A recent study published in the Proceedings of the National Academy of Sciences has identified regions globally that are experiencing more warming than climate model predictions. According to multiple reports, these anomalies, spanning every continent except Antarctica, have been linked to thousands of deaths, agricultural failures and severe wildfires in recent years. The research highlights challenges in understanding and modeling the physical dynamics driving these unexpected temperature extremes, raising concerns about the adequacy of current climate models in predicting regional risks.
Heatwave intensity and global hotspots
StudyLed by Dr. Kai Kornhuber, adjunct scientist at Columbia Climate School and senior research scholar at the International Institute for Applied System Analysis, the analysis analyzed data spanning the past 65 years. It identified areas where extreme heat is increasing faster than moderate temperatureAs a result the maximum temperature is breaking records.
Examples include the June 2021 Pacific Northwest heatwave, where temperatures in Lytton, British Columbia rose to 121.3 degrees Fahrenheit, causing a wildfire that destroyed the town.
According to sources, the most affected areas include north-western Europe, parts of Asia like central China and areas of Australia, Africa and South America. The most persistent signals are seen in north-western Europe, with heatwaves leading to 60,000 deaths in 2022 and 47,000 in 2023.
According to the study, extreme summer temperatures in the region are rising at twice the rate of average summer temperatures, exacerbated by the lack of widespread air conditioning.
Understanding the underlying mechanisms
Scientists attribute some of these extremes to disruptions in the Northern Hemisphere’s jet stream, which is influenced by Arctic warming. This instability has created Rossby waves, which are trapping warm air in temperate regions.
Study co-author Dr. Samuel Bartusek sheds light on the interplay of factors behind Pacific Northwest heatwaves, including vegetation drying and atmospheric heat transport. However, studies acknowledge gaps in understanding, describing some phenomena as “grey swans”, lying between predictability and randomness.