The influence of water column density shifts on vertical transport of dissolved chemicals: applications to problems of monitoring and predicting water resource quality

Citation
V. Kushnir et al., The influence of water column density shifts on vertical transport of dissolved chemicals: applications to problems of monitoring and predicting water resource quality, WATER SCI T, 42(1-2), 2000, pp. 341-346
Citations number
8
Categorie Soggetti
Environment/Ecology
Journal title
WATER SCIENCE AND TECHNOLOGY
ISSN journal
02731223 → ACNP
Volume
42
Issue
1-2
Year of publication
2000
Pages
341 - 346
Database
ISI
SICI code
0273-1223(2000)42:1-2<341:TIOWCD>2.0.ZU;2-2
Abstract
A steep gradient density layer (density shift) in a water column often form s due to intense summer heating of the surface and wind mixing the upper la yer. It influences the vertical transport of chemicals and pollutants, due to the significant power generated, overcoming Archimedes forces. The mecha nism of Vertical transport of dissolved chemicals through the density shift is connected with the stochastic formation of local turbulent structures - "turbulence flares", which arise because of shifts of current speed in int ernal waves and eddy-wave formation of the "billows" type. Analyses of data from the Black Sea and Lake Kinneret indicate the universal character for conditions of the dimensionless dependence of logRi = f(Z/Zm) and logRi = f (2logN/Nm), where Ri = the Richardson number, Z = depth, Zm = the depth of the Brunt-Vaisala frequency N(Z) maximum (Nm). A high positive correlation (R = 0.75) between logRi and 2 logN/Nm values allows the use of vertical de nsity profile data (water temperature) for estimating the vertical fluxes o f chemical elements and pollutants. The simplicity of measurement and avail ability of data on density structure of water basins provide means for effe ctive monitoring of vertical transport of chemical elements and pollutants under various conditions.