The Heat Balance of Two Antarctic LAKES1
Abstract
The thermal structures of Lakes Vanda and Bonney in Victoria Land, Antarctica, are examined and the heat balance of Lake Vanda evaluated. Both lakes are permanently ice‑covered and have high salt concentrations that increase with depth. The deep water of Lake Vanda is very warm (25C), while that of Lake Bonney is cold (−2.8C). Lake Vanda gains heat from solar radiation and by conduction from the bottom. All the heat gained is accounted for by melting of the undersurface of the ice and evaporation from the upper surface. Changes in sensible heat storage in the water in both lakes are extremely small. Lake Vanda has four layers of constant density water that are maintained by convective circulation driven by heating from below. The existence of a strong circulation in the thickest of these layers is demonstrated by a radioactive tracer experiment that revealed a horizontal current of 1 cm/sec at 20 m and some vertical mixing. No evidence of convective activity was found in Lake Bonney. Hypotheses put forth by other workers to explain the warm water of Lake Vanda by solar heating alone and by subsurface advection from thermal springs are considered and rejected.
- Publication:
-
Limnology and Oceanography
- Pub Date:
- April 1964
- DOI:
- 10.4319/lo.1964.9.3.0412
- Bibcode:
- 1964LimOc...9..412R