Lake ice formation processes and thickness evolution at Lake Abashiri, Hokkaido, Japan

Lake-ice properties at Lake Abashiri, Hokkaido, Japan, were examined using field observations and a 1-D thermodynamic model to clarify formation processes at mid-latitudes subject to significant snowfall as well as moderate air temperature. At all lake sites examined, the ice comprised two distinct...

Full description

Bibliographic Details
Published in:Journal of Glaciology
Main Authors: YU OHATA, TAKENOBU TOYOTA, TAKAYUKI SHIRAIWA
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press 2016
Subjects:
Online Access:https://doi.org/10.1017/jog.2016.57
https://doaj.org/article/7f788be468e24ae19c1e55369504241a
Description
Summary:Lake-ice properties at Lake Abashiri, Hokkaido, Japan, were examined using field observations and a 1-D thermodynamic model to clarify formation processes at mid-latitudes subject to significant snowfall as well as moderate air temperature. At all lake sites examined, the ice comprised two distinct layers: a snow ice (SI) layer on top and a congelation ice (CI) layer below. The SI layer occupied as much as 29–73% of the total ice thickness, a much greater fraction than that reported for lakes at Arctic high latitudes. In the model, the CI growth rate was estimated using the traditional heat budget method, while the SI growth rate was calculated assuming the excessive snowfall from the isostatic balance is converted to SI by a snow compression rate (β) with the surface melting rate added when the surface heat budget becomes positive. By tuning the value of β to the observational results of SI thickness, the model outcome successfully reproduced the observational thicknesses of CI and SI, and the break-up date of the lake. Essentially, the model findings show how snow and its formation into SI reduce, by about half, the seasonal variability of total ice thickness.