Hurricane Ophelia: the shape of things to come?

Climate change is undeniable and Ireland must tackle greenhouse gas emission

Some 120,000 homes are without power on Monday as Hurricane Ophelia sweeps in over Ireland with damaging gusts and heavy rainfall.

Situated at the receiving end of the Atlantic storm tracks, Ireland has a long history of coping with extreme storms. Wind has always been the most feared weather element in Ireland. Indeed the Annals of the Four Masters contain what is probably the earliest surviving written record of a weather event in Europe, a storm on Lough Conn in Co Mayo, in 2668 BC. While we can take the actual date with a pinch of salt, it is indicative of the imprint storms have made on the Irish psyche. We remember these events as benchmarks to compare our contemporary experiences with.

So, for example when old-age pensions were introduced in Ireland in 1909 for people over 70, potential recipients without birth records were asked could they remember the night of the Big Wind of 1839. If they could, they qualified. And well they might remember this event, probably the most severe storm to affect Ireland over the past few centuries, with bizarre reports of herring being blown several miles inland, 42 shipwrecks and thatched cottages being destroyed by wind and fire on a large scale.

We remember "Hurricane" Debbie in September 1961 when the wind record for Ireland was established at Malin Head with a gust over 180km/h, and more recently Storm Darwin in February 2014 when a gust of 160km/h was recorded at Shannon Airport and the Kinsale gas platform was hit by a 25m wave.

Over the past four years Ireland has experienced the wettest winter on record over most of the country, the stormiest winter of the past 147 years, and now its first taste of a near-intact Atlantic hurricane

The autumn storm season in Ireland is often enhanced by the remnants of hurricanes coming across the Atlantic, having transformed themselves into deep mid-latitude depressions as they encountered the colder waters of the north Atlantic. Sometimes this occurs before they make their transatlantic journey; but the eye and the tropical characteristics associated with a true hurricane are always replaced with characteristics more typical of a mid-latitude frontal depression. That is not to say they are any more benign.

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Different beast

So what are we to make of Hurricane Ophelia? Certainly it is an entirely different beast from our usual storms. Forming in the Azores, it was caught up in a deep trough in the upper air westerlies and instead of heading west was pushed almost due north, reaching category 3 early in its journey. Because of this short track, it was slow to lose its tropical characteristics and only became entitled to call itself an extra tropical cyclone a few hours before it approached the Irish coast. On Monday, much of the country went into lockdown with schools, colleges and many businesses and transport systems closing down, and coastal residents being urged to take special precautions. By midday, gusts over 130km/h had been recorded on the south coast and the first fatality had occurred.

Over the past four years Ireland has experienced the wettest winter on record over most of the country, the stormiest winter of the past 147 years, and now its first taste of a near-intact Atlantic hurricane. For most Irish people, the question has been: is this the shape of things to come? Interestingly, all these aforementioned extremes may have a common denominator: the warming of the Atlantic Ocean. Where Ophelia formed as the 10th straight hurricane to develop from a tropical storm, the surface water temperatures were 2 degrees above normal, and crucially above the 26-degree threshold temperature where hurricane development is possible. Without this extra warmth, Ophelia probably would not have developed so readily.

Ireland is not known for meeting its obligations on greenhouse gas emission reductions

Destructive potential

How Atlantic hurricane frequency and intensities will respond to greenhouse gas-induced global warming is a topic where the jury is still out. The latest report of the Intergovernmental Panel on Climate Change suggests that while the numbers may not change too much, the intensity and destructive potential will likely increase as global warming proceeds. In terms of culpability for this, Ireland is not known for meeting its obligations on greenhouse gas emission reductions. Last week in Luxembourg, as the rules for 2030 emissions reductions were being set, it sheltered behind intransigent countries in eastern Europe, seeking maximum concessions and essentially passing the burden anywhere but home. This is not what the Citizen’s Assembly’s mandate of “How the State can make Ireland a leader in tackling climate change” is about.

Perhaps Ophelia will assist in sensitising the Irish public to the reality that things are likely to get worse in terms of extreme events, and that the combination of circumstances that produced Ophelia are on balance more likely to increase rather than decrease in the years ahead. Our children and grandchildren will assess how much we have contributed to their misfortune or not.

John Sweeney is professor emeritus in the department of geography at Maynooth university