Matches in SemOpenAlex for { <https://semopenalex.org/work/W2588753016> ?p ?o ?g. }
- W2588753016 endingPage "137" @default.
- W2588753016 startingPage "116" @default.
- W2588753016 abstract "Highlights• Multi-proxy, multi-site reconstruction of Okhotsk Sea palaeo-productivity and mid-depth ventilation changes from 8 to 18 ka.• Link between hinterland river discharge and downstream Okhotsk Sea Intermediate Water (OSIW) ventilation/nutrient signatures.• Surplus Fe, Si(OH)4 export in OSIW during Bolling-Allerod to pelagic Pacific supported transient nutrient-replete conditions.• Subarctic and subtropical Pacific gyres disconnected during Bolling-Allerod, with restricted OSIW flow to lower latitudes.• Deglacial OSIW export and mid-depth Pacific biogeochemistry modulate millennial-scale regional CO2 source/sink conditions.The modern North Pacific plays a critical role in marine biogeochemical cycles, as an oceanic sink of CO2 and by bearing some of the most productive and least oxygenated waters of the World Ocean. The capacity to sequester CO2 is limited by efficient nutrient supply to the mixed layer, particularly from deeper water masses in the Pacific's subarctic and marginal seas. The region is in addition only weakly ventilated by North Pacific Intermediate Water (NPIW), which receives its characteristics from Okhotsk Sea Intermediate Water (OSIW). Here, we present reconstructions of intermediate water ventilation and productivity variations in the Okhotsk Sea that cover the last glacial termination between eight and 18 ka, based on a set of high-resolution sediment cores from sites directly downstream of OSIW formation. In a multi-proxy approach, we use total organic carbon (TOC), chlorin, biogenic opal, and CaCO3 concentrations as indicators for biological productivity. C/N ratios and XRF scanning-derived elemental ratios (Si/K and Fe/K), as well as chlorophycean algae counts document changes in Amur freshwater and sediment discharge that condition the OSIW. Stable carbon isotopes of epi- and shallow endobenthic foraminifera, in combination with 14C analyses of benthic and planktic foraminifera imply decreases in OSIW oxygenation during deglacial warm phases from c. 14.7 to 13 ka (Bolling-Allerod) and c. 11.4 to 9 ka (Preboreal). No concomitant decreases in Okhotsk Sea benthic-planktic ventilation ages are observed, in contrast to nearby, but southerly locations on the Japan continental margin. We attribute Okhotsk Sea mid-depth oxygenation decreases in times of enhanced organic matter supply to maxima in remineralization within OSIW, in line with multi-proxy evidence for maxima in primary productivity and supply of organic matter. Sedimentary C/N and Fe/K ratios indicate more effective entrainment of nutrients into OSIW and thus an increased nutrient load of OSIW during deglacial warm periods. Correlation of palynological and sedimentological evidence from our sites with hinterland reference records suggests that millennial-scale changes in OSIW oxygen and nutrient concentrations were largely influenced by fluvial freshwater runoff maxima from the Amur, caused by a deglacial northeastward propagation of the East Asian Summer Monsoon that increased precipitation and temperatures, in conjunction with melting of permafrost in the Amur catchment area. We suggest that OSIW ventilation minima and the high lateral supply of nutrients and organic matter during the Allerod and Preboreal are mechanistically linked to concurrent maxima in nutrient utilization and biological productivity in the subpolar Northwest Pacific. In this scenario, increased export of nutrients from the Okhotsk Sea during deglacial warm phases supported subarctic Pacific shifts from generally Fe-limiting conditions to transient nutrient-replete regimes through enhanced advection of mid-depth nutrient- and Fe-rich OSIW into the upper ocean. This mechanism may have moderated the role of the subarctic Pacific in the deglacial CO2 rise on millennial timescales by combining the upwelling of old carbon-rich waters with a transient delivery of mid-depth-derived bio-available Fe and silicate." @default.
- W2588753016 created "2017-02-24" @default.
- W2588753016 creator A5005945864 @default.
- W2588753016 creator A5024330767 @default.
- W2588753016 creator A5027565564 @default.
- W2588753016 creator A5046267902 @default.
- W2588753016 creator A5050713145 @default.
- W2588753016 creator A5062765817 @default.
