This paper argues that the climate and nature crises are interconnected and should be treated as a single global health emergency. The current approach of addressing these issues separately is deemed a dangerous mistake. The authors highlight the interconnectedness of climate change and biodiversity loss, emphasizing that damage to one system creates cascading effects on the other. For instance, extreme weather events destroy plant life, leading to soil erosion and reduced carbon storage, thereby exacerbating global warming. Climate change is also rapidly becoming the primary driver of nature loss, surpassing deforestation and other land-use changes. The paper stresses the importance of recognizing nature's restorative power and the crucial role of indigenous land and sea management practices in regeneration. While restoring one subsystem can benefit another (e.g., soil replenishment removing greenhouse gases), actions beneficial for one may harm the other (e.g., monoculture forestry reducing biodiversity). The authors set the stage for discussing the indivisible planetary crisis's significant impacts on human health and the urgent need for a unified response.

The paper draws upon a range of existing literature to support its arguments. It cites previous editorials from health journals highlighting the health impacts of both climate change and biodiversity loss. References include reports from the World Health Organization (WHO), the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), and various scientific publications demonstrating the links between environmental degradation and human health. Specific examples of the literature cited include studies on the impacts of climate change on infectious disease spread, the effects of biodiversity loss on food security and nutrition, and the mental health benefits of nature exposure. The authors also reference reports from the UN and other international bodies regarding commitments made at COPs (Conferences of the Parties) on climate change and biodiversity, highlighting the gap between promises and actions.

The methodology of this paper is primarily a review and synthesis of existing literature and expert opinion. The authors, representing a wide range of medical journals, have collaboratively written this commentary to emphasize the urgency of the situation. Their approach involves consolidating evidence from various scientific disciplines to paint a comprehensive picture of the interconnected nature of the climate and biodiversity crises and their impact on global health. The paper does not present original research data but rather synthesizes and interprets existing research to make a persuasive case for a unified approach to tackling this global challenge. The strength of their argument lies in the collective voice of over 200 health journals supporting the declaration of this crisis as a global health emergency.

The paper's key findings center on the interconnected nature of climate change and biodiversity loss, and their devastating consequences for human health. The authors argue that: 1) Climate change and biodiversity loss are intrinsically linked, creating a self-reinforcing cycle of environmental degradation. 2) This combined crisis poses a significant threat to human health through various pathways, including increased infectious diseases, food insecurity, water scarcity, and mental health issues. 3) The impacts of this crisis are disproportionately felt by vulnerable populations. 4) Current efforts to address these issues separately are inadequate. 5) The World Health Organization (WHO) should declare the combined crisis a global health emergency. 6) Harmonizing the COP processes for climate change and biodiversity is essential for effective action. 7) Health professionals should advocate strongly for both biodiversity restoration and climate action. 8) Political leaders must acknowledge the health threats and benefits related to addressing the crisis. The paper provides numerous examples to support these findings, including data on the loss of genetic diversity in food systems, the decline in wildlife populations, the increasing spread of infectious diseases due to habitat change, and the impacts of air and water pollution.

The paper's findings strongly support the urgent need for a unified global response to the climate and biodiversity crises. The authors argue that by treating these challenges as separate issues, we are failing to address the root causes of the problem and missing opportunities for synergistic solutions. The declaration of this combined crisis as a global health emergency would provide a framework for coordinated international action, potentially mobilizing resources and expertise to address the problem effectively. The discussion section also highlights the need for integrated national plans that address both climate change and biodiversity loss, advocating for a shift in values related to human-nature relationships and a reduction in inequalities. The authors emphasize the importance of recognizing the multiple benefits to health from tackling these issues, creating a compelling case for prioritizing coordinated and comprehensive action.

The paper concludes that the climate and nature crises represent a single, indivisible global health emergency that demands immediate and unified action. It calls upon the WHO to officially declare this emergency, urging harmonization of the COP processes and stronger advocacy from health professionals and political leaders. Future research should focus on developing and evaluating integrated strategies that simultaneously address climate change and biodiversity loss, ensuring their effectiveness and equitable implementation across different regions and communities.

The main limitation of this paper is its reliance on a synthesis of existing literature rather than presenting original research. However, the strength of its argument lies in its comprehensive review of the extensive body of evidence supporting the interconnectedness of climate change, biodiversity loss, and their profound impacts on global health. The paper's recommendations are based on this comprehensive review and represent a call for policy action rather than a detailed analysis of specific interventions.