Our continued dependence on fossil fuels is damaging our health and pushing global temperatures to record levels. The interlinked climate calamities of the past few years - extreme weather events, food insecurity, water scarcity, and worsening air pollution - are a direct result of greenhouse-gas (GHG) emissions. But the adverse effects we are experiencing today could be just a preview of the catastrophes that await us.

That is the key finding of the latest Lancet Countdown report on climate change and health, authored by a group of leading health and climate scientists that I led. Undoubtedly, this grim conclusion will not come as a shock to the millions of people suffering from climate-related health issues and their loved ones. Most of us, wherever we live, are directly or indirectly affected by this crisis.

As climate change worsens, its effects on our physical and mental health are no longer hypothetical. Our research finds that, compared with 1981-2010, the increasing frequency of heatwaves and droughts over the past few years has exposed 127 million more people to moderate or severe food insecurity in 2021. Meanwhile, outdoor air pollution from the combustion of dirty fuels claims 1.9 million lives annually, and infectious diseases like dengue are expanding to new regions.

Yet, despite 27 years of annual climate-change negotiations, world leaders still refuse to acknowledge the urgent need to phase out fossil fuels. Despite overwhelming evidence that fossil-fuel combustion is the primary driver of the current health crisis, a draft statement on climate change and health, set to be released during the upcoming United Nations Climate Change Conference (COP28) in Dubai, omits any reference to the issue.

With many countries and companies backtracking on their climate commitments, the world is moving in the wrong direction. At the current rate of GHG emissions, we are heading for a global temperature increase of nearly 3° Celsius by 2100, far above the 1.5°C target established by the 2015 Paris climate agreement.

The consequences could be catastrophic. Even with a global mean temperature increase of just under 2°C, annual heat-related deaths are projected to increase by 370% by mid-century. The most vulnerable groups, the elderly and children, are now exposed to twice as many heatwave days as they were 30 years ago. And with heatwaves becoming increasingly frequent, the number of people suffering from moderate or severe food insecurity could increase by roughly 525 million by mid-century.

Beyond these direct effects, the climate crisis undermines individual well-being and the socioeconomic conditions necessary for a healthy population. In 2022, extreme heatwaves resulted in a loss of 490 billion working hours worldwide. Even if we manage to limit global warming to just below 2°C, heat-related labor loss is projected to increase by 50%.

It should be emphasized that these effects are not distributed evenly. The regions that have contributed the least to climate change - Africa, South and Central America, Asia, and small island developing states - often bear the brunt of climate-related health risks.

Given the urgency of the threat we face, the current pace of global efforts to reduce emissions is insufficient, falling far short of the Paris agreement's targets. Energy-based emissions hit an all-time high in 2022, while renewables still account for only 9.5% of the world's electricity. Households around the world still rely on dirty fuels. In the world's most climate-vulnerable countries, families rely on polluting fuels for 92% of their domestic energy, subjecting residents to toxic air inside their own homes.

While policymakers are tempted to address this crisis incrementally, solving one problem at a time or focusing on adaptation alone is insufficient. Without significant emissions reductions, adaptation will be futile. The climate-fueled health crisis cannot be solved without urgently shifting away from fossil fuels. By focusing on climate policies that enhance public health and well-being, governments could prevent premature deaths, build a more resilient population and a stronger workforce, and bolster their domestic economies.

How can this be achieved? Our report outlines 11 concrete measures across five priority areas. First and foremost, to ensure that climate hazards remain within the adaptive capacity of our health systems, we must reduce GHG emissions in accordance with the Paris agreement. This requires a concerted effort to phase out fossil fuels through a just energy transition that mitigates the health effects of air pollution and expands access to clean, renewable energy, especially in the world's most underserved regions, where energy poverty remains a challenge.

At the same time, we must accelerate adaptation efforts to protect communities already suffering from the health consequences of climate change by bolstering cooperation between the health sector, environmental organizations, and meteorological services. And by eliminating all subsidies, lending, and investment in fossil fuels, we can create space for climate financing and resource allocation to support adaptation efforts in vulnerable countries.

The health sector must lead this transition. Strengthening health adaptation is critical to ensuring that our health systems can protect us amid escalating climate disruptions. Crucially, we must implement public-health measures that reduce air pollution, advocate healthier low-carbon diets, encourage active lifestyles, and enforce regulations on polluting industries. And, given that the health sector itself accounts for 4.6% of global GHG emissions and has influence over roughly 11% of the world's economy, it could play a significant direct role in global decarbonization.

COP28 is a test of world leaders' commitment to tackle this crisis. A genuine focus on health could catalyze a rapid and sustained shift away from fossil fuels and facilitate adaptation efforts. Failing to do so will result in a conference that does little more than pay lip service to health concerns and validate our collective inaction. Climate-related deaths will continue to increase, and a livable future will drift further beyond reach.

From Project Syndicate