Teaching chemistry in the context of climate science

There is little disagreement in the scientific community that anthropogenic activity is the dominant cause of climate change. Climate change has been recognised as one of the basic planetary boundaries – the safe limits within which the Earth’s environment can self-regulate that could lead Earth’s systems being transformed into a new and altered state, should the threshold be substantially and irreversibly breached.

Scientists and economists are worried about the catastrophic effects that a rise in atmospheric temperatures would have on the value of the world’s manageable stock of social and capital assets. It is also recognised that poor and the marginalised segments of society will be those greatest affected and will bear a disproportionate burden of climate change.

Climate literacy principles can be readily mapped to chemistry

Academic institutes are expected to play a key role in addressing the problem of climate change, one of the most pressing and daunting challenges of the UN Sustainable Development Goals (SDGs). Climate science is complex and any solution requires systems thinking, which draws heavily on the intersection of physical and chemical sciences, earth sciences and social sciences. The centrality of chemistry, with its unique interface with physics, biology and the earth sciences, is expected to play a key role in addressing the challenges related to climate change, especially in areas like environment, population, waste management, health, water and energy. However, an understanding of the science of climate change and its links to chemistry is hardly addressed in the conventional chemistry curriculum in India.

Chemistry education

In our experience, many students who enter an institution of higher learning in India find chemistry irrelevant, uninteresting and indigestible. While some of the dissatisfaction can be reversed by a pedagogy that relies on building fundamental concepts rather than excessive demands on student working memory, the learning outcome for many students remains poor. Unfortunately, the pedagogy of chemistry teaching has not changed significantly in the last four to five decades. Additionally, in recent years, chemistry has also suffered from adverse media coverage and negative public perceptions.

One proposal that merits serious consideration is that chemistry must be taught in a way that conveys its contextual relevance to society. This means showing how chemistry meets regional and global sustainability challenges, and its position within a systems perspective framework that includes physical, biological, environmental and other systems. Climate science provides an extraordinary global context to facilitate student engagement with chemistry and interdisciplinary science concepts through a systems perspective. It allows the teachers to develop an innovative curriculum that also includes a robust understanding of fundamental overarching chemistry principles and themes, with assessable learning outcomes.

Climate change in the core curriculum

Several undergraduate chemistry curricula in India rely on the atom-first approach, in which the curriculum builds up the electronic structure of atoms and molecules as a means to explain and rationalise chemical reactions. This approach has been shown to result in better learning outcomes in comparison to traditional descriptive chemistry teaching. However, the teaching still relies heavily on the classical verticals of physical, inorganic, analytical and organic chemistry and, therefore, remains a ‘disjointed trot through a host of unrelated topics’.¹

Teaching chemistry though the context of sustainability allows us to bring a holistic approach

More recently, it has been advocated that teaching chemistry under the broad domains of structure, dynamics, function and reactivity will allow students to see the discipline of chemistry as an integrated science and not as fragmented verticals. In this background, we believe that using the context of climate science to teach the basics of chemistry will further integrate chemistry with other branches of physical and life sciences.

For example, when the electronic structure of molecules H₂, N₂, O₂, NO_x, and CO₂ is taught, the molecules’ physical properties are explained in the context of the kinetic theory of gases, their reactivities are taught using principles of thermodynamics and quantum theory and their interaction with light is discussed while teaching spectroscopy. However, these could be collected under the context of gases that support life directly, and those that support life by regulating the energy balance of our planet. This would allow a discussion on how electronic structures and a molecule’s interaction with the electromagnetic spectrum explains its role as, for example, a greenhouse gas. This can serve as the background to expand on topics related to the effect of greenhouse gases on our changing climate.

Climate literacy principles can be readily mapped to chemistry principles such as isotopes, gases, acids and bases, thermodynamics and thermochemistry.⁴ However, we should also take care to ensure that while introducing this approach we do not cause a substantial reduction of important domain content, which is pointed out by critics of this approach.

Climate change can be introduced as a 3–6-hour module in senior undergraduate courses like Sustainable Chemistry (or Green Chemistry), as is taught by the authors at IISER Kolkata.⁵ This module discusses the global carbon cycle vis-à-vis natural and anthropogenic processes, and it introduces the concept of net zero and the contribution of chemical processes to the 50 billion tonnes of atmospheric CO₂ that is being generated each year. The principles of life-cycle-analysis, especially being able to quantitatively determine the global warming potential (GWP) of a chemical process, has a big impact on students. For example, students can be asked to do carry out LCA on ammonia production and evaluate the step which contributes most to the GWP. This allows us to explore how such processes could be modified in the future to reduce their impact on the environment. Such quantitative analysis seems to improve the learning outcomes of our students.

Teaching chemistry though the context of sustainability in general and climate science in particular allows us to use this global context to bring a holistic approach in chemistry education, which we believe is the need of the hour. Unless sustainability and SDG are deeply embedded in the teaching and practice of chemistry, we may not be able to rescue chemistry from its fragile public perception and attract future generations of bright students to the science that is so vital to addressing the challenges of sustainability.