As if the Arctic didn’t have enough to worry about. In addition to diminishing sea ice, pollution and rising temperatures, scientists are now warning of the widespread effects that ocean acidification could have on the North.
When carbon-rich materials (such as coal or oil) burn, carbon dioxide floats up into the atmosphere. But not all of the gas goes up; the oceans absorb some of it. While this slows the buildup in the atmosphere, it also increases seawater acidity. That spells possible trouble for Arctic marine organisms and for the people who depend on them, according to the newly released Arctic Ocean Acidification Assessment.
“As a result of human carbon dioxide emissions, the average acidity of surface ocean waters worldwide is now about 30 per cent higher than at the start of the Industrial Revolution,” the report states.
The issue was only one of the topics on the agenda at this week’s Arctic Council meeting in Kiruna, Sweden. This year, Canada takes the helm of the multinational forum.
Notable chemical effects related to acidification have been detected in the Canada Basin of the central Arctic Ocean and the Bering Strait, among other places.
The Arctic Ocean is particularly susceptible to acidification. One reason is that the ocean is rather cold. This makes it easier for the carbon dioxide in the air to transfer into the water. Also, particularly in areas where rivers and melting ice are diluting the ocean with freshwater, it becomes harder to neutralize the carbon dioxide’s acidifying effects. And the scientists predict it’s going to get worse - as summer sea ice decreases, more ocean is left uncovered and vulnerable.
More research needs to be done into how higher acidity will affect marine life. The best-studied direct effects include effects on shell formation and organism growth, reports the assessment. Some seagrasses, on the other hand, appear to thrive under such conditions. Birds and mammals are not likely to be directly affected, but they could feel the hit if their food sources change as a result of acidification.
The report recognizes the complex nature of the changes happening in the Arctic. Even under the auspices of acidification there are a variety of contributing factors: coastal erosion, freshwater inputs, and plant growth/decay can all exacerbate acidification.
“The contributions of these processes vary not only from place to place, but also season to season, and year to year. The result is a complex, unevenly distributed, ever-changing mosaic of Arctic acidification states.”
The report was released by the Arctic Monitoring and Assessment Programme, one of the Arctic Council's working groups.