New research shows that limiting warming to 1.5°C would reduce the frequency of extreme heat and rainfall across Europe.
This is compared to a previously sought 2°C limit to global warming. Many scientists now say a 2°C cap is not enough, and would place extreme stress on many of the world’s most sensitive ecosystems. A 0.5°C difference may seem insignificant, but it could make all the difference in avoiding record-breaking heat waves.
Researchers at the University of Melbourne and the University of Oxford used simulations—called coupled climate models—to show that 1.5°C of global warming would make extreme heat waves in Europe less likely to occur.
“For example, we found that events similar to the European heat wave of 2003, which caused tens of thousands of deaths, would be 24% less frequent in a world at 1.5°C global warming compared to 2°C global warming,” say the researchers.
Changes in rainfall were also included in the climate models. Although the changes are less pronounced compared to warming, they could still have major consequences for European countries.
“There is an increase in the frequency of very wet days like those seen during May–July 2007 over the UK and Ireland. In a 2°C world, such extreme rainfall events are at least 17% more likely than in a 1.5°C world.”
In England alone, the economic cost of damage to property from the Summer 2007 floods was estimated at $4 billion. If a 2°C threshold is reached, Europe could expect flooding damage like this once every 10 years.
The Paris Agreement—an international effort to keep global warming below 2°C and to attempt to cap the warming further to 1.5°C—has recently sparked a wave of studies examining what’s needed to achieve this cap. Many of these studies now suggest that negative emissions, removing carbon dioxide from the atmosphere, are needed to keep global warming below 2°C, which is becoming increasingly unlikely.
This failure to limit global warming could have considerable consequences for Europe.
“In future scenarios of 1.5°C and 2°C warming, heat extremes become considerably more frequent,” the authors of the current study say. “Even at only 1.5°C of warming we estimate that hot years across Europe, like 2016, the hottest year on record, would happen roughly one-in-every-two years.”