Hydrostatic Densitometer for Monitoring Density in Freshwater to Hypersaline Water Bodies
Density, temperature, salinity, and hydraulic head are physical scalars governing the dynamics of aquatic systems. In coastal aquifers, lakes, and oceans, salinity is measured with conductivity sensors, temperature is measured with thermistors, and density is calculated. However, in hypersaline brin...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-07-01
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| Series: | Water |
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| Online Access: | https://www.mdpi.com/2073-4441/13/13/1842 |
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| author | Ziv Mor Hallel Lutzky Eyal Shalev Nadav G. Lensky |
| author_facet | Ziv Mor Hallel Lutzky Eyal Shalev Nadav G. Lensky |
| author_sort | Ziv Mor |
| collection | DOAJ |
| description | Density, temperature, salinity, and hydraulic head are physical scalars governing the dynamics of aquatic systems. In coastal aquifers, lakes, and oceans, salinity is measured with conductivity sensors, temperature is measured with thermistors, and density is calculated. However, in hypersaline brines, the salinity (and density) cannot be determined by conductivity measurements due to its high ionic strength. Here, we resolve density measurements using a hydrostatic densitometer as a function of an array of pressure sensors and hydrostatic relations. This system was tested in the laboratory and was applied in the Dead Sea and adjacent aquifer. In the field, we measured temporal variations of vertical profiles of density and temperature in two cases, where water density varied vertically from 1.0 × 10<sup>3</sup> kg·m<sup>−3</sup> to 1.24 × 10<sup>3</sup> kg·m<sup>−3</sup>: (i) a borehole in the coastal aquifer, and (ii) an offshore buoy in a region with a diluted plume. The density profile in the borehole evolved with time, responding to the lowering of groundwater and lake levels; that in the lake demonstrated the dynamics of water-column stratification under the influence of freshwater discharge and atmospheric forcing. This method allowed, for the first time, continuous monitoring of density profiles in hypersaline bodies, and it captured the dynamics of density and temperature stratification. |
| first_indexed | 2024-03-10T09:48:51Z |
| format | Article |
| id | doaj.art-691810eb82504de788cd0a0ae7afa950 |
| institution | Directory Open Access Journal |
| issn | 2073-4441 |
| language | English |
| last_indexed | 2024-03-10T09:48:51Z |
| publishDate | 2021-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Water |
| spelling | doaj.art-691810eb82504de788cd0a0ae7afa9502023-11-22T02:55:07ZengMDPI AGWater2073-44412021-07-011313184210.3390/w13131842Hydrostatic Densitometer for Monitoring Density in Freshwater to Hypersaline Water BodiesZiv Mor0Hallel Lutzky1Eyal Shalev2Nadav G. Lensky3Geological Survey of Israel, Jerusalem 9692100, IsraelGeological Survey of Israel, Jerusalem 9692100, IsraelGeological Survey of Israel, Jerusalem 9692100, IsraelGeological Survey of Israel, Jerusalem 9692100, IsraelDensity, temperature, salinity, and hydraulic head are physical scalars governing the dynamics of aquatic systems. In coastal aquifers, lakes, and oceans, salinity is measured with conductivity sensors, temperature is measured with thermistors, and density is calculated. However, in hypersaline brines, the salinity (and density) cannot be determined by conductivity measurements due to its high ionic strength. Here, we resolve density measurements using a hydrostatic densitometer as a function of an array of pressure sensors and hydrostatic relations. This system was tested in the laboratory and was applied in the Dead Sea and adjacent aquifer. In the field, we measured temporal variations of vertical profiles of density and temperature in two cases, where water density varied vertically from 1.0 × 10<sup>3</sup> kg·m<sup>−3</sup> to 1.24 × 10<sup>3</sup> kg·m<sup>−3</sup>: (i) a borehole in the coastal aquifer, and (ii) an offshore buoy in a region with a diluted plume. The density profile in the borehole evolved with time, responding to the lowering of groundwater and lake levels; that in the lake demonstrated the dynamics of water-column stratification under the influence of freshwater discharge and atmospheric forcing. This method allowed, for the first time, continuous monitoring of density profiles in hypersaline bodies, and it captured the dynamics of density and temperature stratification.https://www.mdpi.com/2073-4441/13/13/1842hydrostatic densitometerdensity measurementhypersaline brinecoastal aquiferfresh–saline water interfacediluted plume |
| spellingShingle | Ziv Mor Hallel Lutzky Eyal Shalev Nadav G. Lensky Hydrostatic Densitometer for Monitoring Density in Freshwater to Hypersaline Water Bodies Water hydrostatic densitometer density measurement hypersaline brine coastal aquifer fresh–saline water interface diluted plume |
| title | Hydrostatic Densitometer for Monitoring Density in Freshwater to Hypersaline Water Bodies |
| title_full | Hydrostatic Densitometer for Monitoring Density in Freshwater to Hypersaline Water Bodies |
| title_fullStr | Hydrostatic Densitometer for Monitoring Density in Freshwater to Hypersaline Water Bodies |
| title_full_unstemmed | Hydrostatic Densitometer for Monitoring Density in Freshwater to Hypersaline Water Bodies |
| title_short | Hydrostatic Densitometer for Monitoring Density in Freshwater to Hypersaline Water Bodies |
| title_sort | hydrostatic densitometer for monitoring density in freshwater to hypersaline water bodies |
| topic | hydrostatic densitometer density measurement hypersaline brine coastal aquifer fresh–saline water interface diluted plume |
| url | https://www.mdpi.com/2073-4441/13/13/1842 |
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