Open AccessThe effect of using local mean versus constant reference salinity to estimate Arctic Ocean freshwater content changes
Author(s) -
Igor V. Polyakov
Publication year - 2021
Publication title -
problemy arktiki i antarktiki
Language(s) - English
Resource type - Journals
eISSN - 2618-6713
pISSN - 0555-2648
DOI - 10.30758/0555-2648-2021-67-3-230-235
Subject(s) - salinity , latitude , arctic , environmental science , the arctic , polar , atmospheric sciences , oceanography , geography , physics , geology , geodesy , astronomy
Changes of high-latitude freshwater content (FWC) play an important role in shaping the variability of polar oceans. FWC is defined as depth-integrated departure of salinity from a reference salinity S ref divided by this S ref . A constant S ref is often used for high-latitude FWC estimates. Here it is argued that for analyzing FWC spatiotemporal changes the use of local mean S ref is a better choice. Analysis of 2007 FWC anomalies in the 25–75 m layer demonstrated, for example, that the choice of S ref = 34.8 (which is often used in climate studies) leads to FWC spatial anomalies exaggerated, on average, by ~0.6 m, which is a substantial fraction of total spatial FWC changes. The problem is aggravated in areas where the difference between the local S ref and S ref = 34.8 is greater. Thus, it is concluded that using climatological mean salinities as S ref provides superior estimates of spatiotemporal Arctic Ocean FWC changes.