A tracer study of ventilation in the Japan/East Sea

Postlethwaite, C. F.; Rohling, Eelco J.; Jenkins, William J.; Walker, Caleb

doi:10.1016/j.dsr2.2004.07.032

Cited by 44 publications

(49 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The cessation of deep water formation was replaced with the sinking of surface waters to shallower depth levels (Postlewaite et al, 2005;Jenkins, 2008). The present study suggests the springtime advection of the ESIW influences the subsurface spring bloom in the UB together with other factors previously suggested.…”

Section: Discussionmentioning

confidence: 54%

A newly observed physical cause of the onset of the subsurface spring phytoplankton bloom in the southwestern East Sea/Sea of Japan

et al. 2014

View full text Add to dashboard Cite

Abstract. An ocean buoy, UBIM (Ulleung Basin Integrated Mooring), deployed during the spring transition from February to May 2010 reveals for the first time highly resolved temporal variation of biochemical properties of the upper layer of the Ulleung Basin in the southwestern East Sea/Sea of Japan. The time-series measurement captured the onset of subsurface spring bloom at 30 m, and collocated temperature and current data gives an insight into a mechanism that triggers the onset of the spring bloom not documented so far. Low-frequency modulation of the mixed layer depth ranging from 10 m to 53 m during the entire mooring period is mainly determined by shoaling and deepening of isothermal depths depending on the placement of UBIM on the cold or warm side of the frontal jet. The occurrence of the spring bloom at 30 m is concomitant with the appearance of colder East Sea Intermediate Water at buoy UBIM, which results in subsurface cooling and shoaling of isotherms to the shallower depth levels during the bloom period than those that occurred during the pre-bloom period. Isolines of temperature-based NO 3 are also shown to be uplifted during the bloom period. It is suggested that the springtime spreading of the East Sea Intermediate Water is one of the important factors that triggers the subsurface spring bloom below the mixed layer.

show abstract

Section: Discussionmentioning

confidence: 54%

A newly observed physical cause of the onset of the subsurface spring phytoplankton bloom in the southwestern East Sea/Sea of Japan

et al. 2014

View full text Add to dashboard Cite

show abstract

“…Based on published data (Ki 1999, Postlethwaite et al 2005, water δ 18 O SMOW = 0.2 ‰ was used for lots P1 to P7, J1, and J2, and water δ 18 O SMOW = -0.4 ‰ was used for lots J3 and J4 in the calculation (see 'Discussion'). …”

Section: Methodsmentioning

confidence: 99%

“…In the southern Japan Sea where tuna of lot J1 were collected, the sea surface water δ 18 O SMOW value varies between 0.02 and 0.22 ‰ (as shown in Fig. 2 of Postlethwaite et al 2005). Based on the literature data, tuna of lots P1 to P7, J1, and J2 should experience a similar water C values from beyond 800 to 1000 μm from the core.…”

Section: Present Study) the First Winter Signal Recorded In Otmentioning

confidence: 99%

Natal origin of Pacific bluefin tuna Thunnus orientalis inferred from otolith oxygen isotope composition

Shiao

Wang²,

Yokawa³

et al. 2010

Mar. Ecol. Prog. Ser.

View full text Add to dashboard Cite

“…Various chemical tracers have been used: radium-226 (Harada and Tsunogai, 1986), tritium (Watanabe et al, 1991;Postlethwaite et al, 2005), chlo-rofluorocarbons (Tsunogai et al, 1993;Riser et al, 1999), rare earth elements (Hatta and Zhang, 2006), and iodine-129 (Suzuki et al, 2009a, b), as well as carbon-14 (Chen et al, 1995;Kumamoto et al, 1998Kumamoto et al, , 2008. Many of the studies gave a timescale of 100-200 years, slightly shorter than the 300 ± 100 years reported by Gamo and Horibe (1983).…”

