Surface air temperature

Average surface air temperatures are expected to increase everywhere and across all seasons.

An increase in the intensity and duration of heatwaves is expected.

Ireland is broadly consistent with global changes owing to our geographical situation between Europe (which is warming considerably faster than the global mean) and the North Atlantic (which is warming at a slower rate).

 

Observed change

• Observations indicate an increase in the surface air temperature for Ireland of 1.0°C from the early 1900s to 2022.
• From 1900 to 2022 16 of the top 20 warmest years have occurred since 1990.
• The number of warm spell days has increased over the last 60 years while the number of frost days has decreased.

 

Projected change

• Mean air temperatures are expected to increase everywhere and for all seasons relative to the present.
• With increasing air temperatures, an increase in the intensity and duration of heat waves is expected, with a coincident decrease in the occurrence of frost days likely.
• For example, projections indicate that the number of heatwave events will increase by up to 15 under the RCP 8.5 scenario (high emissions scenario) for the period 2041-2060 when compared with baseline period 1981-2000. 

Scenario	Mid-century (2041–2070)
Early action	0.44°C - 1.10°C
Middle action	0.66°C - 1.77°C
Late action	1.18°C - 2.10°C

Projected increases in temperature for Ireland for the period 2041-2070 relative to 1976-2005 [source: TRANSLATE, O’Brien and Nolan, 2023]. Projected changes account for low (RCP 2.6 pathway), low-medium (RCP 4.5 pathway) and high (RCP 8.5 pathway) emissions scenarios.

Scenario	Late-century (2071–2100)
Early action	0.34°C - 1.07°C
Middle action	1.05°C - 2.21°C
Late action	2.02°C - 3.49°C

Projected increases in temperature for Ireland for the period 2071–2100 relative to 1976-2005 [source: TRANSLATE, O’Brien and Nolan, 2023]. Projected changes account for low (RCP 2.6 pathway), low-medium (RCP 4.5 pathway) and high (RCP 8.5 pathway) emissions scenarios.

 

Resources

Climate status report for Ireland 2020, Camaro & Dwyer: climate observations report

Ireland’s Climate Change Assessment Volume 1: Climate Science- Ireland in a Changing World 2024, Noone et al.: climate observations report

High-resolution Climate Projections for Ireland - A Multi-model ensemble approach 2020, Nolan & Flanagan: climate projections report

Ireland’s Climate Change Assessment Volume 1: Climate Science- Ireland in a Changing World 2024, Noone et al.: climate projections report