Sea level rise and ‘storms’ threaten Ireland’s sandy beaches

Sea level rise and ‘storms’ threaten Ireland’s sandy beaches

The sandy beaches, wide open spaces and constant drama of the ever-changing coastal landscape have long drawn crowds to the world’s coasts, both as vacationers and as permanent residents.

For generations of Irish people, holidays, whether at home or abroad, have been synonymous with the seaside. Although the sun is not always guaranteed, you can at least count on sea and sand. However, recent reports paint an alarming picture of the future of our coastal regions.

According to a 2020 article in Nature Climate Change, much of the world’s sandy coastline is already eroding, a situation it says will be exacerbated by the impacts of climate change. “Ambient trends in shoreline dynamics, combined with coastal recession driven by sea level rise, could lead to the near extinction of nearly half of the world’s sandy beaches by the end of the century. “, warn the authors.

Ireland has some of the most beautiful beaches in the world, dotted along 7,400km of winding coastline. Over the past decade our rugged coastline has been marketed as a unique tourist amenity, with Fáilte Ireland spending over €110 million since 2014 to promote the Wild Atlantic Way.

The campaign has been almost too successful, with areas such as Dingle, the Burren and the Cliffs of Moher experiencing bottlenecks and capacity issues on minor country roads and lanes which can “negatively affect the experience visitors,” according to an internal Fáilte Ireland document. The impacts on local people and sensitive coastal ecosystems from the influx of large numbers of tourists can be equally problematic.

Given that beaches are, by definition, at or slightly above sea level, relentless and accelerating global sea level rise is the clearest threat, but by no means the only one. Since coastal areas have been intensely populated by humans for centuries, “many have already lost their natural ability to adapt or recover from erosion, as the backshore is heavily occupied by human settlements,” notes the study’s lead author, Dr. Michalis Vousdoukas.

Sand dune erosion on Portrane beach.  Photography: Nick Bradshaw

Sand dune erosion on Portrane beach. Photography: Nick Bradshaw

Around 20% of the Irish coastline is now threatened by coastal erosion, of which 6% is considered to be in immediate danger

Timescales for severe impacts are surprisingly short. Up to 15% of the world’s sandy beaches will face “serious erosion” by 2050, and this proportion will increase to 35-50% by the end of the century. These estimates do not include the impact of occasional shoreline retreat caused by storms, “some events of which can leave an imprint that takes decades to recover, if at all,” Vousdoukas adds.

Increases in projected storms due to global warming are already starting to become evident in Ireland, with a slew of major storms in recent years. These include Storm Darwin (2014), Desmond (2015), Ophelia (2017), Eleanor (2018), and Storm Elsa, which made landfall in December 2019.

The three months from December 2013 to February 2014 were the stormiest period in 150 years of instrumental recording in Ireland and North West Europe, as large stretches of coastline were hit by a series of powerful storms.

These recent storms, according to Dr. Eugene Farrell of NUIG’s Department of Geography, “were the most energetic in over a century of observations”. It notes that around 20% of the Irish coastline is now threatened by coastal erosion, of which 6% is considered to be in “immediate danger”.

However, only around 4% of the Irish coastline is protected to any degree by defences. It should also be kept in mind that artificial coastal defenses can actively interfere with the adaptive and retreating capacity of the coastline.

The preservation of seagrass beds can provide natural protection for coastlines.  Photography: Phil Wilkinson

The preservation of seagrass beds can provide natural protection for coastlines. Photography: Phil Wilkinson

“There is an urgent need to build resilience in our coastal regions, given that ocean climate change will produce even more extreme storms in the northeast Atlantic,” Farrell said. These impacts are exacerbated by increasing pressure from human activities, including the recent upsurge in coastal tourism.

He cites research by the Environmental Protection Agency (EPA) which used the floods in Galway as a model and predicted that future extreme flooding could cost Ireland around €1billion in damage . It is estimated that there has been a tripling of weather-related insurance events since the 1980s, a trend that is mirrored globally.

