John Paul Tieran
The Atlantic Ocean’s greatest contribution to this county and country is not the amount of fish it provides, or shellfish it sustains, or even the amount of tourism it generates, but the rather simple way in which its relatively warm water heats the air over it and a constant supply of low-pressure systems push that air towards us, keeping our winters mild, moist and trouble-free.
If something disrupts that key relationship between us and the ocean, the result is ice, snow and everything that has happened in the past month. For the second year in a row, the North Atlantic effectively shut down as a huge high pressure system set up just below Greenland, preventing low pressure systems from developing and coming towards us and allowing cold north-easterly air to flow down from Scandinavia.
With so much said for global warming, why two cold winters in a row? Don’t go looking at it in the hopes of seeing them, but the reason may have something to do with the sun losing its spots. Sun spots are huge dark spots – 50,000-plus miles wide – on the sun’s surface.
Their level of activity somehow influences the activity of the North Atlantic, and when they reached very low levels of activity in the past (1600s, 1700s), Europe experienced mini ice-ages.
Sunspot activity has been exceptionally low in the last two years and if this theory, which is one of many, is somehow accurate and is the reason for a quiet Atlantic and a freezing Ireland, it means the next four to ten winters might continue in a similar mode.
So what would an inactive Atlantic mean for our marine life? Unfortunately that was a question which nobody could give time or money to answering in the recent past. Before last year, our winters had been warming since the 1950s, and all studies had been directed toward predicting what will happen as they keep warming.
Studies relevant to Mayo predicted that the impacts of a rise in temperatures would include such declining stocks of salmon and sea trout (backed up by data from Burrishoole), the appearance of new warmer-water species and decreases in seabird populations.
Were the opposite now to occur, one cannot expect these things to be simply reversed; science and nature doesn’t work like that.
Will 2011 confirm a new trend of cooling winters and give scientists a whole new question to tackle? Or will normal winter-time relations with the Atlantic Ocean resume? We’ll need at least one more year before we can really be sure.
John Paul Tiernan, Louisburgh, runs www.irishmarinelife.com, a website dedicated to the creation of knowledge of our marine ecosystems. He is currently studying for an MSc in Marine Science.