Local meteorological and synoptic characteristics of fogs formed over Incheon international airport in the west coast of Korea

Abstract

Fogs observed over Incheon international airport (IIA) in the west coast of Korea from January 2002 to August 2006 are classified into categories of coastal fog, cold sea fog, and warm sea fog based on the areal extent of the fogs and the difference between the air temperature (T ) and the SST, i.e., cold sea fog if TSST = T −SST > 0• C and warm sea fog if TSST < 0 • C. The numbers of coastal, cold, and warm sea fog cases are 64, 26, and 9. Coastal fogs form most frequently in winter, while cold sea fogs occur mostly in summer and warm sea fogs are observed from January to May but not in November and December. On average the air gets colder by 1.6• C during the three hours leading up to the coastal fog formation, and an additional cooling of 1.1• C occurs during the fog. The change in the dew point temperature (T d ) is minimal except during the fog (0.6• C). Decreases in T for the cold and warm sea fogs are relatively smaller. The average T d is higher than SST during the cold sea fog periods but this T d is more than 4• C higher than that for the corresponding non-fog days, suggesting that cold sea fogs be formed by the cooling of already humid air (i.e., T d >SST). Increases of T d are significant during the warm sea fog periods (1.4• C), implying that efficient moisture supply is essential to warm sea fog formation. Four major synoptic patterns are identified in association with the observed fogs. The most frequent is a north Pacific high that accounts for 38% of cases. Surface or upper inversions are present in 77%, 69%, and 81% of the fog periods for coastal, cold, and warm sea fogs, respectively.Key words: costal fogs, sea fogs, west coast of Korea, meteorological and synoptic characteristics Citation: Kim, C. K., and S. S. Yum, 2010: Local meteorological and synoptic characteristics of fogs formed over Incheon international airport in the west coast of Korea.

Marine Boundary Layer Structure for the Sea Fog Formation off the West Coast of the Korean Peninsula

“…Recently, KIM and YUM (2010) examined statistical characteristics of the sea fogs that form over the other side of the Yellow Sea off the Korean west coast. They classified sea fogs as cold and warm sea fogs, based on the differences between air temperature (T) and sea surface temperature (SST) (TSST = T-SST) at the onset time of sea fog formation (i.e., cold sea fog if TSST [ 0°C and warm sea fog if TSST \ 0°C) and associated the occurrence statistics with relevant meteorological variables.…”

“…This study is an extension of the work by KIM and YUM (2010). Here we examine the physical processes that are relevant to sea fog formation over the eastern Yellow Sea off the Korean coast.…”

A Numerical Study of Sea-Fog Formation over Cold Sea Surface Using a One-Dimensional Turbulence Model Coupled with the Weather Research and Forecasting Model

“…Meanwhile, Holtslag et al (1990) and Koracin et al (2001) considered an air column moving along a trajectory simulated by a 3D regional model and studied atmospheric boundary-layer modification caused by the change in surface condition. Kim and Yum (2010) examined the statistical characteristics of sea fog that forms over the Yellow Sea off the west coast of Korea. They classified 35 sea-fog occurrences into 26 cases of cold sea fog and nine cases of warm sea fog, based on the difference, T, between air temperature (T ) and sea-surface temperature (SST) ( T = T − SST ) three hours before the onset of fog formation (i.e., cold sea fog for T > 0 and warm sea fog for T < 0) and linked the occurrence statistics with relevant meteorological variables.…”

A Fog Event off the Coast of the Hangzhou Bay during Meiyu Period in June 2013

“…The formation, maintenance and dissipation of fog are associated with physical processes, ranging from the large/synoptic scale (e.g., advection) to meso-scale (e.g., land-sea breeze) and to micro-scale (e.g., droplets) (Gultepe et al, 2007;Koračin et al, 2014). Local meteorological (e.g., wind direction and speed) and hydrological (e.g., sea surface temperature, SST) conditions are essential for fog formation near coastal regions (Huang et al, 2010;Kim and Yum, 2010). For example, influenced by the Pacific high-pressure system, the sinking of the cloud-bottom to sea surface may lead to fog along the western coast of U.S. (Koračin et al, 2001;Lewis et al, 2004).…”

“…Fog frequently occurs under the southeasterly warm/moist air advection along the Chinese coast of the South China Sea, the East China Sea and the Yellow Sea (Zhang et al, 2009;Huang et al, 2015), and due to strong tidal mixing off the western coast of the Korean Peninsula (Kim and Yum, 2010).…”