Ireland has become warmer and wetter in the last thirty years: Met Éireann publishes Ireland’s new Climate Averages for 1991-2020
- Foilsithe: 18 Iúil 2023
- An t-eolas is déanaí: 12 Aibreán 2025
Today, Met Éireann, Ireland's National Meteorological Service, publishes a comprehensive summary of Ireland's latest climate averages, for the period 1991-2020. These are the 30-year averages of observed variables such as rainfall and temperature.
The key findings from Met Éireann’s analysis of the 1991-2020 climate averages highlight changes in Ireland's climate over the past three decades. The most notable one being an overall increase in air temperature compared to the previous 30-year period with the average yearly air temperature for Ireland standing at 9.8°C (1991-2020). This represents an increase of 0.7°C. Furthermore, mean temperatures are higher across the country for all seasons in the most recent 30-year period.
The research also shows that sunshine hours have increased by approximately 5% when compared to the 1961-1990 period, with May as the sunniest month of the year followed by June.
Met Éireann’s analysis also reveals an increase in rainfall of approximately 7% over the last 30 years when compared to the 1961-1990 period, with annual average rainfall for Ireland at 1,288 mm (1991-2020). Regional variations are also evident, with the West and North of Ireland showing the greatest increases in annual rainfall.
The release of these findings by Met Éireann comes ahead of the World Meteorological Organisation's (WMO) publication of the Global Climate Averages (or Climate Normals) for 1991-2020, due to take place this August. Met Éireann contributes to the development of this global dataset through the provision of data from Ireland’s equivalent 30-year period averages.
Met Éireann Climatologist and Project Lead, Mary Curley, said:
“The publication of Ireland’s most recent climate averages allows us to assess how Ireland’s current climate compares to the previous 30-year period. We know that the atmosphere is warming and what we’re seeing at the local and national scale fits the international picture.
"Importantly, the data provides information about typical climate conditions for a particular location and is a crucial benchmark for weather and climate conditions. This serves as an important resource for Government and relevant stakeholders to enable informed decision making to benefit society.
"While these averages give us an up-to-date baseline to compare our current and future weather to, it’s important to remember that weather patterns can vary significantly from year to year.”
The findings in these new 30-year averages align with the results from Met Éireann’s TRANSLATE climate projections, optimised for Ireland, which were released in June. TRANSLATE confirms the likelihood of a warmer and wetter climate annually for Ireland, in relation to future potential global warming under different green-house emission scenarios.
Met Éireann will publish a comprehensive technical report on the 30-year averages 1991-2020 on met.ie later this year, which will provide more detailed information.
Notes
About Met Éireann
Met Éireann, the National Meteorological Service, monitors, analyses and predicts Ireland's weather and climate, supporting Irish society and decision-makers with world-class weather, climate and flood services. Met Éireann does this to protect life and property, and to promote wider societal and economic wellbeing.
Met Éireann’s overarching vision is as follows: ‘Making Ireland weather and climate prepared - helping Irish society to be ready for and responsive to weather and climate challenges.’
Met Éireann is Ireland’s National Meteorological service as maintained by the State under the UN Convention of the World Meteorological Organisation (WMO).
About the 30-year climate averages
Met Éireann calculates and updates Ireland’s 30-year climate averages every ten years, in accordance with WMO, which mandates that each of its member nations compute these 30-year averages and recommends an update each decade. The period of 30 years is considered long enough to smooth out year to year variations.
Averages are calculated using meteorological observations collected at weather stations from the Met Éireann Observations Network, which are then quality controlled before becoming part of the weather and climate records. Then applying mathematical gridding techniques, maps are produced with values every 1 km for air temperature and rainfall.
On Ireland’s 30-year climate averages 1991-2020:
- Spring experienced the greatest temperature rise, with an increase of 0.8°C between the two average periods (1961-1990 and 1991-2020)
- whilst mean temperatures were higher in all months, the increase varied. Highest rises in temperature were seen in May at approximately 1.0°C, followed by approximately 0.9 °C in February, April and November. The smallest rise was in October (0.2°C) followed by December (0.3 °C). All other months showed a rise of between 0.6° to 0.8°C
- sunshine hours have also shown an upward trend, with approximately 5% or 63 more hours of annual sunshine than in the previous 30-year period
- May is the sunniest month of the year for the period 1991-2020 with an average total of 189.6 hours. This is followed by June (172.8 hours), April (162.1 hours), August (153.1 hours) and July (150.4 hours). December is the dullest month of the year with 44.1 hours
- Winter and Autumn have been the wettest seasons during the 1991-2020 period, with average rainfall of 380 mm and 369 mm, respectively. Conversely, spring was the driest season, with an average of 256 mm of rainfall, followed by summer with an average of 282 mm observed over the last 30-year period
- annual average rainfall has increased by approximately 7% between the periods 1961-1990 and 1991-2020. Almost all regions have observed an increase in annual average rainfall between the two 30-year periods
- annual average rainfall has increased by approximately 3-6% in the east of the country and approximately 6-12% across areas of the west and north
Ireland’s Climate Averages 1991-2020 Summary Report, story map and graphic material can be found here: https://www.met.ie/climate/30-year-averages