Waves & surges
Storm surges, particularly in combination with extreme waves, pose an ever-increasing risk to Ireland. However, projections of changes in storminess and extreme wave heights are uncertain.
Observed change
- Increasing wave heights have been observed over the last 70 years in the North Atlantic with typical winter season trends of increases up to 20 cm per decade, along with a northward displacement of storm tracks.
- Seasonal variations in wave heights are observed at buoys deployed off the coast of Ireland, however no comprehensive analysis of wave parameters has been carried out on these data.
- Storm surges, particularly in combination with extreme waves, pose an ever-increasing risk to Ireland, including major cities such as Galway, Cork and Dublin. Both Galway and Dublin have experienced significant wave overtopping in recent years, and Cork has experienced repeated nuisance flooding at high tides.
Projected change
- Significant wave heights (the highest third of all waves) are projected to decrease around Ireland during the remainder of the century. However, the future behaviour of extreme waves around Irish coasts is considerably less certain, with studies showing everything from decreases to increases in wave heights
- Expected surge levels for events of a 20 to 30-year return period are likely to increase by up to 9cm by 2100.
Resources
Ireland’s Climate Change Assessment Volume 1: Climate Science- Ireland in a Changing World 2024, Noone et al.: climate observations report
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 projections report
The impact of climate change on storm surges over Irish waters, Wang et al.: climate projections report