aariПроблемы Арктики и АнтарктикиArctic and Antarctic Research0555-26482618-6713Государственный научный центр Российской Федерации Арктический и антарктический научно-исследовательский институт10.30758/0555-2648-2021-67-3-230-235aari-386Research ArticleОКЕАНОЛОГИЯOCEANOLOGYThe effect of using local mean versus constant reference salinity to estimate Arctic Ocean freshwater content changesThe effect of using local mean versus constant reference salinity to estimate Arctic Ocean freshwater content changesPolyakovI. V.PolyakovI. V.

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ivpolyakov@alaska.eduInternational Arctic Research Center, University of Alaska FairbanksСоединённые Штаты АмерикиInternational Arctic Research Center, University of Alaska FairbanksUnited States202106102021673230235Copyright © Polyakov I.V., 20212021Polyakov I.V.Polyakov I.V.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.aaresearch.science/jour/article/view/386

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 Sref divided by this Sref . A constant Sref is often used for high-latitude FWC estimates. Here it is argued that for analyzing FWC spatiotemporal changes the use of local mean Sref is a better choice. Analysis of 2007 FWC anomalies in the 25–75 m layer demonstrated, for example, that the choice of Sref = 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 Sref and Sref = 34.8 is greater. Thus, it is concluded that using climatological mean salinities as Sref provides superior estimates of spatiotemporal Arctic Ocean FWC changes.

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 Sref divided by this Sref . A constant Sref is often used for high-latitude FWC estimates. Here it is argued that for analyzing FWC spatiotemporal changes the use of local mean Sref is a better choice. Analysis of 2007 FWC anomalies in the 25–75 m layer demonstrated, for example, that the choice of Sref = 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 Sref and Sref = 34.8 is greater. Thus, it is concluded that using climatological mean salinities as Sref provides superior estimates of spatiotemporal Arctic Ocean FWC changes.

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The authors declare that there are no conflicts of interest present.