The first ever Health Day at COP highlights the link between climate change and health

Efforts to recognise the relationship between health and climate change really came to the fore during the COVID-19 pandemic. This culminated in the first Health Day at any Conference of the Parties. The COP28 UAE Declaration on Climate & Health has been signed by 121 countries.
December 19, 2023

On the 3rd of December, we saw the first ever Health Day at COP

Health Day focused on five key topics:

1.   Showcasing evidence base and clear impact pathways between climate change and human health.

2.   Promoting "health arguments for climate action" and health co-benefits of mitigation.

3.   Highlighting needs, barriers, and best practices for strengthening climate resilience of health systems.

4.   Identifying and scaling adaptation measures to address the impacts of climate change on human health (including through One Health).

5.   Taking action at the nexus of health and relief, recovery and peace.[i] 

How is climate change linked to health?

The first way that climate change is connected to health is temperature. Deaths from cardiovascular, cerebrovascular, and respiratory diseases increase due to additional pressure being placed on the heart, brain, and lungs from excess heat. The elderly, those under the age of 1, and those with pre-existing health conditions are particularly at risk.[ii] The Lancet estimates that without human-caused climate change, we would experience around 60 days of life-threatening temperatures each year. Due to climate change, the average number of days has grown over the past two decades, and between 2018-2022, the average number of days that that people experienced health-threatening temperatures was 86. Between 1990-2000, heat-related deaths of people aged over 65 have increased by 85%, which is above the 38% increase expected if temperatures had not changed.[iii] If global mean temperatures rise to just under 2°C of warming since pre-industrial levels, and there is no substantial progress on adaptation, then annual heat-related deaths are projected to increase by 370% by midcentury.[iv]

Air pollution is another cause of poor health stemming from climate change. Climate change is increasing extreme heat and drought and therefore also the risk of wildfires. Smoke and ash can damage the heart and lungs. Furthermore, air pollution from fires reduces the ability for people to exercise outside.[v]

Transmission of infectious diseases. The changing climate, specifically higher temperatures and altered precipitation, is more suitable for the transmission of certain life-threatening infectious diseases. For example, between 1951 to 2022, the climatic suitability for the West Nile Virus, Dengue by Aedes aegypti and Dengue by Ae albopictus has increased by 4.4%, 28.6%, and 27.7% respectively.[vi]

Climate change will also impact crop growth, leading to food insecurity and the potential for malnutrition. Under a 2°C temperature increase scenario, heatwaves could lead to 524.9 million additional people experiencing moderate-to-severe food insecurity by 2041-60, which will increase the global risk of malnutrition.[vii] Moreover, undernutrition due to poor food utilisation is exacerbated by disease and a lack of good sanitation.[viii]

Finally psychological trauma will be increased due to poor physical health, loss of livestock, disruption to food supply, and displacement due to extreme weather, conflict, or violence.[ix]

All of these factors put pressure on health systems 

In a Lancet survey of cities, 27% declared that they were concerned about their health systems being overwhelmed by climate change impacts.[x]

135 countries have endorsed the COP28 UAE Declaration on Climate & Health 

The Declaration commits to eight common objectives:

1.      Strengthening the development and implementation of policies that maximise the health gains from mitigation and adaptation actions and prevent worsening health impacts from climate change, including through close partnerships with Indigenous Peoples, local communities, women and girls, children and youth, healthcare workers and practitioners, persons with disabilities and the populations most vulnerable to the health impacts of climate change, among others.

2.      Facilitating collaboration on human, animal, environment and climate health challenges, such as by implementing a One Health approach; addressing the environmental determinants of health; strengthening research on the linkages between environmental and climatic factors and antimicrobial resistance; and intensifying efforts for the early detection of zoonotic spill-overs as an effective means of pandemic prevention, preparedness and response.

3.      Recognizing that healthy populations contribute to, and are an effect of, climate resilience and an outcome of successful adaptation across a range of sectors - including food and agriculture, water and sanitation, housing, urban planning, health care, transport and energy - by prioritizing and implementing adaptation actions across sectors that deliver positive health outcomes.

4.      Improving the ability of health systems to anticipate, and implement adaptation interventions against, climate-sensitive disease and health risks, including by bolstering climate-health information services, surveillance, early warning and response systems and a climate-ready health workforce.

5.      Promoting a comprehensive response to address the impacts of climate change on health, including, for example, mental health and psychosocial wellbeing, loss of traditional medicinal knowledge, loss of livelihoods and culture, and climate-induced displacement and migration.

6.      Combating inequalities within and among countries, and pursuing policies that work towards accelerating achievement of the Sustainable Development Goals, including SDG3; reduce poverty and hunger; improve health and livelihoods; strengthen social protection systems, food security and improved nutrition, access to clean sources of energy, safe drinking water, and sanitation and hygiene for all; and work to achieve universal health coverage.

7.      Promoting steps to curb emissions and reduce waste in the health sector, such as by assessing the greenhouse gas emissions of health systems, and developing action plans, nationally determined decarbonization targets, and procurement standards for national health systems, including supply chains.

8.      Strengthening trans- and inter-disciplinary research, cross-sectoral collaboration, sharing of best practices, and monitoring of progress at the climate-health nexus, including through initiatives such as the Alliance for Transformative Action on Climate and Health (ATACH).[xi]

121 countries have signed the Declaration. You can read the full list here. Furthermore, US$1 billion of funding has been pledged for mitigation and adaption programmes, particularly those that transform health systems, address the environmental determinants of health, and ensure that communities and vulnerable population populations are protected.[xii]


[i] WHO- COP28 Health Day

[ii] LSE & Grantham Institute- How does climate change impact health?

[iii] The Lancet- Key findings of the 2023 report of the Lancet Countdown on health and climate change

[iv] The Lancet- The 2023 report of the Lancet Countdown on health and climate change: the imperative for a health-centred response in a world facing irreversible harms

[v] LSE & Grantham Institute- How does climate change impact health?

[vi] The Lancet- Key findings of the 2023 report of the Lancet Countdown on health and climate change

[vii] The Lancet- The 2023 report of the Lancet Countdown on health and climate change: the imperative for a health-centred response in a world facing irreversible harms

[viii] LSE & Grantham Institute- How does climate change impact health?

[ix] Ibid

[x] The Lancet- Key findings of the 2023 report of the Lancet Countdown on health and climate change

[xi] COP28 UAE- COP28 UAE Declaration on Climate and Health

[xii] The Lancet- Health Day at COP28: a hard-won (partial) gain

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Gemma Drake
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Gemma recently graduated with a degree in International Development. She is currently studying for an MSc in Sustainable Urbanism, which examines urban planning and urban design through a sustainability lens. “I’m passionate about addressing sustainability challenges in a holistic and pragmatic way. Zero Carbon Academy's diverse range of services targets many of the areas that need support if we are to transition to a liveable future. I’m excited to see the impact that the Academy makes.”

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