Extreme weather will hit the UK more frequently due to the climate crisis, scientists said after data showed last year was one of the hottest, as well as one of the wettest and the sunniest ever.
Last year was the first to make the top 10 for heat, rain and hours of sunshine, in records stretching back over a century, as moderate British weather is quickly becoming a thing of the past , according to a Met Office report. and climatologists.
The extremely sunny start to the lockdown in spring 2020 followed the wettest February, while a heatwave in August combined to make 2020 the third warmest year, the fifth wettest and the most humid. eighth sunniest on record, according to UK State Climate 2020, published in the International Journal of Climatology.
Mike Kendon, senior climatologist at the Met Office National Climate Information Center and lead author of the study, said: “The UK’s climate is already changing. The warming we are seeing is broadly consistent with what we are seeing in the world … and our climate seems to be getting wetter and warmer, and this is consistent with our broad understanding of the process. [of climate change]. «
UK weather records go back centuries in some cases, with a series of temperatures for central England dating back to 1659 and other unbroken line temperature records from 1884, and precipitation dating back to 1862, and in some cases later. The report’s authors merged the data from these series, along with sea temperatures and levels, and compared them with results from last year.
According to them, the last 30 years (1991-2020) is 0.9 ° C warmer than the previous 30 years (1961-1990), and the UK has been 6% wetter on average during of the most recent period.
Globally, land temperatures are about 1.2 ° C warmer than in pre-industrial times. Governments will meet in Glasgow at the UN’s Cop26 climate summit in November to try to agree on a way to prevent the world from heating more than 1.5 ° C above levels pre-industrial.
However, the average weather is only part of the picture: Scientists are particularly concerned that the weather in the UK is getting more and more extreme. Last year, Storms Ciara and Dennis hit just a week apart and brought precipitation that in some places was more than four times the historical monthly average.
Kendon said, “We are seeing a continuing emerging pattern of higher temperatures and more extreme precipitation. The basis of our climate is changing and what we consider normal is changing. “
William Collins, professor of meteorology at the University of Reading, who was not involved in the report, said: “The weather in the UK is likely to become even more extreme as global temperatures rise. Governments have pledged to continue their efforts to limit temperature increases to 1.5 ° C. Failure to do so will result in global climate impacts, and we will not be immune in the UK. “
As the planet warms under the influence of greenhouse gases, the warming air can hold more moisture, making the UK climate much wetter than in the past.
Richard Allan, professor of climatology at the University of Reading, explained: “Very wet periods and associated flooding become more severe as higher levels of greenhouse gases warm the air, increasing the humidity that feeds storms. A thirstier atmosphere also dries up the soil more effectively, intensifying the already hotter periods and making our weather more extreme. “
These extremes are likely to cause serious problems, as most infrastructure in the UK has not been built to tolerate the kind of precipitation, scorching temperatures and storms that are likely to strike more frequently. Flooding has hit the UK again in recent days after a heatwave earlier this month raising questions over the UK’s ability to cope with extreme weather conditions.
Liz Bentley, executive director of the Royal Meteorological Society, which published the article, warned of the danger of the weather getting warmer through ‘rose-tinted glasses’, focusing on global warming, and said the extremes of heat and precipitation would cause many problems. .
“When we saw the episodes of extreme heat last summer the roads were starting to melt, on the rail network the rails started to warp, so all trains have to slow down and we see a lot of cancellations and postponements. The electrical wiring is also starting to warp, so we are seeing power outages, ”she said. “The impacts that this will have on our daily life [mean] it will start to have a much more negative effect than just a hot, sunny day.
The impacts are also visible in agriculture and on the natural world. The first leaves appeared much earlier and fell much earlier than usual last year, according to the report. These effects can wreak havoc on other species, which may become out of sync – for example, caterpillars and other invertebrates may peak before the chicks are born, leaving them with little to eat.
Darren Moorcroft, Managing Director of the Woodland Trust, said: “If a species becomes out of sync, it can lead to a breakdown in food chains, and subsequently species that struggle not only to survive but also to thrive. “
Sea level rise has also doubled since the start of the last century, from 1.5 mm per year to over 3 mm per year, or 2 cm per decade over the past 60 years. Ed Hill, director of the UK’s National Oceanography Center, said: “An immediate consequence will be extreme sea level rise during high tides and storms that cause flooding.