Meteorological characteristics of fog occurrences around the Nakdong River in the Korean Peninsula: a case study at Gangjeong-Goryeong Weir

Monday, 15 December 2014
Park jun Sang, Kim Kyu Rang, Lim Yun Kyu, Cho Chang Bum and Choi Byoung Choel, National Institute of Meteorological Research, Seogwipo-si, South Korea
Radiation fog is typically observed in the inland area. However, different fog types are observed around water body. Fog formation (visibility <1 km) was observed using a transmissometer around Gangjeong-Goryeong Weir over the Nakdong River along with air temperature, relative humidity, surface temperature, and wind speed and direction. The observed data is 2 years long from January 1, 2012 to December 31, 2013 with a missing rate of 2.67%. In addition, visibility at Deagu Weather Station (DWS) and water temperature at Gangjeong-Goryeong Weir data were used.
The meteorological characteristics at the Weir were observed as follows: summer (winter) temperature was higher (lower) than normal year; humidity was higher than that at DWS; and soil temperature was lower than water temperature that at Gangjeong-Goryeong Weir and soil temperature that at DWS. The water temperature at the Weir increased during the last 5 years.
Fog formation at the Wier was most frequently observed in the fall - generally during dawn or morning. When the fog occurs, wind direction was Southwest and soil temperature was lower than air temperature. Evaporation fog was the main type out of four fog types (radiation, advection, evaporation, and front) considered. This study will analyze the time series of the meteorological factors of the four fog types to assess the meteorological conditions during the fog formation.