Around the freezing point, salinity is the dominant factor controlling seawater density. In coastal Arctic waters, salinity varies widely with the seasons. An uncorrected salinity change from 34 psu to 20 psu at 0°C would result in a depth error of about 0.1 m in 10 m of water. Therefore, correcting for salinity is recommended. Beneath sea ice, the water column is typically well mixed. Therefore, vertical stratification (less dense water near the surface) is unlikely to introduce significant error in the density calculation.
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