Why Extreme Heat Demands a New Health and Justice Lens

04 January 2026

Extreme heat in winter: why Copenhagen mattered

In the depths of a Scandinavian winter, extreme heat may be the last thing on your mind. Yet from 9–12 December 2025, heatwaves were at the centre of discussions at the Global Health Symposium on Extreme Heat and Health in the Context of Climate Change hosted by the School of Global Health and the Copenhagen Center for Disaster Research (COPE), University of Copenhagen, with support from the Novo Nordisk Foundation. The symposium brought together a diverse group of health researchers, humanitarian practitioners, climate, social and political scientists, economists, epidemiologists and journalists. Importantly, it also made a concerted effort to platform scholars and practitioners from regions most affected by extreme heat, while foregrounding the work of early-career researchers. I was invited to deliver a keynote address, alongside award-winning journalist, Laurie Goering who reports extensively on the impacts of extreme heat. Together, we opened the symposium with an interactive workshop , setting the tone for a series of rich, cross-disciplinary conversations.

Extreme heat as a growing global health threat

Extreme heat is rapidly emerging as one of the most serious public health consequences of climate change. A key takeaway from the symposium was that our understanding of how heat affects health, particularly among socially vulnerable groups, is still evolving. While heat is often treated as a short-term meteorological hazard, chronic exposure to high temperatures is increasingly linked to health conditions that remain under-researched and poorly understood. As climate change intensifies, the health burden of heat is likely to rise sharply, yet evidence, policy and preparedness are lagging behind.

Heat is lived, social and deeply unequal

Although extreme heat is shaped by atmospheric conditions, it is experienced through social realities. Heat is lived in homes that trap warmth, in informal settlements with limited access to cooling, in workplaces without adequate protection, and on streets where people have little choice but to remain exposed.

Understanding heat as a lived, social and unequal phenomenon is critical. Its impacts are shaped by gender, income, housing, labour conditions, health status and access to care. Without this lens, key risks – and opportunities for action – remain invisible.

Keynote reflections: biosocial heat and gendered risk

My keynote, Extreme Heat and Health in a Changing Climate: Biosocial Frontiers, Gendered Vulnerabilities and Pathways for Just Adaptation, focused on the need to understand heat as both a biophysical and biosocial process. Drawing on my research from cities across South Asia and Africa, I emphasised that intersectionality must be central to how we approach heat-related health risks. Gender, for instance, shapes exposure, care responsibilities, occupational risk and access to resources, yet remains insufficiently integrated into heat policy and planning.

I also highlighted insights from:

The International Institute for Environment and Development (IIED), work on informal settlements, indoor overheating and gender
Research on (in)habitability and the politics of heat in South Asian cities at the Karachi Urban Lab
HeatNexus which brings together nine innovative research projects to address the health impacts of extreme heat through collaborative and justice-oriented adaptation strategies

Prof Nausheen Anwar presents a key note speech at the Global Health Symposium on Extreme Heat and Health in the Context of Climate Change, Copenhagen

Learning across disciplines: why collaboration matters

One of the symposium’s greatest strengths was its emphasis on interdisciplinary knowledge sharing. Presentations ranged from research advocating for garment workers’ protection across South Asia, to new approaches for communicating heat risk through simplified early warning systems. Particularly striking were studies focusing on groups with little or no ability to avoid heat exposure, including people experiencing homelessness and precarious workers such as couriers in the gig economy. These contributions underscored how difficult—but essential—it is to research and respond to heat risks among over-exposed populations. Such work demonstrates that no single discipline can capture the full picture of extreme heat. Health outcomes, labour conditions, urban design, communication, governance and social inequality are deeply interconnected.

An example of interdisciplinary knowledge sharing was a thought provoking presentation by Cara Schulte, a doctoral candidate on climate and health and whose heat research advocates to protect garment workers across South Asia, as well as a presentation by Caroline Pereria Marghidan – PhD researcher on heatwave early warning systems – who presented a new framework that translates wet-bulb globe temperature (WGBT) into a simple 1-10 ‘heat force’ scale to support clearer heat communication. I don’t have the space to mention many other excellent presentations but a speaker who caught my attention was Giovana Faleiro who presented her MSc research on the impacts of extreme heat on homeless people in Rio de Janeiro.

Beyond quick fixes: the need for coordination and care

Another clear message from the symposium was the need for stronger coordination between regulators, policymakers, scientists and practitioners. Before prescribing solutions, there is a pressing need to collectively understand local contexts and lived realities. Spaces like this symposium may feel modest in scale, but they can be game-changers when they push the field beyond silos and disciplinary comfort zones, fostering dialogue that leads to more just and effective responses.

Why Heat Nexus matters

Extreme heat represents a severely uneven and underestimated burden of the climate crisis. It is already eroding health and wellbeing, exacerbating risks to maternal health, occupational safety and the management of chronic conditions such as diabetes. Those living in poverty, informal settlements and displacement-affected contexts are hit hardest—yet heat action plans and protective policies continue to lag behind rising risks. This is where initiatives like HeatNexus play a crucial role: connecting research, practice and policy to support collaborative, equity-focused adaptation. As heat-related morbidity and mortality rise, treating extreme heat as merely a climate or weather issue is no longer tenable. It is a public health and justice challenge—and addressing it requires interdisciplinary knowledge, political will and sustained attention to those most affected.