John and Sara recently discussed in Countryfile Magazine why 2018 is a year of extremes. Why have we gone from record cold to record heat, how much is due to climate change, and what can we expect through the rest of the year?
…we’ve lurched from one extreme to the other
Heatwave – the talk of town and country
The weather might be the nation’s favourite conversation, but during this phenomenal year, it’s all people have been talking about!
It’s been a summer that’s divided us. For many, especially sun-loving holiday makers, the heatwave has been a God-send after several mediocre years. We haven’t even had to mow the lawn! But as the landscape became evermore parched, life became an endless, overheated headache for those at the sharp end of heath-fires, hosepipe bans, wilting crops and dwindling livestock feed. Even some trees were showing the strain.
High and Dry – Just like 1976?
Reaching for the record books, the heat and sunshine this summer has often been of similar intensity to 1976. The common denominator is a dome of high pressure, blocking our usual conveyor belt of moist and mild Atlantic weather. But broadbrush statements don’t paint the whole picture. For some corners of the UK, this year may have been even more extreme – the driest start to summer for well over 50 years. On the other hand,1976 saw an extraordinary 18 days running when somewhere in the UK had temperatures above 30C. This year we haven’t got out of single figures.
But there’s one key factor which made the summer of 1976 more impactful. Back then, the UK had lacked rain for over a year. When the heatwave struck, the country was already thirsty. Serious water shortages then ensued, with hundreds of livestock perishing as fodder reserves became exhausted. Dessicated crops withered before farmers’ eyes, spawning panic buying of vegetables as shop prices soared.
Climate Change – fanning the flames of attribution
Since 1976 since there hasn’t been a significant rise in the frequency of UK ‘heatwave’ summers. It’s been a lucky break! The ‘slow-burning’ long-term trends are often disguised by the shorter-term ‘noise’ that makes up our variable weather. It’s a tangled web.
But many leading scientists suggest that deadly summer heatwaves and droughts will become the norm within a few decades. And although millions of pounds have been spent to improve water supplies and repair leaks, the booming population and ever-increasing demands from industry foretell a high-stakes race ahead between supply and demand.
Triggered by ‘The Beast’
2018 has already seen its fair share of severe weather! It seems we’ve lurched from one extreme to the other, with very little ‘normal stuff’ in between.
Odd things started happening back in February. It was a sudden warming way up in the stratosphere that sent winds across the whole northern hemisphere spinning into reverse – from the top to the bottom of the atmosphere. Thanks to the ‘Beast from the East’, extreme cold and historic blizzards paralysed the country. Children rejoiced as schools were closed on the coldest March day on record. But the atmospheric aftershocks have lingered on, long since the last snowdrifts melted.
…we’ll be lurching back into the freezer unless the westerlies rediscover their ‘mojo’
Blowing hot and cold
Our normal Atlantic westerlies have gone ‘AWOL’. Instead, continental easterlies have become commonplace. While landmasses cool down much more quickly in winter, they warm up more dramatically in summer than do oceans.
And as the continent heated up, the same winds that brought such bitter cold late winter weather began to deliver blowtorch heat in spring and summer. Ever since April, the UK has basked in successive months of above normal temperatures.
It’s thought that sea temperature patterns in the Atlantic have helped this self-sustaining force-field. ’Hot and Dry’ has bred yet more ‘Hot and Dry’.
So will the continental ‘block’ keep our mild, damp westerlies at bay through the rest of the year; or will the atmospheric damn suddenly burst? In 1976, once it started raining in late August, it barely stopped until Christmas! Well, there are no clear signs of a lasting deluge yet.
We’ll see. As autumn approaches, and the continent cools again, the prospect looms that, come winter, we’ll be lurching back into the freezer unless the westerlies rediscover their ‘mojo’.
Weather, eh – never a dull moment. Come what may, it will continue to give us plenty to talk about through the rest of the year. That’s our forecast!
Read John’s latest thoughts on the weather for the next few weeks here.