Abstract
Horizontal mixing processes in the hypolimnion of the western part of Lake Constance are studied by measuring the dispersion of a sulfur hexafluoride (SF6) tracer plume. Only 1 liter gaseous SF6 (STP) was released at a central hypolimnic depth of 60 m in August 1990. Over a period of 3 months the horizontal dispersion of the tracer plume was measured by 19 surveys using a new, vertically integrating sampling device. The observed horizontal dispersion is marked by strong storm-induced stirring events. Nevertheless mean turbulent diffusion coefficients for the whole period can be computed. They rise about linear from 0.7 ⋅ 105 cm2/s to 3.0 ⋅ 105 cm2/s with the distance from the western end of the lake. For the hypolimnion of Überlingersee, a sill-separated basin in the western part of Lake Constance, a simple budget model gives an exchange time of 67 ± 6 days with the main basin (Obersee).
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Gaedke, U., and M. Schimmele, 1991. Internal seiches in Lake constance: influence on plankton abundance at a fixed sampling site. J. Plankton Res. 13:743–754.
Heinz, G., 1990. Mischungs- und Strömungsverhältnisse im Westteil des Bodensees. Ph. D. Thesis, Institut für Umweltphysik, University of Heidelberg, 146 pp.
Internationale Gewässerschutzkommission für den Bodensee (ed.), 1990. Karte der internationalen Bodensee-Tiefenvermessung 1:50000. Publisher: Landesvermessungsamt Baden-Württemberg, Stuttgart.
Ledwell, J.R., and A.J. Watson, 1991. The Santa Monica Basin tracer experiment: A study of diapycnal and isopycnal mixing. J. geophys. Res. 96:8695–8718.
Ledwell, J.R., A.J. Watson, and C.S. Law, 1993. Evidence for slow mixing across the pycnocline from an open-ocean tracer-release experiment. Nature 364:701–703.
Maiss, M., 1992. Schwefelhexafluorid (SF6) als Tracer für Mischungsprozesse im westlichen Bodensee. Ph. D. Thesis, Institut für Umweltphysik, University of Heidelberg, 219 pp.
Maiss, M., J. Ilmberger, and K.O. Münnich, 1994. Vertical mixing in Überlingersee (Lake Constance) traced by SF6 and heat. Aquatic Sciences, this issue.
Maiss, M., and I. Levin, 1994. Global increase of SF6 observed in the atmosphere. Geophys. Res. Lett. 21:569–572.
Mortimer, C.H., 1979. Strategies for coupling data collection and analysis with dynamic modelling of lake motions. In: W.H. Graf and CH. Mortimer (eds.), “Hydrodynamics of lakes”, Elsevier Scientific Publishing Company, Amsterdam: 183–213
Murthy, C.R., 1976. Horizontal diffusion characteristics in Lake Ontario. J. Phys. Oceanogr. 6:76–84.
Neubert, R., 1991. Untersuchung der winterlichen Mischung im Bodensee mit Tritium,3Helium und anderen Spurenstoffen. Diplomarbeit, Institut für Umweltphysik, University of Heidelberg, 133 pp.
Okubo, A., 1971. Oceanic diffusion diagrams. Deep-Sea Res. 18:789–802.
Penk, A., 1894. Morphometrie des Bodensees. Festschrift der Geograph. Gesellschaft in München zur Feier ihres 25jährigen Bestehens, München:119–156.
Schimmele, M., 1993. Anregung interner Seiches im Bodensee durch den Wind. Ph. D. Thesis, Institut für Umweltphysik, University of Heidelberg, 161 pp.
Schlatter, J., M. Hofer, and D.M. Imboden, 1990. Die Verwendung von Schwefelhexafluorid zum Studium von Transportprozessen in Seen. Gas-Wasser-Abwasser 70/1:36–42.
Wanninkhof, R., J.R. Ledwell, and W.S. Broecker, 1985.Gas exchange — wind speed relation measured with sulfur hexafluoride on a lake. Science 227:1224–1226.
Wanninkhof, R., J.R. Ledwell, W.S. Broecker, and M. Hamilton, 1987. Gas exchange on Mono Lake and Crowley Lake, California. J. geophys. Res. 92:567–580.
Wanninkhof, R., J.R. Ledwell, and A.J. Watson, 1991. Analysis of sulphur hexafluoride in seawater. J. geophys. Res. 96:8733–8740.
Zenger, A., 1989. Ursachen und Auswirkungen von Transport und Mischungsprozessen im westlichen Bodensee. Ph. D. Thesis. Institut für Umweltphysik, University of Heidelberg, 137 pp.
Zenger, A., J. Ilmberger, G. Heinz, M. Schimmele, and K.O. Münnich, 1989. Untersuchungen zur Struktur der internen Seiches des Bodensees. Wasserwirtschaft 79:616–624.
Zenger, A., J. Ilmberger, G. Heinz, M. Schimmele, P. Schlosser, D. Imboden, and K.O. Münnich, 1990. Behavior of a medium-sized basin connected to a large lake. In: M.M. Tilzer, and C. Serruya (eds.), “Large Lakes — Ecological Structure and Function”, Springer-Verlag, Berlin Heidelberg:133–155.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Maiss, M., Ilmberger, J., Zenger, A. et al. A SF6 tracer study of horizontal mixing in Lake Constance. Aquatic Science 56, 307–328 (1994). https://doi.org/10.1007/BF00877179
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00877179