Study shows west Mayo coastal communities most exposed to climate-related hazards

Coastal communities across west Mayo are most exposed to climate-related hazards including rising sea levels and storm surges according to university researchers.

A new map developed by researchers at University College Cork has shown that communities living along Blacksod Bay and Clew Bay are most at risk to climate-related hazards.

The first national map of Ireland’s exposure to climate hazards, including rising sea levels and storm surges, has identified the stretches of coastline facing the greatest pressures, providing critical new evidence to support coastal management and climate adaptation.

The research, led by University College Cork (UCC) researchers, assessed approximately 8,575 km of Ireland’s coastline at 250-metre intervals, bringing together 30 years of wind and wave data with information on sea-level rise, storm surges, shoreline type, coastal relief and natural habitats.

The study has developed the ‘Coastal Exposure Index for Ireland’, which provides, for the first time, a consistent national-scale assessment of exposure around Ireland’s coast and identifies areas where people, cultural heritage and other coastal assets are particularly exposed.

The research shows that Mayo has the largest stretch of coastline classified as “Very High Exposure”, at 414.5 km with much of the Mullet peninsula coming under this category as well as areas around Geesala, Doohoma and Ballycroy.

Parts of Achill and the Currane peninsula are also identified as areas of very high exposure along with large parts of the coastline around Carroniskey beach near Louisburgh. Parts of Westport and Kilmeena are identified as areas of very high exposure as well as high and moderate exposure.

The north coast of Mayo is not as exposed as the west with the majority of areas identified as low or very low exposure areas.

The UCC researchers say the study provides a new evidence base for identifying communities where more detailed local assessment and climate adaptation planning is needed.

While solutions to coastal erosion in Ireland have historically involved hard, engineered structures such as rock revetments, sea walls and groynes, researchers say this study illustrates the critical role of natural coastal habitats in reducing exposure to climate hazards for both communities and cultural heritage.

Sand dunes, saltmarsh, machair and seagrass have the potential to reduce exposure along 38 percent of Ireland’s coastline, by lessening the intensity of wave impact, stabilising shorelines and adapting to sea level rise.

Study lead Kevin Walsh, geoscientist and researcher in the DETECT (Digital Environmental Technology for Enhanced Coastal Zone Management) project at UCC, said: “This research gives us, for the first time, a consistent picture of relative climate exposure right around Ireland’s coastline. What is particularly clear is that exposure varies considerably from place to place, meaning effective adaptation must take account of local coastal conditions.

“Our findings underline the significance of Ireland’s natural coastal habitats as a critical line of defence against climate hazards. Dunes, saltmarshes, machair and seagrass can help protect our coastline, communities and heritage from growing climate pressures. Protecting and restoring these habitats must be a priority in Ireland’s coastal adaptation response, alongside other approaches to coastal adaptation.”

The researchers say the national Coastal Exposure Index can help government, policymakers, local authorities and coastal communities identify areas that may require closer assessment and support the prioritisation of adaptation measures and resources.

Dr Aaron Lim, Senior Lecturer in Marine Geosciences at UCC College of Arts, Celtic Studies and Social Sciences and Head of the Earth and Ocean Lab, said: “This research gives Ireland a unique opportunity to be proactive rather than reactive. For the first time, we can identify where exposure to coastal climate hazards is greatest and use that evidence to guide national strategy and targeted regional action.

“The decisions we make over the coming decade will shape how well our communities, infrastructure, businesses and cultural heritage can adapt to rising seas, coastal flooding and erosion,” Dr Lim said.

Researchers have also launched a new interactive online map – viewable online – that the public can use to explore coastal exposure to climate hazards across Ireland and better understand the risks facing coastal areas.