Interrelation of quality parameters of surface waters in five tidewater glacier coves of King George Island, Antarctica

Temporal and spatial variations of the hydrogen peroxide accumulation were measured in off-shore waters and in intertidal rockpools near Jubany Station, King George Island, South Shetland Islands. As H2O2 photoformation is mainly driven by the short wavelength radiation in the UV-B and the UV-A range of the solar spectrum, the study was conducted between the beginning of October and the end of December 1995, the period of Antarctic spring ozone depletion. Wet deposition of H2O2 containing snow was identified as a major source of hydrogen peroxide in the surface waters of Potter Cove. As the concentrations of dissolved organic carbon (DOC) in Potter Cove surface waters were low (121 ± 59 μmol Cl−1), when compared to the highly eutrophicated waters on the German Wadden coast (6000–7000 μmol Cl−1), direct UV-induced DOC photo-oxidation was of only limited significance in the Antarctic sampling site. Nonetheless, under experimental conditions, H2O2 photoformation in Potter Cove surface waters amounted to 90 ± 40 nmol H2O2 h−1 l−1 under a UV-transparent quartz plate. When high energy UV-B photons were cut-off by a WG320 filter formation continued at a rate of 66 ± 29 nmol H2O2 h−1 l−1 due to UV-A and visible light photons. Samples from freshly deposited snow contained between 10 000 and 13 600 nmol H2O2 l−1, and a snowfall event in mid November resulted in a maximum concentration of 1450 nmol H2O2 l−1 in the upper 10 cm layer of Potter Cove surface waters. Maximal H2O2 concentrations in intertidal rockpools were even higher and reached up to 2000 nmol H2O2 l−1 after the snowfall event. During a grid survey on December 17 1995, H2O2 concentrations and salinity displayed a north to south gradient, with higher concentrations and PSU at the south coast of the cove. The reasons for this spatial inhomogenety are as yet unknown, but may relate to a minor local input of photo-reactive organic matter from creeks entering the cove in the south-east, as well as to waste water discharge from the station, located on the south beach.

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Phytoplankton distribution and abundance as related to a frontal system north of Elephant Island, Antarctica

Antarctic Science ◽

10.1017/s0954102093000057 ◽

1993 ◽

Vol 5 (1) ◽

pp. 25-36 ◽

Cited By ~ 9

Author(s):

E. Walter Helbling ◽

Anthony F. Amos ◽

Nelson Silva S. ◽

Virginia Villafañe ◽

Osmund Holm-Hansen

Keyword(s):

Surface Waters ◽

Phytoplankton Community ◽

Floristic Composition ◽

Shelf Break ◽

Water Type ◽

King George Island ◽

Phytoplankton Distribution ◽

Exact Position ◽

Continental Shelf Break ◽

Elephant Island

During January-March, 1991, the distribution and floristic composition of the phytoplankton around Elephant Island, Clarence Island and the northern end of King George Island were determined in relation to physical oceanographic conditions and to proximity of the shelf-break and continental slope. The study area included 180 stations, and c. 5400 km of transects providing continuous measurements of salinity, temperature, beam attenuation, and chlorophyll a (chl a) concentrations in surface waters. The richest phytoplankton areas (2-4 μg chl a 1-1) were generally found associated with a strong salinity front, extending north of King George Island to north of Elephant and Clarence Islands. Data on the phytoplankton community suggest that shelf waters were charaterized by low biomass and a nanoplankton population, while in and just north of the front the biomass increased and there was a shift to a diatom-dominated microplankton population. This is thought to be related to increased stability of the water column just north of the front. The salinity front ran more or less parallel to the continental shelf-break, but its exact position varied during the period of study. It was generally associated with transition water (Type II) or with Weddell-Scotia Confluence water (Type III).

