Trans-Atlantic research aims to unlock climate change mysteries

Scientists from six countries have teamed up on a slow boat from Newfoundland to Ireland to take a hard look at the possible effects of climate change on the northwest Atlantic Ocean.

"It's going to take a month to get there because we stop every 30 miles and lower instruments down to the sea floor and collect water, bring it back up, and measure it," said Doug Wallace, a chemical oceanographer from Halifax's Dalhousie University who is leading a team of researchers on the Celtic Explorer.

"Understanding this part of the ocean is really key to understanding how climate change is happening and how it will happen in the future," he said.

"The Atlantic is one of the most important places where the ocean sucks carbon dioxide out of the atmosphere and delivers it into the deep ocean."

Carbon gases created by the burning of fossil fuels, such as oil, are commonly blamed for climate change because they help trap heat in the earth's atmosphere.

The Atlantic Ocean absorbs a huge amount of the world's carbon dioxide. It's what scientists call a "carbon sink," and it plays a crucial role in regulating the world's climate.

"It helps to limit the increase of carbon dioxide in the atmosphere and limits the amount of global warming that we would otherwise have," said Wallace. "Over the past 200 years, almost 50 per cent of the carbon dioxide emitted by humankind is now dissolved in the ocean somewhere.".

But he said the ocean's rate of carbon uptake is decreasing — a worry for Brad de Young, a Memorial University oceanographer who's also on the Celtic Explorer.

"Knowing how that process is changing is crucial to understanding what is going to happen in 10 years or 20 years as we keep putting carbon dioxide into the atmosphere. Where is it going to end up, and will that rate of draw down into the ocean increase or slow down?" he asked.

"All of which will have huge implications for the future climate."

Warming hole

One of the mysteries the researchers are trying to shed light on is: Why is climate change affecting Newfoundland differently from other parts of the world?

"It's a curious thing. If you look at a map of where temperature rises are happening in the atmosphere and on land, this region hasn't experienced as much warming as others," said Wallace.

"The Arctic, of course, has changed dramatically. Most of the rest of the planet has warmed significantly over the past 100 years but there is a little region here in the northwest Atlantic where temperatures haven't increased greatly. Some people call it the 'warming hole,' and the reason for that has to do with the behaviour of the ocean in this part of the world."

Newfoundland saw a lot of icebergs early this year. While Wallace said it's difficult to place a one-year event within a long-term pattern of climate change, he said there is more fresh water, including icebergs, moving south, and that could affect ocean currents.

"Typically waters between Labrador and Greenland sink but if the water becomes too fresh, that process can slow down or even, I suppose, stop. So, the icebergs might be just one hint of that."

Led by Marine Institute of Galway

The research is being led by the Marine Institute of Galway, Ireland — a partner in the Ocean Frontier Institute, co-founded by Memorial University of Newfoundland, the University of Prince Edward Island and Dalhousie University.

The institute was established in 2016 with $220 million from the federal government and various private and public sector organizations. The research voyage represents the first step in the OFI partnership to explore sustainable ecosystems in the Northwest Atlantic.

"There's more to come because this is really just the first substantial, real activity of this group and it covers a wide range of things like looking at the ocean like this ship will do, to modelling, to looking at fisheries issues, to aquaculture," said de Young.

"To build enough understanding to provide real benefits to the societies that depend on those ecosystems … which is all of us."

The Celtic Explorer left St. John's on April 27 with scientists from the U.K., Germany, Denmark, South Africa, the U.S. and Canada. It's expected to arrive in Galway on May 23.