In July 2025, Japan experienced its hottest month on record, with average temperatures 2.89°C above the 1991-2020 average. This unprecedented heatwave, culminating in a national high of 41.2°C in Hyogo Prefecture on July 30, underscores the escalating challenges posed by climate change.
The extreme temperatures have had significant health impacts. The Fire and Disaster Management Agency reported over 10,000 hospitalizations due to heatstroke in the week leading up to July 30, with 16 fatalities. Vulnerable populations, particularly the elderly, have been disproportionately affected, highlighting the urgent need for effective heat mitigation strategies.
In response to the escalating heat, the Japanese government has implemented several measures. A revision to the Ordinance of Industrial Safety and Health, effective June 1, 2025, mandates employers to adopt preventive measures against heatstroke, including monitoring environmental conditions and worker symptoms when temperatures exceed 31°C. Noncompliance carries penalties of up to six months’ imprisonment or fines up to JPY 500,000. Additionally, municipalities such as Tokyo, Osaka, Fukuoka, Yokohama, and Nagoya have introduced subsidies for the purchase of energy-efficient air conditioners, supporting upgrades and new installations to help households cope with the heat.
These initiatives reflect a growing recognition of the need for comprehensive strategies to address the health risks associated with extreme heat. As climate change continues to intensify, such measures are crucial in safeguarding public health and enhancing resilience against future heatwaves.