Oceanic heat fluxes under thin sea ice in Saroma-ko Lagoon, Hokkaido, Japan

Measurements of turbulent eddy fluxes of momentum and heat under growing thin sea ice in a pool artifically constructed in the ice sheet were made with a three-dimensional ultrasonic current meter and a fast-response temperature-conductivity meter in Saroma-ko Lagoon, Hokkaido, Japan, during the joint Japanese and Canadian Saroma-Resolute Study (SARES) project. The conductive heat flux across the ice sheet and the latent heat of newly formed ice in the pool were estimated from observing the changes in temperature gradients through the ice sheet and in ice thickness. The mean friction velocity was 0.13 cm s−1 over the one-day sampling period. The mean oceanic heat flux from the ocean to the growing thin ice, obtained from the eddy correlation method, was 75 W m−2 over the ice growing period at night and 33 W m−2 over the non-ice growing period in the day.