pH (depth-averaged) time series over the Scotian Shelf (1933–2014, declining trend of 0.026 per decade; 1995–2014, declining trend of 0.044 per decade); near-bottom estimate (approximately 300 m) of pH in the Gulf of St. Lawrence (1935–2007, declining trend of 0.021 per decade; 1990-2007, declining trend of 0.026 per decade); and pH from the central Labrador Sea in the annually ventilated layer (150–300 m) (1996–2016, declining trend of 0.029 per decade). Estimates of pH before the 1990s have a high level of uncertainty because of the quality of the measurements and should be interpreted with caution. Therefore, no assessment of statistical confidence is provided for the observed trends.
