Kirillin_etal(2015).pdf (1.78 MB)
Axisymmetric circulation driven by marginal heating in ice-covered lakes
journal contribution
posted on 2023-05-18, 11:03 authored by Kirillin, GB, Alexander Forrest, Graves, KE, Andrew FischerAndrew Fischer, Engelhardt, C, Laval, BEBelow the temperature of maximum density (TMD) in freshwater lakes, heating at the lateral margins produces gravity currents along the bottom slope, akin to katabatic winds in the atmosphere and currents on continental shelves. We describe axisymmetric basin-scale circulation driven by heat flux at the shorelines in polar Lake Kilpisjärvi. A dense underflow originating near the shore converges toward the lake center, where it produces warm upwelling and return flow across the bulk of lake water column. The return flow, being subject to Coriolis force, creates a lake-wide anticyclonic gyre with velocities of 2–4 cm s-1. While warm underflows are common on ice-covered lakes, the key finding is the basin-scale anticyclonic gyre with warm upwelling in the core. This circulation mechanism provides a key to understanding transport processes in (semi) enclosed basins subject to negative buoyancy flux due to heating (or cooling at temperatures above TMD) at their lateral boundaries.
Funding
International Network for Terrestrial Research and Monitoring in the Arctic
History
Publication title
Geophysical Research LettersVolume
42Issue
8Pagination
2893-2900ISSN
0094-8276Department/School
Australian Maritime CollegePublisher
Amer Geophysical UnionPlace of publication
2000 Florida Ave Nw, Washington, USA, Dc, 20009Rights statement
Copyright 2015 American Geophysical UnionRepository Status
- Restricted