In the wake of Ophelia and Brian, there are another 15 storms set to hit land in Ireland this autumn. Caroline, Dylan, Eleanor, Fionn, Georgina, Hector, Iona, James, Karen, Larry and Maeve are all expected to arrive on our shores in the coming months. This is twice as many as last year. Hurricane Ophelia brought tropical heat from the Azores and this residual heat combines with polar air and 170mph jet stream winds over the Atlantic Ocean to create enough turbulence for ocean storms to push their way onto land. Atlantic storms are created by the difference in air temperature and during autumn the cold polar air and warm tropical air have the greatest difference meaning stronger storms.
Atlantic storms usually move westward toward the Caribbean Islands or the United States. They eventually lose most of their energy and either make landfall or regress back out onto sea as minor storms. Hurricane Ophelia was unusual as it went eastward toward the Azores and track up toward Ireland and Great Britain. Since records began in 1851, there have only been 15 hurricanes that have passed within 200 nautical miles of the Azores. So why has this occurred and should we be worried?
A study published in 2013, provided evidence that global warming is making the area in which a tropical storm can develop much larger, and particularly more eastward, which is not the usual direction. Combined with recorded higher sea surface temperatures, this means that tropical storms are much more likely to arrive at regions of the tropics, i.e. the Azores, adding fuel to the fire. The tropics lie in a midlatitude baroclinic region, for those non-meteorologists out there this is a region where the difference in air temperature and air pressure can yield enough density to basically give an Atlantic storm a second wind. Like giving a student in JJ two shots of espresso at 9pm, the storm will reintensify potentially with enough force to make it reach Western Europe. This is common of hurricanes that hit many of the Caribbean Islands and North America. The fact that this is happening now and the reasons that it happening, global warming and rising sea temperatures, means that it will more than likely continue to happen. Western Europe will be hit with many more tropical storms and there is a chance they will only continue to intensify and grow into hurricanes.
Climate is the average weather of a region measured over 30 years. These predictions have been based of data that has been collected on two samples of 30 years. Ireland currently has a mild, moist, temperate climate. We do not have any extreme weather conditions and do not usually have to worry about the loss of life from the weather. Although we are in the Northern Atlantic, our winters remain relatively mild as we get a stream of warm water starting in the Gulf of Mexico, called the Gulf Stream. Global warming will bring about melting of the polar ice caps. This will in turn release large volumes of cold Arctic water that will push the Gulf Stream to a lower latitude, meaning that we will presumably be set for extremely cold winters with much of our west coast being frozen through out the winter, how very Jake Gyllenhaal in The Day After Tomorrow. Climate change is happening, Ireland’s weather will become more tempestuous, and the best we can do is prepare ourselves for it.
Orla Daly – Science Editor