Global warming has made UK heat wave at least 10 times more likely: study

Human-caused climate change has tipped the scales dramatically in favor of the record-breaking UK heatwave that hit the country last week, a a new study concludes.

Why is this important: Extreme weather and climate events play an important role in how society experiences global warming, and this study clearly lays out the current consequences of greenhouse gas emissions.

The big picture: The extreme event attribution study sought to find out how climate change due to the burning of fossil fuels and other factors is changing the chance and severity of extreme heat events in the UK.

  • He revealed that the UK heat wave, which peaked on July 18 and 19, setting a record for the hottest temperature in UK history, at 104.54°F (40.3 °C), was at least 10 times more likely to occur in today’s warmer climate compared to the pre-industrial era.
  • It also found that average heat wave temperatures were at least 3.6°F (2°C) milder than they would have been in a world without the current high atmospheric concentrations of greenhouse gases. tight.
  • On July 19, an astonishing total of 34 weather stations broke the previous national all-time temperature record, according to the British Met Office.

Between the lines: To determine the effect of climate change on high temperatures in the UK, 21 scientists from around the world used historical weather data and computer model simulations to determine the frequency and severity of such events in the current climate, after about 2.16°F (1.2°C) of global warming since the pre-industrial era.

  • This was then compared to computer model simulations of the occurrence of such a heat event in a climate lacking today’s high concentrations of greenhouse gases.

Yes, but: The study notes that it likely underestimates the influence of global warming on this event, and therefore on the likelihood and severity of similar events in the future.

  • With the heatwave in the UK as well as the extreme event in the Pacific Northwest last year, some climatologists have wondered whether their computer models underestimated the dangers of extreme events that were once unthinkable.

The plot: One complication the researchers discovered while looking at the heat in the UK is that the frequency and severity of extreme heat in Western Europe is already increasing faster than computer models predicted.

  • Models show a 3.6°F (2°C) rise in temperatures during this heatwave, but historical data shows double that.

What they say : “In Europe and other parts of the world, we are seeing more and more record-breaking heat waves causing extreme temperatures that have become hotter faster than in most climate models,” said researcher Friederike Otto. at Imperial College London which co-leads the World Weather Allocation Groupin a report.

  • “It is a worrying finding that suggests that if carbon emissions are not rapidly reduced, the consequences of climate change on extreme heat in Europe, which is already extremely deadly, could be even worse than we previously thought” , she said.

The bottom line: This new attribution study adds to growing evidence that human-caused global warming, largely due to the burning of fossil fuels for energy, is making the planet hotter and more volatile, with cascading risks of extreme events.

Teresa H. Sadler