IF smaller boats or swimmers had been caught up in the freak tides and raging waters that hit the West Cork coast on Saturday afternoon, they would have been swept away in seconds, observers have said.
Union Hall and Courtmacsherry saw the most dramatic activity, with the tide travelling in the wrong direction for a time from around 3.40pm.
In just five minutes, Union Hall harbour was drained, and water levels dropped by 70cm, compared to the normal rate of around 1cm per minute. Boats were grounded, moorings were exposed, and small fish were left washed up on the shore. Freakish tidal activity was also seen in Castletownbere, Bantry, Kinsale, Timoleague, and even as far away as Wexford, Cornwall and Pembrokeshire in Wales.
Michael Walsh from Rosscarbery was making his way back into Union Hall harbour on Saturday afternoon around 4pm when his boat suddenly ran aground in sand.
‘We floated again in a few minutes, but this has never happened to me before and I’ve been going in and out of the harbour for years,’ he said. When he got back to his mooring a ‘flood of water’ went by the boat. ‘It was like a raging river. If you were swimming you’d have been swept away in a second,’ he said. ‘We got into the smaller boat to row to shore but it was almost impossible with the current – we were almost moving backwards,’ he said.
‘It was frightening to think of a swimmer being caught up in it. They’d have been in serious trouble.’
Adrian Nowotynski from Drinagh saw the tide going in and out at Union Hall five times between around 3.30 and 5pm. Like Michael, he was on his boat when the first tide hit, and he was also stuck in mud for a few minutes, before making it to shore.
‘But if I had been in my dinghy, even two minutes earlier, I’d have ended up in Glandore.
‘Speeds went from six knots an hour to at least 10 or 12. The suddenness of it was a bit scary.’
Anne Kelleher was driving over Union Hall bridge at 5.50pm: ‘I was in the middle of the bridge and looked to the south side of it and noticed a torrent of water flooding through. I thought it was a couple of speed boats that had gone under the bridge and this wash had been created by their movement. But, looking to the northern side, I could see there weren’t any boats in sight and a moored boat further up on that side had a torrent of water rushing against it. I have been driving across the bridge for many years and have never seen this before.’
Dr Gerard McCarthy, an oceanographer with the Irish Climate Research and Analysis Unit (Icarus) in the Department of Geography at Maynooth University said the most likely cause was a ‘meta tsunami’.
The Clonakilty native linked it to a sudden squall that blew up earlier off the coast of Normandy. ‘Winds went from zero knots per hour to 100 knots per hour in five minutes and tragically a wind surfer was killed,’ he said.
This meterological event, he felt, coincided with the natural seiching (water moving backwards and forwards) in Union Hall and Courtmacsherry harbours which resulted in the dramatic scenes witnessed on Saturday.
‘Normal weather warnings do not pick these up and without a doubt, swimmers or anyone in a small boat would have been in danger if they were caught up in it,’ he said.
He said experts are a long way from fully understanding meta tsunami, and on a smaller scale, they’re not uncommon on our coast.
‘I don’t think there’s any need to be any more afraid of the ocean than you would have been before,’ he concluded.
The Marine Institute is investigating the incident and will collaborate to determine what happened.