The Global Health Impacts of the Climate Crisis

The climate crisis poses severe risks to human health, which have been clearly and extensively documented by scientists and researchers.Reference Rocque, Beaudoin and Ndjaboue¹ Fossil fuel combustion propels global warming and exacerbates air pollution, while altering weather patterns leading to a more unstable and unpredictable climate. These changes increase the frequency of more intense and destructive storms, longer and more severe heat waves, larger wildfires accompanied by harmful air quality, and persistent droughts. A warming climate can expand the range of infectious diseases, allowing tropical and vector-borne diseases to spread into more areas. Climate change is undermining food and water security, as poverty and systemic vulnerability increase.Reference Romanello, Di Napoli and Drummond² A more volatile climate will increase dislocation, violence, and mental health consequences, with significant increase in migration.Reference McMichael³ Children are particularly vulnerable to the harmful health effects of climate change.Reference Perera and Nadeau⁴

Addressing the health impacts of the climate crisis presents difficult challenges, which demand both efforts to mitigate climate change through reductions in greenhouse gas emissions and other initiatives to reduce carbon in the atmosphere and efforts to adapt to climate change through policies to reduce the public health impacts of climate change through resilient health systems and programs to limit negative climate-related impacts on social determinants of health.⁵ Such mitigation and adaptation efforts have required global action under international law.

The Climate Crisis and International Law

Effort to address climate change through international law have centered on the 1992 UNFCCC and its two major protocols — the 1998 Kyoto Convention and the 2015 Paris Agreement. These legal instruments outline a series of international commitments that obligate national governments to reduce carbon emissions, setting an overall target to limit global temperature increases.⁶ The UNFCCC also established annual Conferences of Parties (COP) to allow governments and other participants to continue to develop climate strategies over time.

This global climate governance regime, however, has rarely focused on health. Human health was only mentioned in passing as a possible adverse effect of climate change in the UNFCCC. The Paris Agreement contains a more substantial, but still conceptually-limited reference to health, with the drafters acknowledging that parties should respect, promote, and consider the right to health along with other core human rights obligations. Moreover, with rare, recent exceptions, health has not featured prominently in the discussions at COP meetings or in related policymaking initiatives.

Global Health Law and Policy and the Climate Crisis

Yet, global health organizations and institutions have increasingly recognized the dire health implications of the climate crisis and have repeatedly asserted the importance of including health in climate change mitigation and adaptation efforts. Over the past decade, the World Health Organization (WHO) has emphasized the global health implications of the climate crisis, designating climate change as “the single biggest health threat facing humanity,”⁷ publishing numerous reports and analyses on climate change adaptation,⁸ and building up its capacity to advocate for global health within formal and informal global climate policymaking.

Other United Nations (UN) institutions have also begun to pay greater attention to the intersection of health and the climate. Human rights instruments and related guidance have long examined the impact of climate change on a wide range of environmental health-related human rights.Reference Hesselman, Meier, Gostin and Meier⁹ Nevertheless, policy efforts to mainstream human rights in climate policy — with rights-based approaches linking health and climate change — have only occurred only in the last few years, with the UN Human Rights Council and the UN General Assembly recently recognizing the right to a clean, healthy, and sustainable environment as a human right¹⁰ and the UN Special Rapporteur adopting a seminal report on the human rights impacts of climate change.¹¹

Global health scholars and activists have similarly raised the alarm that health considerations should be more prominent in the discourse and obligations around the climate crisis. Recognizing the urgency of this issue, over 200 journals simultaneously published a joint editorial demanding action to limit fossil fuel emissions, acknowledging that “[t]he greatest threat to global public health is the continued failure of world leaders to keep the global temperature rise below 1.5° C and to restore nature.”Reference Atwoli, Baqui and Benfield¹² In furthering global health scholarship to support the climate change response, the development of the One Health and Planetary Health fields have helped to recharacterize the relationship of natural environments and human health in ways that clearly demonstrate their interconnection.Reference Phelan, Gostin and Meier¹³

Seizing the Opportunity to Link Global Health Law and Climate Change

The upcoming COP28 meeting in November-December 2023 has designated, for the first time, a full day of meetings that will focus on health. This prominent recognition of the centrality of health to climate mitigation and adaption efforts provides a crucial opportunity for the global health community to speak directly with COP participants and chart a more cohesive path to consider global health and climate change together.

In recognizing these interconnections between global health and climate change, participants in the COP28 health discussions should consider the many advantages of viewing the impact of climate change through the lens of public health. Health considerations have universal and personal appeal that may help transcend the political opposition and lack of urgency displayed by opponents of stronger mitigation measures.Reference Phelan, Van Daalen, Gostin and Meier¹⁴ Moreover, given the outsized impact that the climate crisis will have on health, protecting health should become a priority issue in climate change adaptation planning.

WHO has a particularly vital role to play. COP28 provides a prominent platform for WHO to utilize its work examining the linkages between health and climate change to guide conversations about global health impacts that go beyond discussions of health systems — to consider health outcomes, health equity, social justice, and social determinants of health. While trust in health experts may be less robust due to reactions to the COVID-19 pandemic, climate warnings from health experts may be more conducive to spur policy and behavioral changes than appeals from less-trusted messengers.

WHO should likewise continue to expand its infrastructure to pursue new policies and programs that build on COP commitments. After the COP26 meeting in 2021, WHO formed the Alliance for Transformative Action on Climate and Health, which has received commitments from over 60 countries to pursue climate-resilient and sustainable low-carbon health systems.¹⁵ WHO should be poised to implement additional new initiatives for climate mitigation and adaptation efforts linked with global health — arising out of COP28 and future international climate meetings.

Just as it is imperative to center health considerations in all high-level discussions about climate change mitigation and adaptation, it is similarly essential for the global health community to build climate considerations into global health initiatives. The COVID-19 pandemic revealed starkly the limitations of global health governance. Nevertheless, the pandemic response can provide important lessons for creating more robust and interconnected capacity to combat future global health crises.Reference Gable¹⁶ The global health community should consider the future implications of the climate crisis on global health as it debates how to strengthen global legal authorities through the revised International Health Regulations and the Pandemic Treaty.Reference Meier, Habibi and Gostin¹⁷

Finally, global health policymakers must recognize the importance of equity and human rights in climate change policy, given the interconnected effects that policy decisions have on health and the social determinants of health. Equity has critical importance at the intersection of global health and climate change, as the most affected populations will be those least responsible for the emissions driving the effects of climate change.¹⁸ Leaders, policymakers, and advocates in climate justice and global health have an opportunity to come together and build on the compatible frameworks already being constructed to combat inequity and injustice across multiple dimensions of global policy, including efforts related to One Health,Reference Carlson and Phelan¹⁹ Planetary Health,²⁰ Health in All Policies,²¹ and the Sustainable Development Goals.Reference Marmot and Bell²² Human rights frameworks can inform these discussions and undergird initiatives to advance global health equity in climate change policy under an established and evolving global legal framework.Reference Meier, Bustreo and Gostin²³