An unprecedented and relentless heatwave, exacerbated by climate change, has gripped southwestern parts of the United States, Mexico, and northern Central America, leading to over 100 fatalities in Mexico alone. This extreme heat event, driven by a persistent high-pressure system known as a heat dome, has shattered daytime and nighttime temperature records across the region, including Mexico, Guatemala, Honduras, and the southwestern United States.
The heat dome phenomenon, which traps hot air near the ground and intensifies under clear skies and sunshine, has resulted in severe and widespread impacts. Mexico has reported 125 heat-related deaths since March, with the ongoing drought conditions further aggravating the situation. The drought has not only reduced water availability but also impaired the dispersion of pollutants and decreased hydropower generation, leading to power outages and further stressing the already vulnerable infrastructure.
In a collaborative study, scientists from Mexico, Panama, the Netherlands, the United Kingdom, the United States, and Sweden analyzed the extent to which human-induced climate change has influenced the likelihood and intensity of this extreme heatwave. Using peer-reviewed methods, the researchers focused on 5-day maximum daytime and nighttime temperatures recorded in May and June over a vast region encompassing the US southwest, Mexico, Guatemala, Belize, Honduras, and El Salvador.
The study’s main findings reveal a stark reality:
- The extreme heat has resulted in more than 125 heat-related deaths in Mexico, numerous heat stroke cases, and significant economic disruption due to power outages.
- Current observations indicate that 5-day maximum temperatures of this magnitude, which were expected once every 60 years around the year 2000, are now anticipated to occur every 15 years due to the 1.2°C rise in global temperatures.
- Nighttime temperatures, while not as extreme, have become more frequent, with a 50% chance of occurrence each year, up from a 13% chance at the turn of the millennium.
- Climate models indicate that human-induced warming has made these 5-day maximum temperature events about 1.4°C hotter and 35 times more likely, while nighttime temperatures are about 1.6°C hotter and 200 times more likely.
The study underscores the urgent need for comprehensive heat management strategies. Experts recommend the implementation of extreme heat warning systems and action plans to enhance preparedness across Central America. Protective laws for outdoor workers, improved urban planning with more green spaces, and enhanced infrastructure in informal settlements are crucial measures to protect the most vulnerable populations.
Moreover, strengthening grid resilience and promoting water conservation strategies are essential to ensure reliable services during heat events. As climate change continues to drive such extreme weather events, the study highlights the necessity for robust and coordinated efforts to mitigate their impacts and safeguard public health and infrastructure.
This research, published by the World Weather Attribution, provides a critical understanding of the role of climate change in intensifying heatwaves and calls for immediate action to address the growing threat posed by extreme heat events.