TY - JOUR
T1 - Characteristics of the East Sea (Japan Sea) circulation depending on surface heat flux and its effect on branching of the Tsushima Warm Current
AU - Kim, Daehyuk
AU - Shin, Hong Ryeol
AU - Kim, Cheol Ho
AU - Hirose, Naoki
N1 - Funding Information:
This work was supported by the project entitled “ A Study on Ocean Reanalysis Data Production in the North Pacific and Marginal Seas Around Korea , 3 rd ( GPRN : 11-1192136-000395-01 )” from the Korea Hydrographic and Oceanographic Agency (KHOA) , and a part of the project titled “Study on Air-Sea interaction and Process of Rapidly Intensifying Typhoon in the Northwestern Pacific”, funded by the Ministry of Oceans and Fisheries, Korea . Numerical model simulations using supercomputer provided by the KHOA were made possible with grant. In addition, the authors are grateful to the National Institute of Fisheries Science (NIFS) for providing observation data.
Funding Information:
This work was supported by the project entitled ?A Study on Ocean Reanalysis Data Production in the North Pacific and Marginal Seas Around Korea, 3rd (GPRN: 11-1192136-000395-01)? from the Korea Hydrographic and Oceanographic Agency (KHOA), and a part of the project titled ?Study on Air-Sea interaction and Process of Rapidly Intensifying Typhoon in the Northwestern Pacific?, funded by the Ministry of Oceans and Fisheries, Korea. Numerical model simulations using supercomputer provided by the KHOA were made possible with grant. In addition, the authors are grateful to the National Institute of Fisheries Science (NIFS) for providing observation data.
PY - 2020/1/1
Y1 - 2020/1/1
N2 - The effects of the surface heat flux and wind forcing on the East Sea (Japan Sea) circulation and the branching of the Tsushima Warm Current were investigated using a three-dimensional circulation model (RIAMOM). For the numerical experiments with surface heat flux, regardless of wind forcing, the Tsushima Warm Current, the Nearshore Branch, and the East Korea Warm Current were well simulated in the southern part of the East Sea. Furthermore, the cold water mass of 1–2 °C was formed at a depth of 200–250 m because of the convection of the upper layer and ventilation that actively occurs in the northern part of the East Sea. However, in the experiments without surface heat flux, the East Korea Warm Current was not simulated. The Tsushima Warm Current through the Korea/Tsushima Strait flows mostly northeastward along the Japanese coast as the Nearshore Branch. Moreover, the cold water mass was not formed at the northern part of the East Sea, thus the 1–2 °C cold water was distributed below 300–400 m depth with weak ventilation. The upper layer in the southern part of the East Sea, ranging from the surface to the bottom of the pycnocline, was thicker than the case of the surface heat flux forcing. Since the Tsushima Warm Current flowing through the Korea/Tsushima Strait is dominantly affected by the continental slope of the Japanese coast, the current does not lead to formation of the East Korea Warm Current as a western boundary current. If the effect of the continental slope of the Japanese coast is not applied, the Tsushima Warm Current flows only along the Korean coast as a western boundary current. The numerical experiments reveal that the surface heat flux serves as a critical external forcing which controls the topographic and planetary beta effects on the upper layer circulation in the southern part of the East Sea. Therefore, if the surface heat flux is changed due to global warming in the future, the distribution of surface currents is also expected to change in the southern part of the East Sea.
AB - The effects of the surface heat flux and wind forcing on the East Sea (Japan Sea) circulation and the branching of the Tsushima Warm Current were investigated using a three-dimensional circulation model (RIAMOM). For the numerical experiments with surface heat flux, regardless of wind forcing, the Tsushima Warm Current, the Nearshore Branch, and the East Korea Warm Current were well simulated in the southern part of the East Sea. Furthermore, the cold water mass of 1–2 °C was formed at a depth of 200–250 m because of the convection of the upper layer and ventilation that actively occurs in the northern part of the East Sea. However, in the experiments without surface heat flux, the East Korea Warm Current was not simulated. The Tsushima Warm Current through the Korea/Tsushima Strait flows mostly northeastward along the Japanese coast as the Nearshore Branch. Moreover, the cold water mass was not formed at the northern part of the East Sea, thus the 1–2 °C cold water was distributed below 300–400 m depth with weak ventilation. The upper layer in the southern part of the East Sea, ranging from the surface to the bottom of the pycnocline, was thicker than the case of the surface heat flux forcing. Since the Tsushima Warm Current flowing through the Korea/Tsushima Strait is dominantly affected by the continental slope of the Japanese coast, the current does not lead to formation of the East Korea Warm Current as a western boundary current. If the effect of the continental slope of the Japanese coast is not applied, the Tsushima Warm Current flows only along the Korean coast as a western boundary current. The numerical experiments reveal that the surface heat flux serves as a critical external forcing which controls the topographic and planetary beta effects on the upper layer circulation in the southern part of the East Sea. Therefore, if the surface heat flux is changed due to global warming in the future, the distribution of surface currents is also expected to change in the southern part of the East Sea.
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U2 - 10.1016/j.csr.2019.104025
DO - 10.1016/j.csr.2019.104025
M3 - Article
AN - SCOPUS:85076085937
VL - 192
JO - Continental Shelf Research
JF - Continental Shelf Research
SN - 0278-4343
M1 - 104025
ER -