Sunday, December 22, 2024

Storm Darragh brought gusts of close to 100mph, but the future threat may lie elsewhere

Must read

Storm Darragh is the first storm since last January’s Isha to earn a red “threat to life” warning from the Met Office.

And it has lived up to that dubious honour.

The highest recorded windspeed was 96mph (154kph) in Berry Head, Devon, and two people have died as a result of the storm.

Get the five-day forecast where you are

Please use Chrome browser for a more accessible video player

Pier in Welsh town battered by storm

While Darragh wasn’t the most intense storm in recent years, it was a monster. The extra-tropical cyclone (to give it it’s proper title) measured 1,000km (621 miles) across as it passed right over the UK.

Revolving anti-clockwise, as such storms do, it encircled our coasts with winds from the north and east with the most powerful barrelling in from the southwest.

It’s just over two weeks since Storm Bert brought widespread flooding and high winds to Wales and southern England with four named storms now in the last three months.

So, it’s not unreasonable to ask: Is the UK getting stormier?

Pic: Met Office
Image:
UK named storms. Pic: Met Office

The 2023/24 storm season was certainly a bad one with 12 named storms. The Met Office got so far down the alphabet the season ended with Lilian’s yellow warnings for rain and wind in August.

But the season before saw just two named storms. You have to go back to 2015/16, when there were 11 named storms.

The picture is messier before that date as the naming convention began in 2015, making comparisons before then impossible.

A person takes shelter under an umbrella as they cross the Sean O'Casey Bridge in Dublin's city centre. Storm Darragh is approaching the UK and Ireland and is expected to bring winds of up to 80mph and heavy rain on Friday and into the weekend. Picture date: Friday December 6, 2024.
Image:
A person takes shelter under an umbrella on the Sean O’Casey Bridge in Dublin. Pic: PA

However, meteorologists believe the 2013/14 storm season was the most severe in at least two decades.

At least 12 named storms brought major coastal flooding and the inundation of the Somerset levels with water for weeks on end.

No clear trends

In fact, a recent review of storm records, going back over four decades, has revealed there’s no clear trend between our rapidly warming planet and the frequency of North Atlantic storms.

The jet stream – the high-altitude atmospheric current that tends to steer weather systems towards us over the North Atlantic – has a complicated and so far indecipherable relationship with climate change.

Please use Chrome browser for a more accessible video player

‘It’s not Wizard Of Oz stuff’

The current best guess is that storms may get more frequent and more windy when, on current trends, the world is around two degrees warmer a few decades from now. But as things currently stand that’s an uncertain prediction.

What is clearer, is the relationship between warming and how much rain storms bring.

Average winter rainfall has been increasing across Northern Europe and simple physics help explain that.

Part of a fallen tree which has hit a car on Greenbank Road in Liverpool. Millions have been warned to stay indoors, thousands are without power and trains have been cancelled as the Government's "risk to life" alert brought on by Storm Darragh came into force. Picture date: Saturday December 7, 2024.
Image:
A tree which hit a car in Liverpool. Pic: PA

More rainfall likely as the climate warms

With every degree increase in temperature, the atmosphere can hold 7% more water vapour – water that eventually falls as rain.

And the warmer the oceans are, the more readily they give up their moisture and the more energy – in the form of heat – they can transfer to storms.

The trend in ocean temperatures – particularly in the North Atlantic over which most of our storms develop – has been stark in recent years.

North Atlantic Daily Sea Surface Temperatures 1985-2024. Pic: Climatereanalyzer.org/NOAA
Image:
North Atlantic Daily Sea Surface Temperatures 1985-2024. Pic: Climatereanalyzer.org/NOAA

Surface temperatures there in 2023/24 have tracked up to a degree or more above average in records going back to the 1980s.

Read more:
Premier League striker ‘stable’ after car crash
Storm Darragh latest – man dies and major incident declared
William meets Trump at Notre Dame reopening

As Storm Darragh moves on, we’ll get a flavour of what our wetter future feels like.

The system is dumping rain across most of the UK, even areas that were thankfully spared the worst of its lethal winds.

Latest article