봄철 제주도 서부해역의 수괴 분포와 수온역전 특징
Distribution of Water Masses and Characteristics of Temperature Inversion in the Western Seas of Jeju Island in Spring
0
조회
0
다운로드
3
인용
0
참고문헌
키워드
초록
Using the results of CTD casts made in Spring from 2017 to 2021, in this study we investigated the water mass distribution and occurrence of temperature inversion in the western seas of Jeju Island in spring. The distribution of water masses was characterized by cold and fresh water in the northwest and warm and saline water in the southeast, forming a strong thermohaline front running in the southwest-to-northeast direction. Strong temperature inversion mainly occurred in the frontal boundary when the cold water intrudes beneath the warm water at depths of 30–50 m. Analysis of the mixing ratio demonstrated that Jeju Warm Water is dominantly distributed in the western seas of Jeju Island, but its ratio can be modified depending on the southward extension of Yellow Sea Cold Water (YSCW). Results of in situ measurement showed that in 2020, the YSCW largely expanded to the western seas of Jeju Island, occupying approximately 40 % of the mixing ratio. Due to the expansion of YSCW, a strong thermohaline front was formed in the study area, thereby causing thick and strong temperature inversion. On the other hand, in 2018 the mixing ratio of YSCW was minimum (~18%) during the study period of 2017–2021, and thus a relatively weak frontal boundary was formed, without the occurrence of temperature inversion. The observational results also suggest that the interannual changes of water mass distribution and the associated temperature inversion in the western seas of Jeju Island are closely related with wind-driven Yellow Sea circulation in spring, which is the summer monsoon transition period.
Abstract
Using the results of CTD casts made in Spring from 2017 to 2021, in this study we investigated the water mass distribution and occurrence of temperature inversion in the western seas of Jeju Island in spring. The distribution of water masses was characterized by cold and fresh water in the northwest and warm and saline water in the southeast, forming a strong thermohaline front running in the southwest-to-northeast direction. Strong temperature inversion mainly occurred in the frontal boundary when the cold water intrudes beneath the warm water at depths of 30–50 m. Analysis of the mixing ratio demonstrated that Jeju Warm Water is dominantly distributed in the western seas of Jeju Island, but its ratio can be modified depending on the southward extension of Yellow Sea Cold Water (YSCW). Results of in situ measurement showed that in 2020, the YSCW largely expanded to the western seas of Jeju Island, occupying approximately 40 % of the mixing ratio. Due to the expansion of YSCW, a strong thermohaline front was formed in the study area, thereby causing thick and strong temperature inversion. On the other hand, in 2018 the mixing ratio of YSCW was minimum (~18%) during the study period of 2017–2021, and thus a relatively weak frontal boundary was formed, without the occurrence of temperature inversion. The observational results also suggest that the interannual changes of water mass distribution and the associated temperature inversion in the western seas of Jeju Island are closely related with wind-driven Yellow Sea circulation in spring, which is the summer monsoon transition period.
참고문헌 (31)
- 김성현, "2015년 4월에 제주 서부해역에서 발생한 수온역전층 특성", Ocean and Polar Research, 42(2), pp.97~113 (2020), 한국해양과학기술원[DOI]
- Chu P, "Seasonal variability of the Yellow Sea", East China Sea surface fluxes and thermohaline structure, 2005, pp.22(1), 1~20
- "ERA5 monthly averaged data on single levels from 1959 to present" (2019)[URL]
- 홍지석, "Modeling the Largest Inflow of Changjiang Freshwater into the Yellow Sea in 2012 with Particle-Tracking Experiment", Ocean Science Journal, 51(4), pp.549~562 (2016), 한국해양과학기술원[DOI]
