# Session Overview Learning outcomes By the end of this session, you should be able to: · Explain the main causes of climate change and some of the health impacts, both already observed and expected in the future · Identify specific opportunities across sectors for climate change mitigation that will also produce improvements in population health · Appreciate the types of adaptation and climate resilience policies that address the risks associated with climate change and how they can benefit health even in the near-term · Give examples of inequity and injustices relating to climate change and health impact # 1. Climate change to climate emergencies On 10th April 2024 [[Simon Stiell]], the Executive Secretary of the United Nations Framework Convention on Climate Change ([[UNFCCC]]) declared that we have ‘two years to save the world’. The UNFCCC predicts that, if insufficient action is taken within this timeframe, then not only will the 2015 Paris Agreement’s target of limiting global temperature rises to 1.5°C above pre-industrial levels not be met, but will likely be surpassed (Masson-Delmotte et al. 2019) The COP29 Special Report on Climate Change and Health states, this means putting health at the heart of climate policy, not only because failure to arrest climate change will have accelerating negative consequences for health and implications for equity, but also because health represents a powerful advocacy tool to influence funders and policy (WHO 2024). ## 1.1 Climate and weather ## 1.2 Changes within and of the Earth's climate system The United Nations Framework Convention Climate Change ([[UNFCCC]]) refers to non-human causes’ variations in the Earth’s climate as ‘climate variability’ or ‘natural variability’ and human caused changes as ‘climate change’ (Berger et al. 2023) or ‘anthropogenic climate change’. Here, climate change is defined as a persistent and statistically identifiable change in the mean and/or variability of the climate in a particular region or at a global scale. Climate scientists, which include geologists, palaeoclimatologists, meteorologists, physicists, geochemists and increasingly archaeologists, historians, anthropologists etc. (Carey 2012; Zalasiewicz and Williams 2009; Chakrabarty 2009), have demonstrated that since the Earth’s formation (approx. 4.5 billion years ago), its climate has varied significantly over geological time (see figure 2). ## 1.3 [[Anthropocene|Anthropogenic]] climate change Anthropogenic climate change is most directly the consequence of the accumulation of greenhouse gases (GHG) in the earth’s lower atmosphere. Beginning in the late 19th century combustion of coal and later, oil, natural gases and cement production (figure 4), have come to be the primary drivers of anthropogenic climate change (IPCC 2021, 62–69). In addition to changes in temperatures, the report expresses high confidence that anthropogenic climate change is also contributing to (IPCC 2021): - increases in glacial melt and decreases in snow and ice cover; - rises in global sea level (i.e. of approximately 0.2m between 1901 to 2018); - shifts in ecosystems on land, such as climates zones shifting poleward in both southern and northern hemispheres, observed lengthening of growing seasons in northern parts of the north hemisphere and increases in ocean acidification and decreases in oxygen levels in the oceans. ## 1.4 The evolution of global climate change policy the first World Climate Conference wasn’t held till the end of the 1970s (Gupta 2010). This was the first global level meeting to acknowledge humans’ increasing impacts on local and regional climates and the potential existential threats they pose to human life (WMO 1979) One of the outcomes of the international meetings, was the 1987 [[Montreal Protocol on Substances That Deplete the Ozone Layer]], which was the first universally ratified UN treaty, and is recognised as one of the most successful international environmental agreements to date (Gupta 2010). Another international meeting led to the UNEP and World Meteorological Organisation (WMO) founding of the IPCC, and the production of its first report in 1990 (Gupta 2010; Bodansky 2001). This was accompanied by a UN resolution to set up the Intergovernmental Negotiating Committee on the Climate: the United Nations Framework Convention on Climate Change (UNFCCC) and the conference of parties or COP (the supreme governing body of the convention) (UN 1990), which came into force in 1994 (see figure 7). [[Environmental justice]] The first international treaty to propose reductions in emissions of climate active pollutants – initially greenhouse gases (GHG) was the Kyoto Protocol, which was set at COP3 in 1997 and came into force in 2005. However, the US never ratified the [[Kyoto Protocol]] (see figure 7), while Russia, Japan and Canada either did not ratify it or take up any or substantial targets (Maslin, Lang, and Harvey 2023). One of the reasons given by the US for not participating in the Kyoto Protocol, was according to President Bush at the time, ‘’[…] it exempts 80 percent of the world, including major population centers such as China and India, from compliance, and would cause serious harm to the U.S. economy’ (Editor 2001) This reflected ongoing tensions that extended back at least as far as the cold war, as well as with early international environmental and