How hot was Scotland in 2023, the global hottest year?

Since June, according to the European Union’s Copernicus Climate Change Service (C3S), every month has been the hottest on record compared with the corresponding month in previous years. These extraordinary temperatures are believed to be a result of a combination of human-induced climate change and the effects of El Nino.

C3S director Carlo Buontempo described 2023 as “in a league of its own, compared to other very warm years.”

But what did that mean for Scotland? In the midst of this global hottest year on record, what kind of weather did we have?

Last week the Met Office confirmed that preliminary data showed it was the second warmest year in the UK, and the warmest on record in Wales and Northern Ireland, with a mean temperature of 9.97C.

According to a study by Met Office scientists found, that 9.97C would have been around a 1-in-500 year event in a climate unaffected by humans.

Many in Scotland may remember a wet July. As the temperature soared in southern Europe, and alerts were issued, the UK had a month that was, as the Met Office put it, “unseasonably wet and windy”.

But record-breaking heat was nevertheless part of Scotland’s 2023. In June, temperatures, the Met Office noted, were above average in all areas of the UK, with “parts of western Scotland having mean maximum temperatures as much as 4 °C above average”.

2023 mean temperatures compared to average (Image: The Met Office)

Threave in Dumfries and Galloway reached 30.7C on June 12, the highest temperature of 2023 in Scotland.

By the end of that month, five areas of Scotland were at the highest level of water scarcity alert – among them Loch Maree, rivers Annan and Nith, the Black Isle and Western Isles.

That drought wasn’t created solely by the searing heat of June. Also to blame were the low levels of rain in a spring in which the Highland region of Scotland saw its eighth driest May since 1890. Rainfall totals for spring were also below average for northwest Scotland.

July in Scotland may have been wet and windy, but September brought a fresh heatwave, and the third warmest September on record, with an average mean temperature of 12.8°C. Only 2021 and 2006 were warmer for the country.

2023 sunshine compared to average (Image: The Met Office)

Climate change may also have been behind some of Scotland's more extreme weather events. Though studies have not yet demonstrated that climate change was responsible for individual storms, we do know that warming increases the frequency of extreme weather events.

In the hottest ever year, storms lashed Scotland and blocked roads and, in May, the Cannich wildfire burnt through 6 square mile of the Highlands, including the RSPB Corrimony nature reserve.

Scotland’s stand-out meteorological event of 2023, in Babet, a storm in which two weeks of rain was seen in hours. As the Met Office put it: “Scotland bore the brunt of Atlantic frontal systems and associated rainfall. This included some exceptionally wet weather on 6th and 7th from an 'atmospheric river' event. Scotland overall received 64.1mm in these two days, making this its wettest 2- day period on record.”

Emergency services help a man to safety at Brechin during Storm Babet

Dramatic scenes swamped the news and social media: giant hay bales swept along the River Aray; cars marooned in the flooded car park at Oban Tesco; the A9 running like a causeway between fields of water; landslides covering the A83 and A85. People were airlifted to safety, crops were destroyed, roads cut off, basements flooded, and two people tragically died.

Whether Storm Babet, and some of the other weather events of 2023, can be attributed to climate change has not yet been determined, but what research has shown is that such extreme events are likely to become more common as the world heats.

However, across Scotland as a whole, this was merely a year of average rainfall.

Stephen Dixon, Met Office Spokesperson said: "Scotland had its third warmest year on record according to mean temperature in a series from 1884. It was also the ninth sunniest year on record for Scotland in a series from 1910.

"In terms of rainfall, Scotland as a whole has rainfall amounts very close to average, though some of those in the north and west had slightly less rainfall than average.

"Climate change is influencing Scottish temperature records, as they are for the UK. Climate change is making warmer weather more frequent and longer lasting, which can be clearly seen in the Met Office’s observations.

"For Scotland, the three warmest years on record have all occurred since 2014, with just one of the top ten warmest years on record happening before 2000 (1997)."

READ MORE: Scotland's marine heatwave explained: from data to jellyfish

But it was not only the air that was warm; it was also the sea. One of the most severe marine heatwaves on the planet developed off the coast of Ireland and the UK, with water temperatures reported off Scotland as high as 4-5°C above normal.

It was so anomalously warm in our famously chill waters that the National Oceanic and Atmospheric Administration’s (NOAA) Marine Heatwave Watch categorised this as a Category 4 (extreme) marine heatwave.

What scientists see as remarkable about this global hottest year is that the heat arrived earlier than expected in this current El Nino phase – the full impact had not been expected till 2024.

Can we expect more extraordinary heat this year? El Nino is still with us, and the Met Office outlook suggests that global temperatures this year will exceed those of 2023. The Met Office has predicted we could even temporarily breach the limit of 1.5C above pre industrial levels to which the world agreed to attempt to limit warming, this year. “For the first time, we are forecasting a reasonable chance of a year temporarily exceeding 1.5°C,” said Dr Nick Dunstone at the Met Office.

READ MORE: Scotland weather: From Hottest June to Storm Babet

More marine heatwaves are also expected in coming years. Professor Michael Burrows, a world expert on marine heatwaves working at the Scottish Association of Marine Science said: “Marine heatwaves are becoming more frequent and more intense. Climate change is likely to make everything much worse, till the point that at some point in the next five or six decades, we will be in a permanent heatwave”.

Meanwhile, reports published in 2023 by the James Hutton Institute, revealed that Scotland’s climate is changing faster than predicted, with changes expected to be seen over the next three decades already happening now. “Climate extremes,” one of the reports said, “have already changed and are projected to increase: longer dry periods; heavier rain in winter."