“Our coasts are pressured by the pressure of the oceans – storms – and the land, by people,” adds Farrell. After working overseas for a decade and a half, Farrell returned to Ireland in 2012 and was surprised to find that at least eight separate government departments have some degree of jurisdiction, with no overall agency responsible. .

New research published by scientists at Maynooth University in the journal Ocean Science has revealed that sea levels in the Dublin Bay region are rising twice as fast as the planet. Between 1953 and 2016, sea levels rose by nearly 70 mm, with the rate increasing in recent years.

The authors note that Dublin City Council has recently increased coastal defenses in Dublin, “allowing an average sea level rise of 40-65cm”. According to the global trajectory of greenhouse gas emissions in the coming decades, sea level in the Dublin Bay region is projected to rise by 0.3 to 0.6 m by 2100. At the Globally, the Intergovernmental Panel on Climate Change (IPCC) predicts average sea level rise this century in the range of 0.6 to 1.1 m – depending on emissions.

Gráinne Hennigan's house on Portrane Beach in North Dublin.  The house collapsed due to damage caused by coastal erosion.  Photography: Laura Hutton

Gráinne Hennigan’s house on Portrane Beach in North Dublin. The house collapsed due to damage caused by coastal erosion. Photography: Laura Hutton

An average shoreline retreat of more than 9 m will occur, resulting in a loss of 56% of the permanent beach area

In addition to the severe ecological consequences of the loss of unique coastal habitats, this will also have profound repercussions for areas heavily dependent on tourism. A study published last December in Frontiers in Marine Science of the Balearic Islands off the coast of Spain predicts the permanent loss of up to 65% of the archipelago’s famous sandy beaches.

More than a quarter of the total income of these regions comes from seaside tourism. The researchers projected that under the IPCC’s conservative RCP4.5 scenario for global warming this century, an average coastline retreat of more than 9m will occur, leading to a loss of 56% of permanent beach area.

In the RCP8.5 “worst case” scenario, almost one in five beaches in the region would disappear completely, along with the loss of 65% of the permanent beach area of ​​the remaining coastline. Among the proposals for mitigating these impacts, the authors recommend preserving the seagrass beds which provide natural protection, while encouraging the tourist industry to “rethink its economic model”.

The east coast of Ireland has experienced accelerated erosion in recent years, particularly due to storms. Given the proximity of the DART and intercity rail lines to the coast, erosion along the east coast is of particular concern to Iarnród Éireann. It published a strategic assessment report late last year which estimated that the cost of protecting five vulnerable sections of coastal railway lines against erosion could amount to €225 million.

While high-value infrastructure can be protected, at least in the medium term, from rising sea levels and increasingly powerful storms, difficult decisions remain to be made about which areas can and cannot be protected. protected.

“We know Ireland doesn’t have the money to defend the whole coastline and the reality is that the social fabric of rural communities – already torn at the seams – will completely crumble as areas are left to their own devices. themselves and are eventually abandoned for higher ground,” Farrell says.

He notes that the OPW’s mid-term future planning scenario calls for sea level rise of around 0.5m by 2100, but he fears the actual figure could be “two to three times this estimate, which means we urgently need to refine our sea level and storm surge models.” for the country”.

The reinforced concrete units along Portrane Beach are designed to reduce the force of waves impacting the coastline during stormy conditions.  Photography: Nick Bradshaw

The reinforced concrete units along Portrane Beach are designed to reduce the force of waves impacting the coastline during stormy conditions. Photography: Nick Bradshaw

The coast remains the red-haired son-in-law that no authority or service wants

The challenge for the scientific community, Farrell argues, is to convince the government that so-called environmental goods and services “must not be taken for granted and are not free to use”.

While accepting that it is problematic to assign a strict monetary value to nature, he believes that it is also necessary. Research in the UK on its coastal regions puts their economic value at over €55 billion. Farrell’s own rough estimate of equivalent values ​​for Ireland is said to be over €2.5 billion.

However, the lack of clear planning and coordination means, according to Farrell, that “the coast remains the red-haired son-in-law that no authority or service wants”.

John Gibbons is an environmental writer and commentator

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