A team of US scientists analysed data from three years of research cruises in the Arctic Ocean. The results indicated that the recent extreme melting of sea ice in the Arctic has led to higher than expected levels of acidification. As the sea ice melts, the underlying seawater becomes exposed to carbon dioxide, which dissolves in the water to form carbonic acid. To make matters worse, the increase in fresh water caused by the sea ice melting dilutes the sea water, lowering pH levels and reducing the concentrations of calcium and carbonate, which many marine micro-organisms use to form their skeletons and shells.
‘A remarkable 20 per cent of the Canadian Basin has become more corrosive to carbonate minerals in an unprecedented short period of time. Nowhere on Earth have we documented such large-scale, rapid ocean acidification,’ said the study’s lead author, Lisa Robbins of the US Geological Survey.
‘In the Arctic, where multi-year sea ice has been receding, we see that the dilution of seawater with melted sea ice adds fuel to the fire of ocean acidification,’ said one of the study’s co-authors, Jonathan Wynn of the University of South Florida.
This story was published in the November 2013 edition of Geographical Magazine