Climate change is becoming a global health emergency, Lancet Countdown report suggests

Climate change is increasingly threatening human health worldwide, with heat-related deaths, droughts, and other climate-related risks rising faster than global efforts to tackle the crisis, according to the latest Lancet Countdown report published ahead of COP31

The 2026 report, developed by an international team of researchers in collaboration with the World Health Organization (WHO), highlights the growing impact of climate change on public health and calls for urgent action to protect communities.

Heat-related deaths on the rise

The report finds that annual average heat-related deaths rose nearly 36% in the years following the Paris Agreement, compared with the previous decade.

In 2023, heat was linked to a record 710,000 deaths globally, with more than 70% of these deaths attributed to human-caused climate change. Rising temperatures are also worsening drought conditions, increasing exposure to extreme water-related events, and driving significant economic losses.

The findings underline how climate change is becoming an increasingly serious health threat, affecting communities worldwide and putting additional pressure on healthcare systems.

Clean energy offers hope

Despite the growing risks, the report highlights progress in tackling climate change and reducing its health impacts.

Global investment in clean energy reached a record $2.1 trillion in 2025. Countries that have reduced fossil fuel-related air pollution are also estimated to be preventing thousands of premature deaths each year.

Other positive developments include greater adoption of national health adaptation plans and the expansion of climate-informed early warning systems. These measures can help communities prepare for extreme weather events and reduce their impact on public health.

The report emphasises that climate action can deliver immediate health benefits, particularly through cleaner energy, improved air quality and stronger healthcare services.

Researchers suggesting global action

Researchers are calling on the global community to recognise and address climate change as a health emergency formally. They also recommend making health considerations central to decisions on climate policies, adaptation strategies, and funding.

Key priorities include reducing greenhouse gas emissions, increasing financial support for climate adaptation and investing in healthcare systems that can withstand climate-related pressures.

The WHO is already working with countries to strengthen health surveillance, improve early warning systems and develop climate-resilient healthcare services. It also supports international cooperation through the Alliance for Transformative Action on Climate and Health, which brings together health ministries and partners.

Preparing for future climate risks

The WHO is also coordinating a graded emergency response to the expected health impacts of the ongoing El Niño event, bringing together expertise and support for countries most at risk.

Published a decade after the Paris Agreement entered into force, the 2026 Lancet Countdown report brings together 146 researchers from more than 100 institutions across over 30 countries.

As countries prepare for COP31, the findings highlight the need for stronger international cooperation to address climate change’s health consequences. While progress is being made, the report warns that faster, more ambitious action is essential to protect lives, strengthen health systems, and build more resilient communities.