Climate Change Adds Month of Extreme Heat for 4 Billion Worldwide

A recent report by World Weather Attribution, Climate Central, and the Red Cross reveals that human-driven climate change caused nearly half of the global population—about 4 billion people—to endure an additional month of extreme heat between May 2024 and May 2025. The analysis found that the number of extreme heat days has at least doubled in 195 countries and territories, with all 67 major heat events recorded in the past year made more severe by anthropogenic climate change. These intensified heat conditions have led to increased illness, death, crop losses, and stress on energy and healthcare systems worldwide, with particularly severe impacts in regions like the Caribbean, where Puerto Rico experienced 161 days of extreme heat compared to 48 without climate change. Experts emphasize that heat remains the deadliest climate-related hazard and call for urgent action including restructuring energy systems toward renewables, implementing better early warning systems, heat action plans, and long-term urban planning to mitigate risks. The findings underscore the pervasive and escalating threat of climate change-induced heat waves across the globe, highlighting the need for immediate policy and societal responses.