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Modelling the impact of iceberg melt on glacier-ocean interaction, east Greenland

10.5194/egusphere-egu2020-8663 ◽

2020 ◽

Author(s):

Ben Davison ◽

Tom Cowton ◽

Finlo Cottier ◽

Andrew Sole

Keyword(s):

Surface Waters ◽

General Circulation ◽

Circulation Model ◽

Freshwater Flux ◽

Near Surface ◽

Distributed Source ◽

East Greenland ◽

Tidewater Glacier ◽

Modelling Studies ◽

The Impact

<p>The melting of icebergs within Greenland&#8217;s iceberg-choked fjords provides a large and distributed source of liquid freshwater throughout the year. However, the impact of this freshwater flux on fjord properties and circulation remains unclear, in part because icebergs have typically been neglected in modelling studies that seek to examine interaction between glacier and fjord processes. Here, we modify a general circulation model to simulate the impact of iceberg submarine melting within Kangerdlugssuaq and Sermilik fjords in east Greenland, home to two of Greenland&#8217;s largest glaciers. We find that iceberg submarine melting results in cooling of up to 5&#176;C and freshening of up to 0.6 psu throughout the upper 100-200 metres of both fjords, compared to experiments without icebergs. The resulting freshwater flux, which is of the order of hundreds of cumecs, is capable of driving a weak overturning circulation. This augments the runoff-driven circulation at depth but can oppose the up-fjord flow of warm near-surface waters, resulting in an increase in up-fjord heat flux at depth but a decrease near the surface. By increasing subsurface iceberg melt rates, ocean warming will therefore expedite iceberg deterioration within ice m&#233;lange and may further increase ocean thermal forcing of tidewater glacier grounding lines. Our results highlight the significant impact that icebergs have on fjord water properties and circulation in Greenland&#8217;s iceberg-choked fjords, demonstrating the importance of including these processes in studies that seek to examine interactions between the ice sheet and the ocean.</p>

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Proximal VIS-NIR spectrometry to retrieve substance concentrations in surface waters using partial least squares modelling

Water Science & Technology Water Supply ◽

10.2166/ws.2018.177 ◽

2018 ◽

Vol 19 (4) ◽

pp. 1204-1211 ◽

Cited By ~ 2

Author(s):

A. Wagner ◽

S. Hilgert ◽

T. Kattenborn ◽

S. Fuchs

Keyword(s):

Remote Sensing ◽

Water Quality ◽

Surface Water ◽

Least Squares ◽

Partial Least Squares ◽

Surface Waters ◽

Suspended Solids ◽

Quality Parameters ◽

Water Bodies ◽

Surface Water Bodies

Abstract Many water quality parameters such as concentrations of suspended matter, nutrients and algae directly or indirectly change the electromagnetic reflectance and transmission properties of surface water bodies. Optical measurement approaches have shown great potential to partially substitute water sampling and laboratory analyses, but are obstructed by limited flexibility or high maintenance demands. In order to overcome these problems and to bridge the gap between in situ and remote sensing measurements, the use of close-range, above-surface reflectance measurements in the VIS-NIR domain to measure water quality parameters in surface water bodies was investigated. Remote sensing reflectance in a 1 m³ water tank with increasing, known concentrations of suspended solids was measured. A partial least squares model was trained to predict concentrations from reflectance curves, which performed well, considering the wide range of concentrations and illumination conditions (R²cal = 0.96, R²val = 0.97). The approach was then transferred to the field and further parameters were tested. Using a semi-autonomous spectrometer mounted to a boom stand on a motor boat, we traced substance concentrations in close intervals along a longitudinal gradient from inflow to dam in a drinking water reservoir in Brazil. The method is suitable for parameters directly influencing the reflection properties of the water body (e.g. suspended solids (R²cal = 0.93), chlorophyll-a (R²cal = 0.74)), or for parameters closely related to those (e.g. total phosphorus (R²cal = 0.97)). For chemical oxygen demand, the method is not well suited (R²cal = 0.14, R²val = 0.45). Once calibrated to the local conditions, the spectrometer can be used stationary or on moving platforms to map and monitor surface waters. The integration of the procedure into acoustic and imaging techniques is further investigated.

