Проблемы Арктики и Антарктики

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The effect of using local mean versus constant reference salinity to estimate Arctic Ocean freshwater content changes

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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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Об авторе

I. V. Polyakov
International Arctic Research Center, University of Alaska Fairbanks
Соединённые Штаты Америки

930 Koyukuk Drive, Fairbanks, AK, 99775

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Для цитирования:

Polyakov I.V. The effect of using local mean versus constant reference salinity to estimate Arctic Ocean freshwater content changes. Проблемы Арктики и Антарктики. 2021;67(3):230-235.

For citation:

Polyakov I.V. The effect of using local mean versus constant reference salinity to estimate Arctic Ocean freshwater content changes. Arctic and Antarctic Research. 2021;67(3):230-235.

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ISSN 0555-2648 (Print)
ISSN 2618-6713 (Online)