Thermal dynamics of sub-arctic Lake Lagarfljót, Iceland

Abstract

Water temperature plays an important role in lake environments.Not only does temperature affect the chemical composition of water, but thermal processes also heavily influence the fate and transport of materials. This paper characterizes the thermal dynamics of Lake Lagarfljót, one of Iceland´s largest and deepest lakes. Results from 10 year temperature records suggest that despite low summer temperatures and strong winds, a weak summer stratification lasting two months sets a stage for unusually slow internal seiches. The bottom stirring and oxygen renewal from these seiches is reinforced by sediment rich plunging inflow. Differential heating and cooling may contribute to lateral transport of landborn urban materials from littoral to pelagic regions of the lake. This work highlights the importance of further study of sub-arctic lake thermal processes, which will be conducted in the coming years.