Thermal modeling of three lakes within continuous permafrost zone in
Alaska using LAKE 2.0 model
Abstract
Lakes in the Arctic are important reservoirs of heat with much
lower albedo and larger absorption of solar radiation than surrounding
tundra vegetation. Under climate warming scenarios, we expect Arctic
lakes to further accelerate thawing underlying permafrost. Previous
studies of Arctic lakes have focused on ice cover and thickness, the ice
decay process, catchment hydrology, lake water balance, and eddy
covariance measurements, but little work has been done in the Arctic to
model lake heat balance. We applied the LAKE model to simulate water
temperatures in three Arctic lakes in Northern Alaska over several
years. The LAKE model is a one-dimensional that explicitly solves
vertical profiles of water state variables on a grid. We used a
combination of meteorological data from local and remote weather
stations, as well as data derived from remote sensing, to drive the
model. We validated simulated water temperatures with data of observed
lake temperatures at several depths. Our validation of the LAKE model
completes a necessary step toward modeling changes in Arctic lake ice
regimes, lake heat balance, and thermal interactions with permafrost.
Our results showed that winter precipitation and lake ice plays an
important role in forming water temperatures over the winter period. Our
findings suggest that reduction in the lake ice thickness and ice time
period could lead to more heat storage by lakes and further warming of
the Arctic.