Could Ophelia Herald an Increase in the number of European Hurricanes?

If the news of a major hurricane tearing for the coast of Ireland seems odd, as was the case for Hurricane Ophelia, that’s because the phenomenon of hurricanes surviving as organized storms that far east in the Atlantic Ocean is extremely rare. As it is, Ophelia now holds the record for the easternmost major hurricane in the Atlantic, and if it had maintained its strength it would have been only the third known tropical storm to make landfall in Europe, following 2005’s Hurricane Vince, making landfall in Spain, and Hurricane Debbie, brushing the west coast of Ireland in 1961.

The 2017 Atlantic hurricane season has been especially active, with, as of mid-October, the highest number of hurricanes and the highest total accumulated cyclone energy (ACE) since 2005, and the greatest number of consecutive hurricanes in the satellite era. Hurricane Ophelia itself is the seventeenth tropical cyclone, fifteenth named storm, and the sixth major hurricane of the season; after briefly reaching category-3 status on Saturday, the storm made landfall in Ireland this morning as a post-tropical storm, with its powerful winds causing the death of three people.

But what allowed Ophelia to exist as such a powerful storm so far east? Above average sea-surface temperatures along the 40th parallel between Portugal and The Azores, combined with a light wind shear helped sustain the storm. Although it’s not uncommon for storm systems that originate as hurricanes to reach Europe — once every 3.5 years on average — the vast majority of them simply weaken into strong storms, as the northeast Atlantic is typically too cold to support the cyclonic structure of a tropical storm.

But as sea surface conditions in the North Atlantic continue to change as global warming progresses, this raises the question of whether or not more organized storms will make landfall in Europe in the future. A 2013 study, titled "More hurricanes to hit western Europe due to global warming", concluded that as ocean and atmospheric conditions change, the likelihood of cyclonic storms that are more characteristic of the US East Coast hitting Europe, could become more commonplace.

"We anticipate an increase in severe storms of predominantly tropical origin reaching western Europe as part of 21st century global warming," according to the study.