Dramatic weather events in Ireland and elsewhere that marked last year shows "the fingerprint of climate change is becoming more evident", the former head of forecasting at Met Éireann has said.
Gerald Fleming, who retired from the national meteorological service last year, said the one degree rise in the global mean temperature "increases the chance of extreme events" occurring.
Mr Fleming pointed to the two “once in 30- to 40-year type events” that took place in Ireland in 2018 – the heavy snowfall in March and the unusually hot summer – as examples.
Reporting on last year’s weather, his former employers in Met Éireann said that above-average temperatures, sunshine and widespread snow in March dominated the year, along with mild and unsettled weather in December.
“The interesting thing is that the averages don’t tell the story,” says Fleming, “The southeast of the country, for example, had a very dry summer but was wet towards the end of the year, which balanced out the averages.”
Warm summer
Heatwaves from late June through to early July saw Shannon Airport recording 32 degrees on June 28th, the highest June temperature recorded in the State since 1976. However, average temperatures were only slightly up.
The unusually warm summer was offset by colder months in February, March, September and October. The lowest temperature recorded was -7 degrees on March 1st in Cork Airport during Storm Emma.
Storms such as Eleanor in January, Ali in September and Callum in October brought high winds, with the highest gust recorded at Knock airport, Co Mayo, on January 2nd at 156 km/h.
Despite the public’s concentration on storms during 2018, Mr Fleming said the year was not actually all that unusual, bar the fact that Ali’s arrival in September brought significant bad weather “earlier than normal”.
Despite the storms, it was a year of sunshine, too. Casement Aerodrome on the outskirts of Dublin had its sunniest year since 1964, while Malin Head in Donegal saw 16.5 hours on June 28th – its highest daily total since 1955.
Wetter than normal
Two-thirds of Met Éireann’s weather stations experienced a drier than average year, particularly between May and October. However, January, February and the last two months of the year were wetter than normal.
December’s figures saw higher than usual temperatures, strong winds and heavy rainfall in some areas. Mean air temperatures everywhere were above long-term averages (LTA) for the month.
Mean temperatures ranged from 6.6 degrees (2.2 degrees above its LTA) at Knock airport to to 10.1 degrees (2.1 degrees above its LTA) at Sherkin Island, Co Cork, in December.
In October, a report by the UN Intergovernmental Panel on Climate Change issued a stark warning that there are only 12 years for global warming to be kept to a maximum of 1.5 degrees.