Climate Change: Northern Ireland and the rising sea

The International Congress Centre in Katowice, Poland is hosting  COP24, the annual gathering of the 195 nations who signed up to the Paris agreement on climate change. Their purpose is to finalise the rulebook for delivery of the agreement, and to push on with implementation.

It takes place against the backdrop of a series of extreme weather incidents across the globe, increasingly apocalyptic scientific papers on the impacts of global warming, the impending annihilation of many species and the president of the United States of America in climate change denial.

It has reached a point where some commentators are claiming that we have left it too late and that the planet is already heading for climate catastrophe .

Whatever the truth of this the consequences of climate change are inescapable and already happening. One of the most tangible impacts is rising sea levels. Already many parts of the world are suffering, and Ireland will be no exception.

Rice farmers are abandoning the once productive paddy fields of the Mekong Delta, Vietnam now polluted by sea water. Thousands are leaving the Mekong every year. They represent a new class of homeless: climate refugees. There will be many more in many states in the decades to come.

And the city of Miami is ploughing hundreds of millions of dollars into elevating roads, improving sea defences and investing in more stormwater drainage systems. Up to a million Florida homes, worth a combined £290 billion are potentially at risk of tidal flooding by the end of the century, according to recent surveys.

Meanwhile in Antarctica scientists are increasingly alarmed by signs that an ice monster is awakening. The remote and inaccessible Thwaites Glacier is 300 miles long and 200 miles wide, larger than the island of Ireland. It is beginning to accelerate in its path to the sea, the consequences of this are as yet unknown.

Back home the situation is complicated by the fact that a northern section of Ireland’s land, roughly corresponding to Northern Ireland is actually rising. This is caused by post glacial rebound.

During the Ice Age the northern part of the island was covered by a massive sheets of ice up to 3 kilometres thick. This literally pushed down the land beneath, causing it to sink. After the ice melted, the land slowly started to rise again and as a result the area around Belfast is rising up at around 0.4 mm per year.

However the sea is rising at a rate of 3.4 mm per annum around the Irish coast, meaning that our net rise in levels is around 3 mm per year.

This might be consolation for people in coastal areas in the north, the reverse is true for the south, especially the south west of Ireland where the rate of rise will be considerably faster.

But it does not mean that there will be no impacts for the north, just that they will take longer to manifest.

What will happen is that coastal flooding will increase, as will coastal erosion. Presently around 20% of our shorelines experience coastal erosion, as compared with 12% for Scotland, another country which is literally rising. England, in contrast, is already under siege – 30% of its coast is eroding.

The combination of higher sea levels and erosion is very bad news for those who enjoy going to the beach. Between 100 and 300 hectares of our 16 beaches will disappear by 2080. Few will be able to move back naturally because of the roads and other infrastructure that are behind them. Murlough Bay is likely to lose most of its glorious sand dunes and there could even be a threat to our greatest natural treasure the Giants Causeway. Its owners the National Trust are monitoring the area closely. There has already been considerable erosion in the vicinity and there is concern that ultimately the World Heritage site might become more difficult to access.

Northern Ireland is fortunate in not having too many primary roads close to the coast. But this will not be any consolation to residents of the Ards Peninsula. Already both by Strangford Lough and the Irish Sea there are roads that become treacherous, and sometimes impassable following strong winds, high tides and heavy rain. In 2014 widespread damage was caused on both coasts by the flood of that year.

Risks to Belfast – already at high risk of flooding – will also increase with the potential for devastating tidal floods as well as those caused by heavy rain.

We may be better placed than other parts of the worls, but that does not mean we will not get off  lightly. Sea level rises are inexorable and will continue to rise for the foreseeable future. They will wreak incredible damage across the planet, destroying land, buildings, causing death and misery and forcing entire communities to become refugees. All this regardless of any measures taken in Poland. 

And rising sea levels is only one of the consequences of global warming. In this context it is a shame and a disgrace that some choose not just to deny human involvement in climate change in defiance of all respected science, but to question whether it is happening at all, in defiance of clear, visible evidence.

Northern Ireland remains especially remarkable in the face of all this. Its land might be sinking more slowly than its neighbours. Yet it remains the only part of the UK without a Climate Change Act.