anti-colonial movements in the 20th century (Riley Case 2023). Put otherwise, it reflects ongoing debates over historical injustices (e.g. colonialism and differential access to and combustion of fossil fuels by so called developed countries), responsibilities for addressing contemporary inequities (e.g. poverty, differences in socioeconomic development, access to renewables) and future harms attributable to climate change. The initial UNFCCC attempted to address such injustices and inequities partly through the notion of ‘common but differentiated responsibilities’, when it stated that (UN 1990): > However, what this means in practice continues to be a point of conflict for climate change agreements and implementation of effective international policy. Since the initiation of the IPCC and UNFCCC, ==these tensions resulted in nations being divided into developing and developed and it was initially determined that the burden of responsibilities for the first climate change targets was reserved only for developed countries.== However, not only have the definitions of developed and developing countries not been clearly articulated, but associated responsibilities and policy consequences of these divisions are continually questioned. This was ever more evident at the 2009 COP15 in Copenhagen (see figure 7), when a proposal was made to shift from targets focused on GHG reductions and instead on targets limiting temperature increases to 1.5°C to 2°C. Disagreements emerged amongst developing countries, who saw large GHG emitters - India and China’s - refusal to propose more ambitious GHG cuts as barriers to limiting both global temperature increases to 1.5°C, and to addressing climate risks that would affect more vulnerable countries, such as the Small Island Developing States (SIDS), like the Maldives or Micronesia. At the same time, the US, under President Obama, not only were later found to be eavesdropping on other delegates, but arrived late and convened their own meeting with Brazil, South Africa, India and China, excluding all other UN nations. Together they created the [[Copenhagen Accords]], ==which set the temperature target as 2°C, avoided any mention of 1.5°C, was non-binding and did not provide any commitments to emission reductions (Maslin, Lang, and Harvey 2023). However, it formed part of processes that would consolidate in the later seminal 2015 COP21 Paris Agreement.== ## Activity 1: Contributors to anthropogenic climate change and climate policies # 2. Climate change and health ## 2.1 Direct health effects ## 2.2 Ecosystem mediated health effects Deforestation. Drought. Floods. Changes in temperature and ecosystems (e.g. deforestation) have been shown to contribute to shifts and increases in climate-sensitive diseases, including water (e.g. cholera and schistosomiasis), food (e.g. Salmonella) and vector (e.g. malaria and dengue) -borne diseases (Watts et al. 2018; Cissé 2019; Duchenne-Moutien and Neetoo 2021; Semenza, Rocklöv, and Ebi 2022). Extreme weather events and climate change also contribute to mental health issues (WHO, 2022), including eco-anxiety. ## 2.3 Indirect, deferred and displaced health effects Extreme weather events contributed to increasing loss of livestocks and crops, as well as destruction of homes and infrastructure, including health facilities. Loss of livelihoods, reduce access to foods, shelter, water and health care access, so it exacerbates already existing issues of poverty and ill health. Similarly, increases in climate change-related temperatures contributing to processes such as desertification, sea level rises, ocean acidification and other climate and ecosystems changes may lead to worsening poverty and health, (Agache et al. 2022; Cissé et al. 2022); e.g. through loss of agriculturally productive land. Temperature related shifts may lead to more chronic and irreversible consequences. For example, the melting of glaciers and ice in polar regions is leading to sea level rises and shrinking coastlines, which will continue to contribute to the loss of homes, as well as loss of agricultural and urban land (Mastrorillo et al. 2024). In addition, increases in extreme weather events (e.g. heatwaves, flooding) due to climate change may result in the need for temporary or permanent displacement of people within a country. It is very important to recognise that any indirect health effects stemming from loss of livelihoods, mass displacement, migration and conflict attributed to climate change are not ‘natural’. Rather they are inseparable from how humans’ activities are driving climate change and how global and national policies and decisions that shape responses to climate change’s consequences (e.g ## Activity 2: Eco-anxiety: the sufficiencies and insufficiencies of climate action What are your feelings with relation to climate change? Do you think sufficient action is being taken? What in your view are the biggest barriers to sufficient and effective climate measures? Do you think action such as employed by Just Stop oil (website and videos), Extinction rebellion (UK and global website and video) and other activist groups are justified? Do you or anyone you know suffer from eco-anxiety? Post some of your own personal reflections and feelings on climate change and the sufficiency of current and proposed measures to address climate change in the respective