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Study of Electric Conductivity of Urban Stream Water Polluted with Municipal Effluents

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.641-642.1172 ◽

2014 ◽

Vol 641-642 ◽

pp. 1172-1175 ◽

Cited By ~ 5

Author(s):

Alexandr N. Chusov ◽

Ekaterina A. Bondarenko ◽

Maria Ju. Andrianova

Keyword(s):

Electric Conductivity ◽

Surface Waters ◽

Stream Water ◽

Correlation Coefficients ◽

Quality Parameters ◽

Urban Stream ◽

Waste Waters ◽

Specific Electric Conductivity ◽

Water Conductivity ◽

Fresh Surface

Specific electric conductivity of water samples in a polluted urban stream was compared with other water quality parameters such as concentration of inorganic carbon, total organic carbon, and total nitrogen. Increasing of water conductivity 1.3...10 times was observed downstream canalization outlets discharging drainage waters together with residential waste waters from inhabited district of city. In some periods water conductivity showed good correlation with pollutants concentration such as TN and IC (with correlation coefficients 0.54...0.96). The received data show that electric conductivity can be used for revealing waste waters pollution in fresh surface waters.

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Water quality parameters controlling the photodegradation of two herbicides in surface waters of the Columbia Basin, Washington

Chemosphere ◽

10.1016/j.chemosphere.2013.05.050 ◽

2013 ◽

Vol 93 (9) ◽

pp. 1734-1741 ◽

Cited By ~ 3

Author(s):

Olha S. Furman ◽

Miao Yu ◽

Amy L. Teel ◽

Richard J. Watts

Keyword(s):

Water Quality ◽

Surface Waters ◽

Quality Parameters ◽

Water Quality Parameters ◽

Columbia Basin

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Evaluation of Surface Waters Quality Obtained from Different Sources of Mymensingh District of Bangladesh

The Agriculturists ◽

10.3329/agric.v13i1.26563 ◽

2016 ◽

Vol 13 (1) ◽

pp. 189-195

Author(s):

Zannatul Ferdous ◽

M F Haque ◽

M A Hosain ◽

M M Rahman ◽

Abu Sayed

Keyword(s):

Heavy Metals ◽

Surface Water ◽

Surface Waters ◽

Chemical Properties ◽

Quality Parameters ◽

University Campus ◽

Standard Value ◽

Metal Properties ◽

Total Dissolved Solid ◽

Different Sources

The present study was conducted to assess some chemical properties and heavy metals of surface waters collected from different sources at Bangladesh Agricultural University Campus and Mymensingh Sadar Upazila for common use. Twelve water samples were collected from 4 different locations during February to April 2011 for analyzing their chemical quality parameters. The recorded values of pH, EC (Electrical Conductivity), TDS (Total Dissolved Solid), DO (Dissolved Oxygen), As, Pb and Fe were found to range from 6.153 to 7.043, 0.194 to 0.679 mS/cm,106.333 to 389.333 ppm, 4.433 to 4.9 ppm, 0.064 to 1.756 ppb, 0.00053 to 0.00083 ppm and 0.567 to 1.795 ppm, respectively. pH and TDS of the surface water were within the standard value but other parameters such as As, Pb, and Fe were significantly higher than the standard for drinking water. The correlation analysis among chemical and heavy metal properties indicated that all the parameters had significant contribution to pollute the water except DO. The correlation between TDS and EC was strongly significant (r = 0.99**). pH showed positive significant correlation with EC and TDS. Fe showed negative (r = -0.636) significant correlation with As. The above findings show that the surface water in Mymensingh area is being gradually polluted by unplanned discharge of chemicals and heavy metals contained effluents. It might be concluded that the water is not so harmful yet for irrigation, aquaculture and livestock usage.The Agriculturists 2015; 13(1) 189-195

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