Climate change must be declared a ‘global health emergency’, says Lancet study

The Lancet Countdown's 10th report reveals that climate change has resulted in three million heat-related deaths worldwide between 2016 and 2023, a figure equivalent to the entire population of Wales being wiped out in eight years. Published ahead of the COP 31 climate summit, the study, led by 146 researchers from 30 countries, highlights that 68% of these deaths are directly attributable to climate change.

Since the 2015 Paris Agreement, heat has caused a record 710,000 deaths in 2023 alone. Marina Romanello, the executive director of the health and climate research project Lancet Countdown, emphasizes the need to declare climate change a global health emergency to shape governments' policies. She calls for an integrated, long-term approach to build resilience and capacity, rather than responding to emergency after emergency.

Warming has also cost the global economy over $1 trillion annually over the past three years, with the hardest-hit regions being Southeast Asia and Africa, which lost 3.9% and 3.2% of their GDP, respectively. However, there have been some positive developments, such as 56 out of the 194 WHO member states adapting their health and early-warning systems since 2016.

Moreover, investment in clean energy reached $2.1 trillion in 2025, doubling the amount invested in fossil fuels, which are responsible for 80% of global energy and 2.73 million deaths per year due to air pollution. Despite this, only 16% of climate-related medical research funding goes to the least developed nations, which are the most affected by climate-related health threats.