In late March, 2012, a large bank of low clouds hung over the Yellow Sea, extending hundreds of kilometers from north to south. The eastern edge of the fog closely hugged the coast of North Korea and southern South Korea, while the western edge remained off the shore just north of Shanghai, China.
Sea fog is common in the Yellow Sea, with fog reported off the coast of China on an average of 50 days a year, primarily in the period of April through July. In early spring, a temperature inversion forms about 100-350 m above the sea surface. As the land warms faster than the sea the prevailing winds push warm continental air over the Yellow Sea, making conditions right for the formation of fog. Such banks of low clouds (fog) often last a day or more before clearing, and can make hazardous conditions for ships sailing in the vicinity.
The Moderate Resolution Imaging Spectroradiometer (MODIS) acquired this true-color image on March 28, 2012, just a few days ahead of the typical beginning of sea fog season.