Analysis of a Sea Fog Episode at King George Island, Antarctica

Abstract

In this study, a marine fog episode at King George Island off the Antarctic Peninsula from 26–30 January 2017 was investigated using surface observations, upper-air soundings, and re-analysis data as well as the air mass backward trajectory method. The marine fog episode resulted from an approaching low-pressure system, was maintained at high wind speeds, and quickly dissipated when the low-pressure system passed the observation site. During this episode, cloud lay existed above the fog and stratus, the atmosphere was stably stratified for 1600 m, and the air close to the surface was more mixed than air in the upper layer. The air-sea temperature difference (ASTD) of 1–2 °C and a strong surface wind parallel to the gradient of SST were two important factors in the formation and maintenance of the marine fog near the Antarctic region. The convergence of flux for both water vapor and heat during the fog episode was also discussed.