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Durham Law School

The World Health Organization identifies climate change as the biggest health threat facing humanity.

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Biggest health threat facing humanity

The World Health Organization identifies climate change as the biggest health threat facing humanity. 

In view of this, one might expect health to feature heavily in the international legal framework regarding climate change, mainly composed of the 1992 Framework Convention on Climate Change (UNFCCC) and the 2015 Paris Agreement. 

The word “health” is indeed mentioned in two places in the UNFCCC. The first mention occurs where “adverse effects of climate change” are explained as “changes in the physical environment or biota resulting from climate change, which have significant deleterious effects on the composition, resilience or productivity of natural and managed ecosystems or on the operation of socioeconomic systems or on human health and welfare.” The second mention refers to the obligations of Parties to take “climate change considerations into account, to the extent feasible, in their relevant social, economic and environmental policies and actions, and employ appropriate methods, for example impact assessments, formulated and determined nationally, with a view to minimizing adverse effects on the economy, on public health and on the quality of the environment, of projects or measures undertaken by them to mitigate or adapt to climate change.” 

In the Paris Agreement, “health” is only mentioned in the preamble. Therein, it is acknowledged that “climate change is a common concern of humankind” and that “Parties should, when taking action to address climate change, respect, promote and consider their respective obligations on human rights, the right to health, the rights of indigenous peoples, local communities, migrants, children, persons with disabilities and people in vulnerable situations and the right to development, as well as gender equality, empowerment of women and intergenerational equity.” 


Focus on Parties’ obligations 

While these two international agreements are not fully agnostic to the effects of climate change on human health (see the UNFCCC first mention), they nevertheless seem to place a stronger focus on Parties’ obligations to consider the effects of their actions on climate change for public health or the right to health. This does not mean that the “regime” (the global framework that governs the international response to climate change) is not capable of considering the concrete short and long term effects of climate change on human health, but how could it incorporate more explicitly the mounting scientific evidence on the health-climate nexus? International law on climate change is continually evolving, and two key avenues exist for including a more distinct approach to human health. The following explores how this could be achieved. 


Decisions on an international level 

Firstly, at the international level, Parties of the UNFCCC and the Paris Agreement adopt further decisions at the yearly UN climate conferences (Conferences of Parties (COPs) and meetings of Parties under the Paris Agreement (CMAs)). These decisions often include guidance for the implementation of the provisions of the agreement, and they relate to key agenda items and work programmes that Parties consider at these conferences. Health is a key theme of the UN Nairobi work programme, for example. A synthesis report was published in 2017 on “Human health and adaptation: understanding climate impacts on health and opportunities for action.” These work programmes feed into the decisions adopted by Parties, and this is where the developmental potential of the regime towards health awareness lies. Parties’ decisions often include more detail than the main treaty text, and they can interpret, develop, and even expand the meaning of treaty provisions.  

For example, the Sharm-El Sheikh Implementation plan, adopted at COP27 in 2022 as the cover decision (there are more decisions adopted for the various agenda items), repeats the Paris Agreement’s wording on health but further states that “Parties should, when taking action to address climate change, respect, promote and consider their respective obligations on human rights, the right to a clean, healthy and sustainable environment, the right to health (emphasis added).” Even though these further decisions may not immediately create new legal obligations, the wording reflects a common understanding of Parties at the international level, that their human rights obligations, including the right to health and the right to a healthy environment, must play a distinct role in addressing climate change. Subsequent COP decisions can build on previous decisions and thereby consolidate a certain interpretation of the treaty regime. This could include detail on what it means to promote the right to health in taking action to address climate change. It could also usher in a stronger focus on the impacts of climate change on human health, based on health attribution studies. The interpretation of the treaty through Parties’ decisions refines the content of the respective provisions and ultimately influences how the international law should be applied at the national level. The input of experts into the work programmes is therefore crucial, and there are various opportunities to make submissions to the UNFCCC on agenda items that could include health, such as on adaptation priorities. Health experts can make written submissions, work with governmental and non-governmental institutions, to ensure that health is more fully included in the regime. 

Linking health impacts to climate change and assessing the human contribution to changes in observed impacts, can provide important evidence and inform the decision-making of COPs. The upcoming COP28 in Dubai is of particular importance, as the first global stocktake that evaluates the collective progress towards achieving the purpose of the Paris Agreement and its long term goals will draw to a close, with the political consideration of outcomes. The technical assessment phase of the global stocktake has already concluded. The summary report was published on 8 September 2023 and highlights the health benefits of carefully designed climate action, in terms of reduced air pollution and dietary changes. However, the report does not explicitly mention the impact of climate change on human health, and this is certainly a gap where more work needs to be done, driven by interdisciplinary efforts that involve medical professionals, social scientists, lawyers, and policy makers. 


Fulfilling obligations on a domestic level 

The second avenue to influence government action stems from the way in which Parties fulfil their legal obligations under the treaty. Parties define and interpret the scope of the agreement not only through COP decisions but also through their domestic action. For example, over 70% of Parties already include “health” in their adaptation priorities, as part of their nationally determined contributions (NDCs). These NDCs are the pledges they make to the UNFCCC for their climate action every five years, as mandated by the Paris Agreement. NDCs also constitute the yardstick for national laws, policies, and ultimately, national and local climate action. The Global Climate and Health Alliance is calling on governments to design “Healthy National NDCs.” Through including a stronger focus on health in NDCs, and dedicating more specific attention to projected emissions trajectories and corresponding future extreme events and slow onset events, and their impacts on human health, Parties can not only set national targets and send a political signal at the domestic level. They also “set the tone” at the international level: their practice in designing NDCs contributes to legally relevant State practice. NDCs are registered by the UNFCCC Secretariat and are publicly available; they constitute an important and accessible source of information. One Party’s practice can influence the practice of other Parties and thereby elevate the internationally expected standard for health consideration in NDCs. 

This second approach thus works “bottom up” from the national to the international level. Ultimately, a better understanding of the health impacts of climate change, in combination with knowledge on the health benefits of climate action, will strengthen the case for ambitious national emissions reduction targets and long-term low greenhouse gas emission development strategies that result in sustainable development. NDCs could and should become a source for climate law and for health law—certainly for Parties that aspire to be global climate leaders. 

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This article is republished from BMJ. It was written by Petra Minnerop, professor of international law, Durham Law School, and director of Centre for Sustainable Development Law and Policy. Read the original article.