- Hur HB, "Monthly variations of water masses in the Yellow and East China Seas, November 6, 1998", J Oceanogr, 55(2), pp.171~184 (1999)
- Jacobs GA, "Yellow and East China Seas response to winds and currents", J Geophys Res-Oceans, 105(C9), pp.21947~22196 (2000)
- Kang YQ, "On the generation of temperature inversions in the upper layer of the ocean", J Kor Soc Oceanogr, 18(1), pp.43~48 (1983)
- Kim HJ, "Inversion phenomena of density in the Japan Sea", J Kor Soc Oceanogr, 17(2), pp.51~58 (1982)
- Kim K, "Water masses and circulation around Cheju-Do in summer", J Kor Soc Oceanogr, 26(3), pp.262~277 (1991)
- Kondo M, "Oceanographic investigations of fishing current in the East China Sea and the Yellow Sea-1: characteristics of the mean temperature and salinity distributions measured at 50m and near the bottom", Bull Seikai Reg Fish Res Lab, 62, pp.19~66 (1985)
- Lie HJ, "Occurrence of large temperature inversion in the thermohaline frontal zone at the Yellow Sea entrance in winter and its relation to advection", J Geophys Res-Oceans, 120(1), pp.417~435 (2015)
- Lie HJ, "Seasonal variation of the Cheju warm current in the northern East China Sea", J Oceanogr, 56(2), pp.197~211 (2000)
- Lie HJ, "Does the Yellow Sea Warm Current really exist as a persistent mean flow?", J Geophys Res-Oceans, 106(C10), pp.22199~22210 (2001)
- Lie HJ, "Wintertime large temperature inversions in the Yellow Sea associated with the Cheju and Yellow Sea warm currents", J Geophys Res-Oceans, 124(7), pp.4856~4874 (2019)
- Lie HJ, "Summertime hydrographic features in the southeastern Hwanghae", Prog Oceanogr, 17(3–4), pp.229~224 (1986)
- Miller AR, "A study of mixing processes over the edge of the continental shelf", J Mar Res, 9(2), pp.145~160 (1950)
- Moon JH, "Modeling offshore freshwater dispersal from the Changjiang River and controlling factors during summer", Terr Atmos Ocean Sci, 23(3), pp.247~260 (2012)
- Moon JH, "Comparison of wind and tidal contributions to seasonal circulation of the Yellow Sea", J Geophys Res-Oceans, 114(C8), pp.08016~ (2009)[DOI]
- Moon JH, "Contribution of low-salinity water to sea surface warming of the East China Sea in the summer of 2016", Prog Oceanogr, 175, pp.68~80 (2019)
- Moon JH, "Response of the Changjiang diluted water around Jeju Island to external forcings : A modeling study of 2002 and 2006", Cont Shelf Res, 29(13), pp.1549~1564 (2009)
- Nagata Y, "On the structure of shallow temperature inversions", J Oceanogr Soc Japan, 23(5), pp.221~230 (1967)
- Pang IC, "Seasonal variation of water mass distributions in the eastern Yellow Sea and the Yellow Sea warm current", J Kor Soc Oceanogr, 33(3), pp.41~52 (1998)
- Pang IC, "Modeling temperature inversion in southeastern Yellow Sea during winter 2016", J Geophys Res-Oceans, 122(5), pp.3848~ (2017)[DOI]
- Pang IC, "A seasonal circulation in the East China Sea and the Yellow Sea and its possible cause", J Kor Soc Oceanogr, 35(4), pp.161~169 (2000)
- Pang I C, "Seasonal variations of water mass distributions and their causes in the Yellow Sea, the East China Sea and the adjacent seas of Cheju Island", Kor J Fish Aquat Sci, 25(2), pp.151~163 (1992)
- 박경애, "관측 기반 과학적 지식에 근거한 과학교과서 황해 및 동중국해 해류모식도", 바다, 22(4), pp.151~171 (2017), 한국해양학회
- Park S, "Interannual-to-interdecadal variability of the Yellow Sea Cold Water Mass in 1967– 2008 : characteristics and seasonal forcings", J Marine Syst, 87(3–4), pp.177~119 (2011)
- Suk MS, "Observations of the Cheju current", J Kor Soc Oceanogr, 35(3), pp.129~152 (2000)
- Yang HW, "Interannual variation of the southern limit in the Yellow Sea bottom cold water and its causes", J Marine Syst, 139, pp.119~ (2014)[DOI]
- Yang YJ, "Relationship between SST fronts and purse-seine fishing grounds in the South-West Sea of Korea and the northern area of the East China Sea", Kor J Fish Aquat Sci, 32(5), pp.618~623 (1999)
- Zhang SW, "Observation of the seasonal evolution of the Yellow Sea Cold Water Mass in 1996–1998", Cont Shelf Res, 28(3), pp.442~457 (2008)