Moodle form and respond to at least one of your fellow student’s posts. Feedback and thoughts: You may share similar feelings with your fellow students or differ. Try to explore and discuss this with each other; why you think this might or might not be the case. Does where you live, your education, location, education etc shape it? If so, how? Share your thoughts with your fellow students. # 3. Mitigating climate change Although the overarching goal of mitigation is to prevent climate change derived risks and negative societal, economic and health impacts, this section is concerned specifically with demonstrating that many climate change mitigation policies can simultaneously improve human health. This is sometimes referred to as a ‘co-benefits’ approach, whereby climate mitigation policies also confer benefit for humans’ health and vice versa (WHO 2012; 2011). Health professionals have repeatedly emphasised that co-benefits to health may be large, providing a powerful added impetus for implementation of climate mitigation policies (Mogwitz et al. 2022; Maibach et al. 2021; Members 2022; Machalaba et al. 2015). This was explicitly the case in COP28, where ministers of health and environment joined together to start to formally embed the co-benefits approach to health and climate change into climate policy commitments, such as the NDCs (COP28 UAE 2023). The health sector is estimated to contribute 5.2% of global GHG emissions, with emissions varying considerably between countries; the country with the highest per capita health sector emissions (i.e. the United States) being 50 times that of one the lowest - India (Romanello et al. 2022). Health co-benefits from climate change mitigation can also accrue for reasons directly related to mitigation action, but which are independent of reductions in air pollution (Scovronick et al. 2015). For example, shifts to active transport such as increased walking and cycling which improvs fitness and therefore health (Giles-Corti et al. 2010; Wolkinger et al. 2018), or changes in diets (to healthier diets) and therefore a reduction in diet-sensitive diseases. ## Activity 3: multiple health co-benefits of climate change mitigation measures Some climate change mitigation actions, and particularly those that promote technological solutions, may primarily focus on improving health through reductions in air pollution. While the positive impact on health of these actions may be large, other mitigation actions also produce powerful health benefits through additional pathways. Choose one of the following mitigation actions or propose your own, describe the potential benefits to health and outline the potential challenges to introducing them in your country: 1) Prioritizing active travel (walking/cycling) instead of private car use 2) Promoting increased consumption and production of healthy plant-based diets and/or locally produced foods ### Feedback Prioritizing active travel reduces air pollution from mechanized vehicles as well as increasing physical activity. This is associated with a range of health benefits including the prevention of cardiovascular disease, diabetes, cancer and depression (Warburton, Nicol, and Bredin 2006). It also reduces noise pollution, and assuming the provision of safe infrastructure, can diminish the sizeable health burdens from road traffic injuries (Lim et al. 2012). As discussed in the session, consuming diets that are high in plant-based foods and low in red meat, has great potential health (and climate) benefits – addressing both a key source of methane emissions (from agriculture – particularly cattle rearing) as well as the growing worldwide disease burdens from diet-sensitive non-communicable diseases (diets high in red meat lead to a higher risk of cardiovascular disease). # 4. Health adaptation and climate resilience Even if action is taken to halt GHG emissions, the continued presence of long-lived GHG (such as CO2 and N2O) in the atmosphere and ongoing effects of other Climate Active Pollutants. The more we delay mitigation, the harder societal, economic, and health consequences of climate change will be. Hence, it is important that mitigation actions are complemented with adaptation actions designed to help population avoid or minimize the health consequences of climate change. Without explicit attention to questions of adaptation and resilience, countries and their health systems risk not only experiencing severe climate-related setbacks (e.g. lack of sufficiently trained staff and equipment), but perhaps even health system collapse (WHO 2023). WHO did not stay silent. They help countries to develop health adaptation and climate resilient health system policies, alongside the IPCC's broader proposal for national adaptation plans and what it refers to as climate resilient development. Here, resilience and adaptation are complementary concepts with overlapping meanings. WHO defines resilient as ability to anticipate, respond to, cope with, recover from, and adapt to climate-related shocks and stress, to bring about sustained improvements in population health, despite an unstable climate (WHO 2023, pg. 7) Whereas, adaptation in the context of health is the process. Process of adjustment to actual or expected climate and its effects which seeks to moderate harm or exploit beneficial opportunities. ==These policies focus on measures to reduce vulnerabilities, protect against climate-related exposures and ensure health system have the capacities to adequately and appropriately respond to climate-sensitive health risks.