept as a way of thinking about local place-based challenges and forms of resistance to the Anthropocene in different geographical regions around the world. I myself started contributing to this initiative because of my previous work concerning the Mississippi River: I had been contacted to take part in a project named “Mississippi: An Anthropocene River” about exploring the Mississippi River as a site-specific concept of the Anthropocene. The project ran from 2019 to 2022 and involved research, art-making, and public engagement activities from the river’s headwaters, Lake Itasca in Minnesota, to the Gulf. The idea was to use the Anthropocene as a framework for understanding local environmental challenges and to inspire collective action. What was your previous work on Mississippi about? J. K.: A few public art projects that I had made before had a lot to do with the geological history of the Mississippi River. For instance, I had created a public art sculpture called “Meander“, which visualizes the geological history and current environmental quality of the Mississippi River. Another project, “Phase Change“, explored climate change’s impact on the Upper Midwest through an ice sculpture installation. Your work seems deeply intertwined with sustainability and environmental activism. How do you integrate these themes into your academic and artistic endeavors? J. K.: My work often sits at the intersection of media, art, and activism. I also incorporate these themes into my teaching, focusing on media activism and environmental awareness. I aim to engage students and the public in reimagining our relationship with the environment through cultural organizing, which goes beyond traditional activism. How does your approach to cultural organizing differ from traditional activism? J. K.: While activism often conjures images of protests, cultural organizing is broader. It includes various activities that bring people together, that could include public art, education, and varied forms of community engagement. For example, we’ve organized music festivals and educational camps that foster a sense of community and shared purpose. This approach allows for diverse forms of participation and highlights the role of art in organizing around environmental awareness. The Anthropocene Commons is a global network. How does it operate on such a scale, and what are its key activities? J. K.: The network operates by connecting individuals and organizations worldwide through collaborative projects, like the one I mentioned about Mississippi, and events. One of our important ongoing activities has been organizing Anthropocene Campuses, which are gatherings in global locations to explore local environmental challenges using the Anthropocene framework. For example, we organized a Campus in Brazil in 2023 and 2024, and we have upcoming campuses in Chicago, in 2025, and in Stockholm, in 2026. These events bring together diverse voices to foster interdisciplinary dialogue and action. Additionally, we engage in projects like the Mining conversations, webinars that examine the local and global impacts of resource extraction. Speaking of mining conversations, how do these discussions contribute to understanding and addressing the environmental impacts of mining? J. K.: The mining conversations aim to explore the global upscaling of mining activities, especially in the context of the green energy transition. We bring together representatives from different regions to discuss how mining affects their areas and to share strategies for addressing these challenges. The conversations are interdisciplinary, involving historians, activists, and artists to provide a comprehensive understanding of mining’s implications. This approach helps to raise awareness and inspire action at both local and global levels. What draws you to collaborate with The Earth-Humanity Coalition? J. K.: The Earth-Humanity Coalition shares a similar ethos of connecting and supporting organizations working on the periphery of environmental and social challenges. I’m drawn to its focus on amplifying the voices of frontline communities and addressing the nuanced politics of sustainability. The Earth-Humanity Coalition can be a dynamic place that can support and bring together people who offer varying perspectives on sustainability goals in order to open up necessary local perspectives that may not be clear to intergovernmental or governmental organizations that are fully invested in them. An organization like the Anthropocene Commons strives to represent such perspectives, ones that foreground how ongoing and renewed processes of colonization and resource extraction—even connected to sustainability goals—are having direct effects on the livability of the planet for human and non-human life. As I understand them, this is part of the work of the Anthropocene Campuses and Mining Conversations series that I spoke to earlier. Interview by Luc Allemand SUBSCRIBE TO OUR NEWSLETTER To stay up to date with our projects and the development of the EHC Read more articles