Unraveling the Unprecedented Impact of Human-Caused Climate Change on Devastating Heat Waves Across the Globe
Extreme heat waves that have scorched parts of the United States, Europe, and China this month were found to have been significantly more likely due to the human-caused climate crisis, according to a recent analysis. The World Weather Attribution initiative, comprised of international scientists studying the role of climate change in extreme weather events, conducted a rapid attribution analysis, revealing that the blistering "heat hell" experienced in the United States and southern Europe would have been nearly impossible without climate change.
The team spent a week examining the July heat waves that have wreaked havoc across three continents, devastating crops and livestock, igniting wildfires, intensifying water stress, and tragically claiming lives. Death Valley saw temperatures reaching a scorching 128 degrees Fahrenheit (53.3 Celsius), while Phoenix endured a record-breaking 25 consecutive days of temperatures surpassing 110 degrees Fahrenheit (43.3 Celsius).
China experienced an unprecedented national high temperature of 52.2 degrees Celsius (126 Fahrenheit), and in Europe, local records were shattered in parts of Spain and Italy, with temperatures approaching Europe's all-time record of 48.8 degrees Celsius (119.8 Fahrenheit).
To assess the impact of the climate crisis on this month's extreme heat, the WWA team compared current weather data and computer models with the climate of the pre-industrial era, which is now approximately 1.2 degrees Celsius warmer. The findings were striking, with the role of climate change being described as "absolutely overwhelming" by Friederike Otto, a senior lecturer in climate science at the Grantham Institute for Climate Change and the Environment at Imperial College London.
Had humans not contributed to global warming through the burning of fossil fuels, these searing heat waves would be exceedingly rare occurrences. However, the continuous use of fossil fuels has rendered them no longer unusual but, rather, increasingly frequent.
According to the analysis, in today's climate, extreme heat waves like those experienced this July are expected to occur once every 15 years in the US and Mexico, once every 10 years in Southern Europe, and once every five years in China.
Moreover, climate change not only raised the likelihood of these heat waves but also amplified their intensity. The report indicates that planet-heating pollution made Europe's heat wave 2.5 degrees Celsius hotter, the North American heat wave 2 degrees Celsius hotter, and China's heat wave 1 degree Celsius hotter.
The situation could worsen significantly if global average temperatures rise to 2 degrees Celsius above pre-industrial levels. In such a scenario, extreme heat waves might occur every two to five years, according to the report.
While the developing El Niño likely played a minor role in raising temperatures, the primary reason for these severe heat waves is global warming resulting from the burning of fossil fuels.
The study's authors emphasize that the findings are not evidence of "runaway warming" or "climate collapse." They assert that there is still time to secure a safe and healthy future, but urgent actions are needed, such as ceasing fossil fuel consumption and investing in vulnerability reduction. Failure to take such steps would lead to tens of thousands of heat-related deaths each year.
Heat waves are among the deadliest natural hazards, as demonstrated by the devastating impact of last year's record-breaking heat wave in Europe, which claimed over 61,000 lives due to heat-related causes.
Countries and cities must swiftly reduce planet-heating pollution and implement adaptation measures in health, urban planning, and energy systems. Accelerating the rollout of heat action plans is essential to prepare for the extreme heat that the climate crisis has already locked in.
Richard Allan, a professor in climate science at the University of Reading in the UK, who was not involved in the study, explains that while fluctuating weather patterns determine the location and timing of heat waves, climate warming is exacerbating moderate heat waves and turning what would have been major heat waves into events that would have been virtually impossible without the heating effects of fossil fuel greenhouse gas emissions.
