2050: a perfect storm

The first warning came on the morning of Friday the 4th, when Met Éireann told people living on the west coast to batten down the hatches and avoid unnecessary travel.

By 4pm, electricity lines had been downed in Donegal. At 5pm, flights had been diverted from Kerry Airport. When 7pm arrived, homes in some counties were without power.

And as midnight approached, authorities' worst fears became real as gusts of almost 120kmh hit the country. Roads in Galway and Kerry flooded as rivers, swollen from weeks of rain, burst their banks.

But this was only a portent of things to come. A full month's rainfall fell in just 36 hours as the country descended into chaos.

This is not an apocalyptic vision of a future ravaged by climate change. These events struck the nation in December 2015 when Storm Desmond hit, one of many intense storms we have experienced over recent years as the world warms.

It enacted a terrible toll. A sea surge swept a woman and three teenagers into the ocean off Hook Head. Close to 50 pensioners were forced to shelter in a Mayo sports club after the River Moy burst its banks, swamping their nursing home. An elderly man was found dead in Monaghan, swept away by flood waters while trying to exit his marooned car.

And hundreds of homes and towns in Galway, Mayo, Cork, Kerry, Sligo, Donegal and Clare were flooded. Water levels on the River Shannon reached near-record highs. In Sligo, floodwaters rose to four metres, as raw sewage flowed through streets. Railway lines were closed in Cork and Wexford, and hundreds of roads shut.

The carnage continued for weeks, right into Christmas. Damages were in excess of €100m.

But as we approach 2050, when global emissions are supposed to be effectively zero, will these events be commonplace? And just how much at risk are we, and the services and infrastructure we rely on?

There is a direct link with extreme weather events and carbon emissions generated from human activity. By not cutting emissions, we are heightening the risk, scientists insist.

"While Storm Desmond was considered a one-in-100 year event, a near-real time attribution analysis found that such extreme rainfall was up to 40pc more likely due to the effects of human-induced climate change… making similar events now a one-in-72 year event," a report on adapting to climate change from the Department of Transport says.

Some of the stormiest winters on record have been over the last decade. Extreme weather events this year alone include Storm Eleanor in January, the sub-zero Storm Emma in March and the summer drought which led to water restrictions being imposed.

And the warnings from the UN's Intergovernmental Panel on Climate Change (IPCC) are clear. Last week it said time is running out, and we must dramatically cut emissions by 2030 to have any hope of limiting warming to 1.5°C and avoid catastrophe.

Time running out

Average global temperatures are already 1°C above pre-industrial levels, and are likely to reach 1.5°C between 2030 and 2052, if we continue with business as usual.

By 2100, we're looking at 3°C.

Research from the Irish Centre for High-End Computing at NUIG makes for grim reading.

Unless the world cuts emissions, average temperatures will be 1°C to 1.6°C warmer in Ireland by 2050, with highest averages in the east.

The growing season will be some 35 days longer, and the top 5pc of warmest days will be up to 2.6°C hotter than those recorded between 1981 and 2000.

There will be less spring and summer rain, with summer rainfall falling by as much as 20pc. The number of dry periods, defined as five days or more with less than 1mm of rain, could increase by as much as 40pc.

But there will be more heavy rainfall events in the autumn and winter, increasing the likelihood of flooding. Storms are likely to be more extreme. Other projections highlight how sea-level rise is likely to range from 50cm to 90cm by 2100, putting thousands of people at risk of coastal flooding.

These will not be benign changes. And even if countries ramp-up ambition and massively reduce emissions, we will still lose.

By way of example: coral reefs are home to around 25pc of all marine species. Holding average global temperature rises to 1.5°C will result in about 70pc being lost. Under a 2°C rise, it rises to 99pc. Taking action doesn't mean that humanity wins. It just loses less.

So how vulnerable are we, and what does an Ireland of 2050 where climate change has taken hold look like?

