We know it well. It’s right outside our door, threaded into our daily lives — so, when things change in the Atlantic Ocean, we pay attention.
For fisheries workers, it’s central to their livelihoods. The condition of the ocean — temperatures, salinity, turbidity and currents — can cause booms and busts in fish species the industry depends on.
For the rest of us, it’s equally part of daily life — and not, as those foolish ads for saltwater nasal sprays seem to claim, because the sea air means no one who lives near the ocean ever gets a stuffy nose.
The ocean is our great moderator; a huge and stable temperature sink, it cools our summers and warms our winters, generates our fog and builds our winds. Whole weather patterns change as they cruise across open water, snow changing to rain, sun changing to grey — and with the right landward breeze, temperatures dropping by five degrees or more in the equivalent of a few minutes’ walk.
While we’re used to the ocean taking pretty much anything we dish out — from municipal pollutants to overfishing, to climate pollution causing rising ocean temperatures and increased acidity — it’s worth keeping a weather eye on our watery neighbour.
This past week, scientists talked about the increase that’s been showing up in ocean temperatures off Nova Scotia — it’s not a record high temperature, but, for the last decade, temperatures on the Scotian Shelf have been rising, and in 2015 (the last year for which full data has been collected) stood at three degrees above the 30-year average. (Three degrees doesn’t sound like much, but bear in mind the sheer volume of water involved and the massive amount of energy it would take to increase that volume of salt water by that many degrees.)
In October, 32 kilometres off the coast of the province, the water temperature on the bottom was 11 degrees, far higher than in past years. The suggestion now? That a warming Gulf Stream is pushing further north, changing its direction and deflecting the southern-running Labrador current, now carrying fresher water as Arctic ice melts, somewhere around the tail of the Grand Banks.
In some ways, research from Newfoundland and Labrador echoes that conclusion, though its ocean temperatures in 2015 were closer to normal than in the Scotian Shelf.
Lots of numbers, but what does it all mean?
Scientists looking at the Nova Scotia numbers caution that ocean temperatures are often cyclical — but when we’re the mice onshore, looking out at the neigbouring elephant of the Atlantic, you have to be paying attention.
New research in the journal Science Advances suggests continued and more severe change in Atlantic currents could be coming with increased levels of carbon dioxide in the atmosphere. We’d better watch carefully — because we’re on the cost, and on the front line.