This year in the U.S., wildfires killed 97 people in Maui. Last year, floods submerged hundreds of villages in Pakistan, displacing at least 130,000 people and spreading diseases. The unrelenting drought that has devastated the Horn of Africa has left more than 20 million people facing acute food insecurity. Already, 7 million people die each year from air pollution, more than the global death toll during the entire COVID-19 pandemic.

Today, the world is on track for a temperature rise of between 2.4C and 2.6C by the end of this century, with the most resource-vulnerable populations–who contribute the least to carbon emissions–bearing the brunt of the devastating effects. The climate and health crises are trapping people in a cycle of poverty and despair. Estimates project that 1.2 billion people will be displaced by climate change by 2050. Action is needed today–because we are not ready for tomorrow.

Long under-invested, national health systems are ill-equipped for today’s challenges. Some 90% of countries reported disruptions to health services during the COVID-19 pandemic. Less-resourced countries suffered the most–and we saw health outcomes, including in malaria and maternal mortality, backslide.

Mitigation and reduction of greenhouse gas emissions are paramount to reducing the impacts of climate change and the healthcare sector, which is responsible for 4-5% of total greenhouse gas emissions, can play a significant part in that effort. Up to 95% of the sector’s overall emissions can be reduced–from the supply chain to the patient care delivery pathway. The reinvention of the patient care pathway could also improve health outcomes, in addition to reducing emissions in a number of ways that range from decarbonizing health facilities to providing care remotely or closer to home.

However, mitigation alone is not enough. To address the harm happening today, we must urgently deal with the current and future impacts of climate change on our health by building stronger, more resilient health systems, supported by a fit-for-purpose health workforce able to deal with the burden of disease we face.

It begins by shifting the narrative and making clear that healthcare is an investment, not a cost. Studies have shown the economic return on every dollar invested in health is at least $2-$4. Climate and health investments are win-win. For example, investments in reducing air pollution will save lives but also prevent a future loss of the almost $50 trillion that has been spent since 2010 to address its consequences. Prioritizing health not only leads to better health outcomes, it also grows economies, creates jobs, and promotes social inclusion.

A critical barrier to tackling the climate and health crisis is the size and focus of financing. Adaptation needs in low and middle-income countries could skyrocket to as much as $340 billion a year by 2030. Yet adaptation funding today stands at less than one-tenth of that amount, with less than 5% of available funding targeting health specifically. The funding simply isn’t there today. A hybrid financing approach will be required as official development assistance will not be able to meet the financing needs alone.

We must ensure that most of the financing focuses on accelerating local adaptation efforts. Our best chance of tackling the devastating impacts of climate change is through investing in local communities who know what they need and ensuring strong, resilient health systems, supported by a well-resourced health workforce who can respond to the challenges of climate change. Communities must be at the center of decision-making and prioritization. They can help scale effective interventions rapidly and sustainably. For example, in Bangladesh, local groups have established a community-based early warning system to advise residents of impending floods.

Our only choice is bold action for our health and well-being. And it should start now. This year marks a pivotal moment. For the first time, there will be a dedicated Health Day at COP28, underscoring the growing understanding of this critical threat. While we aspire to generate a consensus on the global health response to climate change and focus on health adaptation, our discussions must urgently translate into action that shifts the narrative.

We must include health outcomes in the metrics against which we measure climate progress. We need greater and more potent financing mechanisms created to turbocharge adaptation efforts. We need to spur action among all nations–and make decisions that look past the next election cycle. Businesses must realize that their own sustainability and growth are intimately tied to our planetary and population’s health.

We cannot climb this mountain without greater collaboration between the private and public sectors–nor without urgent, decisive, and collective commitment at the global, national, and subnational levels to accelerate local adaptation and effectively minimize the health impacts of climate change for a healthy, climate-resilient future.

We have a choice to make. The stakes have never been higher. With the future of humanity hanging in the balance, it’s time to chart a new course.

Vanessa Kerry MD., MSc., is the co-founder and CEO of Seed Global Health (Seed), a non-profit organization focused on health systems strengthening and transformation through long-term investments and training of the health workforce. She is a critical care physician at Massachusetts General Hospital (MGH) and serves as the associate director of partnerships and global initiatives at the MGH Center for Global Health. She directs the Global Public Policy and Social Change program at Harvard Medical School.  

Paul Hudson is the CEO of Sanofi and a member of the Health Systems Task Force of the Sustainable Markets Initiative, a key initiative mobilizing healthcare CEOs and global organizations to accelerate the delivery of net zero healthcare.

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