"We are going to see more storms, and you can see how vulnerable our agriculture system is to extremes, as well as our infrastructure including roads," Environmental Protection Agency (EPA) chief climate scientist Frank McGovern says.

Annual food and drink exports are worth €12.6bn, a 60pc rise since 2010, and potential damages of up to €2bn a year are forecast for the agriculture sector.

Fungal disease

While there will be fewer cold days and the growing season will extend, there is concern about vector-borne animal diseases, spread by mosquitoes, midges, ticks and other organisms which will arrive as temperatures increase.

Lumpy Skin Disease, which affects cattle and has been spreading rapidly globally, the Bluetongue virus and the Schmallenberg virus could come to our shores. Wet and warmer weather increases the risk of fungal diseases, and even the practice of farming will be more difficult.

Moving heavy machinery around in wet periods will pose issues. Harvests face delays, and crops will be damaged. Farm sheds will be damaged during extreme events.

Summer droughts will increase heat stress for animals and heighten the risk of forest fires. Water shortages will be more common.

In fact, water will be an enormous problem.

The first risk relates to the drinking water and wastewater system, and this year's drought highlights its vulnerability, Irish Water corporate affairs manager Kate Gannon says. On an upside, the utility now has accurate information about how the network performs when water is in short supply.

"Instead of us trying to model what a drought year would look like, we saw a drought year," she says. "We have 900 water treatment plants. We had over 30 water supply zones under restrictions and 100 at risk (this summer). We have a huge amount of data.

"The smaller, shallower sources failed first. The rivers were impacted first, then groundwater. There are isolated pockets (today) which are slower to recover. We are hoping for a good wet winter to build up resources."

She said reduced summer rainfall would result in lower river levels, with reduced capacity to supply treated water despite increased demand. This could lead to restrictions on a more frequent basis.

Increases in water temperature also affect how it is treated. New, resilient drinking water sources will have to be identified.

Conversely, extreme weather events will damage plants and other assets, putting them at risk of failure unless they are protected. Higher rainfall levels will also increase the risk of sewers flooding, leading to localised pollution.

The second water-related vulnerability is flooding, which poses a risk of death and injury but also causes damage to essential infrastructure and property.

Some two million people live within 5km of the sea, which is expected to rise between 50cm and a metre by 2100. While predictions of Irish cities being under water are far of the mark, given the investment in urban flood defences completed or planned, the Office of Public Works says more than 30,000 properties are at risk.

Projections suggest that by 2050, direct damages from flooding will amount to €1.15bn a year if appropriate defences aren't put in place. The Government has allocated €1bn over the next decade, but more money will be needed.

And defences may not be enough - we may have to abandon some parts of the country.

"There's a policy of planned retreat which exists in the UK for areas which simply are not economic to defend and which should be left to recover under water," Professor John Sweeney from Maynooth University says. "It mainly applies to areas which do not have high urban values, so outside the big cities and including farmland and golf courses.

"There are lots of areas in Wexford where councillors have agitated for coastal defences for agricultural land, but it simply doesn't make sense. Coastal defences can cost the equivalent per mile as a motorway. The thought of letting land go is anathema for many but I don't think we have really grasped the principle of planned retreat here."

Other areas of concern include parts of the Shannon Estuary, as well as Doonbeg in Clare, home to US President Donald Trump's golf course and hotel complex.

Defending access to these and other rural areas will also pose a challenge, and hard choices will have to be made.

We have 100,000km of road, but much is at risk of flooding, ice damage and disintegration. It is expensive to maintain, and repair, with rainfall in October and November 2009 - followed by a spell of sub-zero temperatures - causing damages totalling €225m.

During Storm Desmond, Cavan County Council alone was forced to close 50 roads, some of which were under one metre of water. And damage cannot be ignored, as it heightens safety risks.

"There's a deep underlying concern that we have a historic network with some roads built without any modern engineering standard," Sean O Neill from Transport Infrastructure Ireland says.