Section: Water Mass Structure and Timescale Of Abyssal Circulationmentioning

confidence: 99%

“…Some helium isotope data were obtained in 1986 from a station in the Eastern Japan Basin (Sano et al, 1989), in 1999 from the entire region of the Japan Sea (Postlethwaite et al, 2005), and in 2005 from the Eastern Japan Basin and the Yamato Basin (Takahata et al, 2008). Based on these data, the helium isotopes in the Japan Sea are characterized as follows: (1) maximum δ 3 He values of ∼8% (Postlethwaite et al, 2005;Takahata et al, 2008) are observed at mid-depth (∼1000 m), which may be attributable to the decay product of the bomb-produced tritium, (2) δ 3 He values in deep waters are significantly smaller than those in deep Pacific waters (at 2500 m depth) ∼20% adjacent to the Japanese archipelago, which indicates that mantle-derived helium in deep Pacific seawater cannot enter the Japan Sea, and (3) the homogeneous δ 3 He values of ∼2% observed in bottom waters (Postlethwaite et al, 2005;Takahata et al, 2008) indicate that very little mantle helium is supplied from the bottom (Fig. 14).…”

Section: Helium Isotopesmentioning

confidence: 99%

The Sea of Japan and Its Unique Chemistry Revealed by Time-Series Observations over the Last 30 Years

Gamo¹,

Nakayama²,

Takahata³

et al. 2014

Monogr. Environ. Earth Planets

View full text Add to dashboard Cite

Chemical tracers in seawater, as well as physical parameters such as temperature and salinity, have been measured to better characterize the dynamics of water convection and its spatiotemporal changes in the Sea of Japan (also called the Japan Sea), a semi-closed, hyperoxic marginal sea (maximum depth: ∼3,800 m) in the northwestern corner of the Pacific Ocean. Repeated conductivity, temperature, and depth (CTD) observations and measurements of dissolved oxygen, for more than 30 years, have confirmed that the bottom layer of the Japan Sea, with a thickness of ∼1 km below the boundary at a depth of ∼2,500 m, is characterized by vertical homogeneity with fluctuations of potential temperature and dissolved oxygen of <0.001• C and <0.5 µmol kg −1 , respectively. The timescale of the abyssal circulation in the Japan Sea has been estimated to be 100-300 years, using 14 C and other chemical tracers. Stable isotope analyses for dissolved He, O 2 and CH 4 have given us information on their unique geochemical cycles in the Japan Sea. Profiles of the short-lived radioisotope 222 Rn just above the sea bottom have brought new insights into the short-term lateral water movement with a timescale of several days in the Japan Sea bottom water. It is of special concern that the gradual deoxygenation and warming of the bottom water over the last 30 years have resulted in an ∼10% decrease in dissolved oxygen and ∼0.04• C increase in potential temperature, suggesting a change of the deep convection system in the Japan Sea. The temporal changes in the vertical profiles of tritium from 1984 to 1998 have suggested a shift of the abyssal circulation pattern from a "total (overall) convection mode" to a "shallow (partial) convection mode". It is likely that the global warming since the last century has hindered the formation of dense surface seawater and its ability to sink down to the bottom, isolating the bottom layer from the deep convection loop that is indispensable as the source of cold and oxygen-rich water. However, the decreasing trend of bottom dissolved oxygen between 1977 and 2010 was not monotonous; rather, it was interrupted by an occasional break in the winter of 2000-2001, when severely cold weather may have resulted in especially dense surface water to sink down to the bottom layer for its ventilation.

show abstract

A tracer study of ventilation in the Japan/East Sea

Cited by 44 publications

References 36 publications

A newly observed physical cause of the onset of the subsurface spring phytoplankton bloom in the southwestern East Sea/Sea of Japan

A newly observed physical cause of the onset of the subsurface spring phytoplankton bloom in the southwestern East Sea/Sea of Japan

Natal origin of Pacific bluefin tuna Thunnus orientalis inferred from otolith oxygen isotope composition

The Sea of Japan and Its Unique Chemistry Revealed by Time-Series Observations over the Last 30 Years

Contact Info

Product

Resources

About