The chemical development of a hypersaline coastal basin in the High Arctic

Dugan, Hilary A.; Lamoureux, Scott F.

doi:10.4319/lo.2011.56.2.0495

Cited by 13 publications

(7 citation statements)

References 52 publications

(91 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The impact of salt exclusion during ice formation on circulation is well understood for oceans (Carmack ), and for aquatic systems with salinities comparable or higher than seawater (Gibson ; Dugan and Lamoureux ). In these saline systems (i.e.,

\overset{S}{true}

≳ 24 g L −1 ), the freezing temperature (

{\overset{false˜}{T}}_{f}

) is higher than the temperature of maximum density (

{\overset{false˜}{T}}_{md}

), so both surface heat loss and excluded salts will increase the water density beneath the ice.…”

mentioning

confidence: 99%

Under‐ice salinity transport in low‐salinity waterbodies

Olsthoorn

Bluteau

Lawrence

2019

Limnology & Oceanography

View full text Add to dashboard Cite

In cold and temperate climates, ice typically covers the surface of waterbodies during winter. Many of these systems are also weakly saline where, unlike seawater, the temperature of maximum density, Tfalse˜md, is higher than its freezing temperature, Tfalse˜f. This feature of the equation of state results in a stable temperature stratification when surface waters cool below Tfalse˜md. Conversely, salts excluded from the growing ice can destabilize the underlying water. Previous laboratory and field experiments demonstrated that excluded salts generate localized overturning and downward transport of salt, despite the persistence of a stable temperature gradient. Those experiments were not able to determine the processes responsible for this transport. Here, we use direct numerical simulations to visualize and characterize the plumes generated when ice excludes salt into a stable temperature gradient. We restrict our analysis to times much earlier than the diffusion timescale of temperature over the domain. We define a mass flux parameter ℜ that considers the strength of the reverse‐temperature stratification relative to the rate of salt exclusion. We identify two types of plumes whose characteristics depend mainly on ℜ: double‐diffusive salt‐fingering plumes and convective plumes. The former encourages transport of salt to the bottom without significantly mixing the temperature stratification, while the latter tends to mix the water column. We apply a scaled mass flux parameter to published laboratory and field observations in low‐salinity systems. These limited observations compare favorably with our numerical analysis.

show abstract

\overset{S}{true}

≳ 24 g L −1 ), the freezing temperature (

{\overset{false˜}{T}}_{f}

) is higher than the temperature of maximum density (

{\overset{false˜}{T}}_{md}

), so both surface heat loss and excluded salts will increase the water density beneath the ice.…”

mentioning

confidence: 99%

Under‐ice salinity transport in low‐salinity waterbodies

Olsthoorn

Bluteau

Lawrence

2019

Limnology & Oceanography

View full text Add to dashboard Cite

show abstract

“…Meromixis is a natural stage of ecosystem development for relict lakes along sea shores (Hakala, 2004; Dugan & Lamoureux, 2011). Different layers separated by density barriers serve as biotopes for different communities of microorganisms.…”

Section: Discussionmentioning

confidence: 99%

Study of microbial communities in redox zone of meromictic lakes isolated from the White Sea using spectral and molecular methods

et al. 2015

View full text Add to dashboard Cite

Due to postglacial isostatic uplift many stratified lakes, at different stages of isolation, are located along the shores of the White Sea. In five lakes, located near the White Sea Biological Station of Moscow State University, salinity, temperature, pH, concentration of dissolved oxygen, redox potential, and illuminance were measured. Distribution of microorganisms and spectral properties of water layers were also studied. All the lakes had a narrow bright coloured layer in the redox zone caused by mass development of phototropic microorganisms. Light absorption and fluorescence spectra indicated algae containing chlorophyll a predominate in the red water layers while the colouration of green and brown layers is caused by green sulphur bacteria with bacteriochlorophylls d and e. Sunlight is completely absorbed in the redox zone because of the high density of algae and/or bacteria, resulting in aphotic conditions below. Coloured layers act as a specific biotope for special communities of microorganisms. Eukaryotes identified by the 18S rRNA gene included different species of mixotrophic algae and ciliates resistant to anoxia. The water layer colour and spectral characteristics (i.e. light absorption and fluorescence) of water in the redox zone can be considered indicators of the stage of lake isolation from the sea, with the red colour caused by cryptophyte alga Rhodomonas sp. bloom found in earlier stages and brown and green colours caused by green sulphur bacteria in later stages.

show abstract

“…For the Black Sea, enrichment in deuterium and 18 O isotopes for the deep waters (depth over 500 m) compared with the surface layer is explained by mixing of surface water with the Lower Bosporus Current inflow (Dubinin et al, 2014). For seasonally isolated marine basin in the Canadian High Arctic, the stable oxygen and hydrogen isotope data coupled with hydrochemical data showed the brine rejection during ice formation as a mechanism for the generation of hypersalinity (Dugan and Lamoureux, 2011).…”

Section: Introductionmentioning

confidence: 98%

Isotope stratification of meromictic Lake Trekhtzvetnoe at the White Sea coast (Russia)

Vasil'chuk

Frolova

Касимов

et al. 2018

Ann. Limnol. - Int. J. Lim.

View full text Add to dashboard Cite

Postglacial isostatic uplift of the coastal zone resulted in the formation of isolated lakes along the shores of White Sea developed into permanently stratified (meromictic) lakes. On the basis of monitoring the vertical distribution of selected water quality parameters including temperature, salinity, concentration of major ions, microbial activity, dissolved oxygen and hydrogen sulfide, seasonal changes in the structure of the stratified water column are explored and governing factors identified. Lake Trekhtzvetnoe has a strong vertical stratification with seasonal mixing being confined to the upper part of the water column (mixolimnion). Сhemical water composition in the mixolimnion reflects the influence of precipitation with the underlying chemocline being defined by sharp gradients of salinity, dissolved oxygen and hydrogen sulphide levels. We found strong stable isotope stratification of water column in winter-early spring seasons of 2013, 2015 and 2016 and in the early autumn of 2015. The lowest isotope values were obtained near the surface in the mixolimnion. There was a gradual increase of isotope values towards the chemocline reaching the maximum in the bottom layer (monimolimnion). It was found that water in the mixolimnion was isotopically depleted in winter as a result of ice formation and isotopically enriched in the early autumn due to evaporation. Obvious desalination of mixolimnion and upper chemocline from 2012 to 2016 was possibly caused by the increase of precipitation and freshwater inflow in lake supply. Monimolimnion is a stable layer of high salinity, and it has enriched isotope composition that corresponds with meromictic structure of water column.

show abstract

The chemical development of a hypersaline coastal basin in the High Arctic

Cited by 13 publications

References 52 publications

Under‐ice salinity transport in low‐salinity waterbodies

Under‐ice salinity transport in low‐salinity waterbodies

Study of microbial communities in redox zone of meromictic lakes isolated from the White Sea using spectral and molecular methods

Isotope stratification of meromictic Lake Trekhtzvetnoe at the White Sea coast (Russia)

Contact Info

Product

Resources

About