"Some, including national secondaries (connecting towns and villages), are vulnerable. In fact, much of the historic network is essentially sub-standard, it's roads built on top of roads which are built on top of tracks."

Older roads will need drainage installed, but doing this for large parts of the network will be fiendishly expensive. Will some have to be abandoned, impacting on private motorists and bus services, too? Will some areas become inaccessible unless on foot?

And there's also more than 25,000 road and rail bridges which run over water, at risk of scour damage where water eats away at the foundations. In 2009, the Malahide viaduct carrying northern line train services collapsed into the sea, and the risk heightens when piers are subject to fast-moving waters, likely to happen during flooding events.

Railways at risk

But other lines are also vulnerable.

The sea cliff supporting the railway near Ballygerry at Rosslare Harbour is being eroded at a rate of two metres per year. Based on current projections, the rail corridor could be undermined by 2030. This would mean no train service between Dublin and Rosslare Harbour, which given its links with France, will be a crucial port post-Brexit.

"Ultimately, you've also got vulnerable areas around Bray Head, Killoughter and the Murrough," Irish Rail spokesman Barry Kenny says. "We're looking at coastal defence works in the knowledge that to do nothing means the line cannot remain open in its current place. Based on trends, ultimately the Dublin to Rosslare line is at risk."

Dublin's Dart service is also vulnerable, with flooding at Salthill and Blackrock closing the line for a day earlier this year, affecting 80,000 commuters. And that's not the end of the railway company's woes. A section of the Galway to Limerick line at Ballycar has been flooded 17 times since 1930. Five flooding events have been in the last decade, despite the line being raised.

It was closed from December 2015 to May 2016. Flood-relief works are needed, but is there a point when transport bosses say the current alignment is not sustainable, and it must be moved? And if it must be moved, what will it cost, and who pays?

And as the world moves to an electric future, additional challenges crop up.

"When you have a good storm, you have people out of power for days," the EPA's Frank McGovern says. "If we're going to electrify our systems and generate from renewables, as we need to do, you're not going to bring people along if they have no light, or heat, or transport for a day or more. You need an unprecedented level of planning to do this."

Chief executive of national grid operator EirGrid, Mark Foley, says wind turbines automatically power down during extreme wind events, so power supply should be protected in the short-term. He says most power outages are caused by falling trees, so mounting lines on more robust infrastructure and creating 'sterile' corridors where no trees are present can prevent damage.

While putting power lines underground isn't a solution, he adds that in a low-carbon world, homeowners are likely to be more self-sufficient in relation to their power supply.

"In a future world where your home is heated with electricity, and your car is electric, you're likely to have more self-sufficiency like a solar panel or battery technology which one could argue would have you in a better place than when you are today," he says.

It's not all doom and gloom. There's always beer. But that too, will be impacted.

Global warming is likely to lead to sharp falls in barley yields, an essential ingredient of the world's favourite beverage.

Scientists predict droughts and heatwaves will cause declines of up to 17pc in crop yields where the grain is grown, which could increase the price of a six-pack of beer by an extra €17.

That alone is reason to take climate action now.

Global warming in numbers

1.5°C   

Average global temperature rise above pre-industrial levels predicted by 2030, an increase of 0.5°C from today.

3°C   

rise by 2100, based on current levels of emissions.

1  

ice-free Arctic summer per century if rises kept to 1.5°C. This increases to once a decade with 2°C of warming.

99pc

Percentage of coral reefs which will be lost under 2°C rise.

20pc   

Drop in percentage of days with rainfall over the summer in Ireland, if emissions remain high.

87cm   

increase in global sea level rise by 2100 if temperatures increase by 2°C. Rises of up to one metre expected in Ireland.

2m  

Irish population living within 5km of the sea, which could be hit by sea-level rise.

500km

Irish coast at risk of erosion.

€1.15bn

cost of damage caused per year by flooding by 2050.

135m

rate of erosion at Rosslare sea cliff between 1905 and 1999.