WHAT CAUSES THE HEAT WAVE?
The heat wave was caused by the build-up of high pressure over Europe in recent days, leading to the northward movement of warm air from Europe across the UK.
“At this time of year, southerly winds will always lead to above-average temperatures,” said meteorologist Peter Inness of the University of Reading.
“Air from continental Europe, the Mediterranean, and even North Africa is brought over the UK.”
“The eastern passage of weather fronts and low pressures from the North Atlantic is currently being blocked by high pressures over Europe,” added climate scientist Len Shaffrey of the University of Reading.
WAS IT RELATED TO THE US HEATWAVE?
The recent warm weather in the US was caused by a high-pressure dome that accumulated in much of the country and held the summer heat.
This has wider consequences.
“Heat wave conditions in the American Midwest and East Coast have amplified the jet stream,” explains environmental scientist Kate Sambrook of the University of Leeds.
The resulting thunderstorms that occur on the continent have helped the jet stream meander and move to the north of the UK.
“As a result of this shift, warm air has been drawn in from Europe, creating the high temperatures we experience this week.”
The warm weather in the US was caused by a high-pressure dome that accumulated over much of the country and trapped the summer heat
HOW LONG DOES THE HEAT LAST?
“While there is some uncertainty in the forecast, it looks like it will get cooler on Friday as high pressures on Europe slowly move east,” said Dr. Shaffrey.
“This will allow weather fronts to move across the UK, with cooler air and possibly some rain,” added Professor Shaffrey.
WHAT IS IT GETTING HOT?
Meteorologists predict high temperatures up to 38 ° C above central and eastern England on Thursday.
Although different forecasts expect slightly different details, “the broad message of all forecasts is the same,” said Dr. Inness.
“It will be hot, with high temperatures during the night periods, and there is a risk of thunder in the UK.”
These continue until Wednesday.
“If conditions persist, it is likely that we will experience the hottest July ever,” said Dr. Sambrook.
“The outcome is uncertain, however, as conditions are expected to change early next week.”
Climate scientist at the University of Oxford, Karsten Haustein added, “there is a 40 to 50 percent chance that this will be the hottest July ever.”
The final estimate depends on which observational dataset is used, he noted.
While he agreed that next week’s weather will set July’s place in the record books, Dr. Inness noted that 2019 brought us the hottest June known since the year 1880.
“In fact, 9 out of the 10 warmest June’s in the world record has happened since 2000,” he said.
In Europe, he noted, this was also the hottest ever this June, reaching nearly a degree Celsius above the previous number one in 2003 in 2003.
“Weather records aren’t normally broken by such large margins – a few tenths of a degree is more likely.”
The current conditions may prove to be record breaking, but they are also part of a recent trend towards warmer summers in the UK.
2018 was the joint hottest [year] with the highest temperature measured around 35 ° C, comparable to the temperatures expected this week, ‘said climatologist Declan Finney of the University of Leeds.
The odds of experiencing such hot summers have risen from a chance of less than 10 percent in the 1980s to a chance of 25 a day today, he added.
DOES CLIMATE CHANGE GIVE HEAT WAVES?
“The fact that very high summer temperatures have occurred in recent years both globally and throughout Europe is very much in line with what we expect from man-made global warming,” said Dr. Inness.
“Changes in the intensity and likelihood of extreme weather are how climate change manifests,” says environmental scientist Friederike Otto of the University of Oxford.
That doesn’t mean that every extreme event is more intense, but it does. For example, any heat wave occurring in Europe today is made more likely and intense by man-made climate change. ‘
But local factors also play a role, with any extreme weather conditions being affected by location, season, intensity and duration.
The current heat wave is not the only notable indicator of climate change, experts note, where persistent drought – as experienced in many parts of Germany – is also in line with scientific predictions.
Research into the 2003 European heat wave suggested at the time that human activity did the risk of such hot summers has more than doubled – and that annual heat waves as we experience them now can become common around the middle of the century.
“It is estimated that about 35,000 people died in 2003 as a result of the European heat wave, so this is not a trivial matter,” said Dr. Inness.
“With further climate change, there may be a 50% chance of hot summers in the future,” Dr. Finney agrees.
“That is similar to saying that a normal summer will be just as hot in the future as our hottest summers yet,” he added.