Thar She Blows
2.2.08
Donald Burfitt-Dons

Captain Ahab’s memorable line from Melville’s Moby Dick could well have been spoken by a latter day ship’s captain as his ship homed in on the west coast of England. Captain Smith, presumably under pressure from his operating company, had decided that conditions were suitable to set out from the Northern Ireland port of Warrenport for Heysham in Lancashire.

Like the ill-fated Pequod in Melville’s novel, the Riverdance was also doomed. As the seas mounted, driven by a North Atlantic depression with a core pressure of 957mbs centred west of Scotland, the high sided vessel began to list. Approaching Blackpool in darkness an initial Mayday was sent out, and, in horrific conditions the passengers were air lifted off. The crew remained on board until, with the ship listing to 60 degrees a further Mayday was issued and the crew too abandoned the ship.

Kevin Hobbs,CEO of Seatruck Ferries glibly explained on the BBC that conditions were no worse than normal on the Irish Sea. “We were just unlucky” he added. I very much doubt the captain saw it that way on the bridge in the middle of the night, struggling with insufficient rudder for control because of a huge following sea driven by the 60 knot winds.

What has not yet been appreciated by the maritime industry is that the oceans are facing a new set of meteorological conditions which lie outside the present design parameters. High sided vessels, such as modern ferries are particularly vulnerable to cross winds and following winds. On January 15th January another ferry was lost in the English channel off Poole. The Ice Prince was caught in south westerly gale force winds running at right angles to the vessel, causing extreme rolling. The cargo shifted and that was that. The ship rolled over and was lost.

As the oceans around our land masses warm, the released energy is resulting in ever deeper depressions. We warned of this effect in a GWA article “Life on the Ocean Wave.” And, consistent with our research, such conditions are going to occur ever more frequently in the future. As we have written elsewhere, because the force exerted on a body is a function not just of air density (a more or less constant), which is then multiplied by the velocity squared. It is this which increases the force so dramatically as wind speed increases.

Deep depressions are of course common in the North Atlantic in winter. This particular one was further south than normal crossing directly over Scotland instead of to the North.

If the ever deepening lows begin to migrate southwards we can expect further mayhem to our shipping. In our article in 2006 we said that eventually the seas may become unnavigable and we have no reason to change that view. North Atlantic lows should be viewed with extreme caution by ships operating in the high latitudes, especially if their centres are located further south than normal. Just like hurricanes, warmer seas give a system greater energy, and hence even stronger winds.

The climate models are still underestimating the rate of change to our global weather systems driven by global warming, thus Governments do not fully appreciate how little time remains for action.