Abstract: The temporal and spatial distributions of sea fog based on the data at Yingkou and Xiongyue weather stations along the north coast of the Bohai Sea in China were analyzed. The results indicated that the numbers of thick fog days from 1954 to 2007 at two weather stations are in the increasing trends, especially in nighttime, and it passes the significance test with 0.05 levels at Xiongyue weather station. The numbers of light fog days at two weather stations are in the increasing trend from 1954 to 2007, so are the numbers of light fog days in daytime and in nighttime, and they all pass the significance test with 0.01 levels. The monthly thick fog days mainly appear from November to February along the north coast of the Bohai Sea in China. The hourly sea fog concentrates in the morning, especially from 6:00 to 8:00 (BST).

Key words: The northern Bohai Sea, Near coast, Fog, Characterization, The north of the Bohai Sea in China, Near the coast, Fog, Comparison analysis