== The policies are basic public and health system interventions, as well as broader policies aimed at sustainable, resilient development and poverty alleviation. They include vaccination programs, improved water, sanitation and food security, provision of satisfactory housing, early warning systems and relevant action plans (e.g. for heat and preparation for other extreme weather events), properly trained health staff and sufficiently supplied health facilities etc (Cissé et al. 2022); ## Integrating activity Climate change is predicted to contribute to mass displacement and need for population migration within and between countries. For one population, region or country vulnerable to climate related impacts (such as sea level rises or desertification) and thus potential population displacement: - provide some relevant background description of your chosen population, region or country, including location, and briefly explain why they are at risk of displacement due climate change - propose two possible adaptation policy actions, discuss any potential interactions between them, their health benefits and any barriers/limitations to their implementation and success, including questions of inequities. Some potential resources include: - IPCC data atlas - Our world in data - International Energy Agency - The Lancet Countdown on Health and Climate Change - Intergovernmental Panel on Climate Change - International Monetary Fund - Climate change policy database - Climate Change tracker - OECD Climate Change action dashboard - Climate Change performance index - Climate Change knowledge portal for development practitioners and policy makers - World Bank group - Climate Watch Data - Carbon Brief - Migration data portal - Migration policy - Institute of Migration, environmental migration # 5. Summary In 2025, after 29 COPs, anthropogenic climate change remains a major threat to human health and the flourishing of the planet. Multiple international climate agreements, national policies, greater awareness and increasing mitigation and adaptation measures have made little tangible impact on reducing CAPs and the world is on track for a global temperature increase of over 2.5°C above pre-industrial levels by 2030. In addition to the direct impacts from heat and, and more intense and/or frequent extreme weather events, other climate-related risks will likely include increases or changed distributions of certain vector-borne diseases, increased undernutrition, forced migration, increased conflict and exacerbation of other environmental issues. Whilst its increasingly unlikely that future climate change can be fully mitigated, the scale and intensity of negative human health and other consequences can still be reduced considerably through mitigation actions, which in themselves help improve population health. For example, reducing emissions of CAPs leads to cleaner air, whilst more indirect effects on health include those from shifting to healthier low-GHG diets or benefitting from the physical activity associated with active travel in place of motorised. Even with substantial mitigation measures, climate change will continue to occur for some time and therefore substantial adaptation is also urgently needed to limit and protect against negative health impacts. This must be done in ways that address inequities both in populations’ and countries’ exposure to climate risks and their respective abilities to adapt (e.g. access to sufficient resources, funds etc). Adaptation policies, in many countries, already include those that have an immediate benefit for health, such as disaster preparedness and relocation of population away from flood plains, coasts and small islands, but further adaptation efforts are needed, such as developing resilient healt # 6. References ## 6.1 [[Essential readings]] Agache, Ioana, Vanitha Sampath, Juan Aguilera, Cezmi A. Akdis, Mubeccel Akdis, Michele Barry, Aude Bouagnon, et al. 2022. ‘Climate Change and Global Health: A Call to More Research and More Action’. Allergy 77 (5): 1389–1407. https://doi.org/10.1111/all.15229. Rossa-Roccor, Verena, Amanda Giang, and Paul Kershaw. 2021. ‘Framing Climate Change as a Human Health Issue: Enough to Tip the Scale in Climate Policy?’ The Lancet Planetary Health 5 (8): e553–59. https://doi.org/10.1016/S2542-5196(21)00113-3. ## 6.2 [[Recommended reading]] WHO. 2024. ‘COP29 Special Report on Climate Change and Health: Health Is the Argument for Climate Action.’ Geneva: World Health Organisation. https://cdn.who.int/media/docs/default-source/environment-climate-change-and-health/58595-who-cop29-special-report_layout_9web.pdf. Kashwan, Prakash, and Jesse Ribot. 2021. ‘Violent Silence: The Erasure of History and Justice in Global Climate Policy’. Current History 120 (829): 326–31. Rouf, Khadj, and Tony Wainwright. 2020. ‘Linking Health Justice, Social Justice, and Climate Justice’. The Lancet Planetary Health 4 (4): e131–32. https://doi.org/10.1016/S2542-5196(20)30083-8. Ingle, Harriet E., and Michael Mikulewicz. 2020. ‘Mental Health and Climate Change: Tackling Invisible Injustice’. The Lancet Planetary Health 4 (4): e128–30. https://doi.org/10.1016/S2542-5196(20)30081-4.