This week’s extreme flooding in the northwest, concentrated on Co Donegal, underlines the urgent need to have adequate “adaptation measures” in place as such weather incidents are going to increase in frequency.
That is the verdict of Irish climate change experts, who have no doubt that global warming increased the ferocity of Tuesday's thunder storms.
While there were particular meteorological circumstances that led to the floods, Prof Peter Thorne, who is the director of the Irish climate analysis and research units at Maynooth University, said climate change "undoubtedly increased the magnitude of the event".
As human activity continues to contribute to global warming (by way of carbon emissions), it has “weighted the dice more” so it was “pretty certain that more frequent intense rainfall” would affect Ireland.
The inevitability of “more to come”, he said, related to increased global temperatures. For every degree the globe warmed, the atmosphere can hold 7 per cent more water vapour. The consequence was more rainfall.
He said it was also unlikely that the increase could be confined to 1.5 degrees this century. Even if the world became “carbon neutral” oceans would continue to warm.
As a consequence, in preparedness for climate change, mitigation and adaptation assumed critical importance. That required “getting off the carbon highway”, and taking the right decisions on infrastructure, and insurance, Prof Thorne said.
Raising bridges
It required “climate-smart infrastructure fit for 50 to 100 years’ time”, he said. That could mean bringing flood defence walls up by a metre, reinforcing or raising bridges, and moving road locations to somewhere they were less likely to get flooded.
Landslides in Donegal were not just a consequence of climate change, he said. Land use and environmental practice had to come into play as these factors “could mitigate or make worse a climate event”. Consideration of better “soft infrastructure” such as woodlands and breaks in farmland were also necessary.
On insurance issues, he said with increased frequency of extreme weather came greater issues for society to contend with. “It gets extremely difficult and contentious very quickly.”
TCD professor of geography Peter Coxon highlighted differences between previous widespread flooding in the Shannon region and that which hit Donegal.
The recent deluge hit mountains and hilly areas with impermeable rocks overlain by peat and wet soils, which meant "the landscape was going to react". It was "not as simple as not building on floodplains". There needed to be greater research on areas vulnerable to floods and landslides, he told RTÉ's Morning Ireland.
There were particular difficulties with older infrastructure which was not engineered to accommodate for rare extreme weather events. He agreed that €430 million set aside for flood defences between now and 2021 was not enough. Local authorities needed to be able to advise on methods to protect property and lives from such events.
National adaptation plan
The Government is required to publish a “national adaptation plan” to set out specifically what measures it will take to address climate change impacts, notably relating to infrastructure, planning and flood relief.
Minster for Climate Action and the Environment Denis Naughten has acknowledged that it will require funding to address likely damage – the plan is due to be published in coming months. Since last year local authorities are required to have their own mitigation plans.
EPA director general Laura Burke warned last year of the critical role of local authorities in reducing vulnerabilities.
“Simply cleaning up after flood and storm events is no longer enough. We must now plan to adapt our economy, society and environment to deal with the reality of climate change, and to manage the risks it poses to our way of life, livelihoods and wellbeing.”