- W2588753016 creator A5074027743 @default.
- W2588753016 creator A5083405746 @default.
- W2588753016 date "2017-03-01" @default.
- W2588753016 modified "2023-09-27" @default.
- W2588753016 title "Deglacial variability in Okhotsk Sea Intermediate Water ventilation and biogeochemistry: Implications for North Pacific nutrient supply and productivity" @default.
- W2588753016 cites W1493203841 @default.
- W2588753016 cites W1493465243 @default.
- W2588753016 cites W1501142928 @default.
- W2588753016 cites W1524882152 @default.
- W2588753016 cites W1559133921 @default.
- W2588753016 cites W1562399679 @default.
- W2588753016 cites W1567677637 @default.
- W2588753016 cites W1593116295 @default.
- W2588753016 cites W1608428947 @default.
- W2588753016 cites W1638196061 @default.
- W2588753016 cites W1645629045 @default.
- W2588753016 cites W1658032313 @default.
- W2588753016 cites W1661169959 @default.
- W2588753016 cites W1671613930 @default.
- W2588753016 cites W1752617686 @default.
- W2588753016 cites W1807406143 @default.
- W2588753016 cites W1823070337 @default.
- W2588753016 cites W1832501630 @default.
- W2588753016 cites W1860039907 @default.
- W2588753016 cites W1884540967 @default.
- W2588753016 cites W1963000257 @default.
- W2588753016 cites W1964733269 @default.
- W2588753016 cites W1965607480 @default.
- W2588753016 cites W1968689303 @default.
- W2588753016 cites W1971816180 @default.
- W2588753016 cites W1972212714 @default.
- W2588753016 cites W1972256856 @default.
- W2588753016 cites W1972259038 @default.
- W2588753016 cites W1972533998 @default.
- W2588753016 cites W1974230057 @default.
- W2588753016 cites W1974830812 @default.
- W2588753016 cites W1974971410 @default.
- W2588753016 cites W1975498061 @default.
- W2588753016 cites W1981018595 @default.
- W2588753016 cites W1982886400 @default.
- W2588753016 cites W1983087121 @default.
- W2588753016 cites W1983680051 @default.
- W2588753016 cites W1988124533 @default.
- W2588753016 cites W1989974710 @default.
- W2588753016 cites W1990726956 @default.
- W2588753016 cites W1991549432 @default.
- W2588753016 cites W1993234708 @default.
- W2588753016 cites W1993690476 @default.
- W2588753016 cites W1994007098 @default.
- W2588753016 cites W1996932107 @default.
- W2588753016 cites W1998818093 @default.
- W2588753016 cites W1999779483 @default.
- W2588753016 cites W2001261279 @default.
- W2588753016 cites W2001527610 @default.
- W2588753016 cites W2002717773 @default.
- W2588753016 cites W2007987130 @default.
- W2588753016 cites W2009429119 @default.
- W2588753016 cites W2009814424 @default.
- W2588753016 cites W2013836518 @default.
- W2588753016 cites W2013900698 @default.
- W2588753016 cites W2014727327 @default.
- W2588753016 cites W2016105826 @default.
- W2588753016 cites W2020143786 @default.
- W2588753016 cites W2021844606 @default.
- W2588753016 cites W2022169992 @default.
- W2588753016 cites W2022626025 @default.
- W2588753016 cites W2027385173 @default.
- W2588753016 cites W2030003797 @default.
- W2588753016 cites W2031108741 @default.
- W2588753016 cites W2034453848 @default.
- W2588753016 cites W2035180843 @default.
- W2588753016 cites W2039691001 @default.
- W2588753016 cites W2040188259 @default.
- W2588753016 cites W2042088181 @default.
- W2588753016 cites W2043452910 @default.
- W2588753016 cites W2046432746 @default.
- W2588753016 cites W2048742978 @default.
- W2588753016 cites W2050331739 @default.
- W2588753016 cites W2050992812 @default.
- W2588753016 cites W2051461957 @default.
- W2588753016 cites W2057037894 @default.
- W2588753016 cites W2058478319 @default.
- W2588753016 cites W2059173245 @default.
- W2588753016 cites W2059849751 @default.
- W2588753016 cites W2062312345 @default.
- W2588753016 cites W2062683518 @default.
- W2588753016 cites W2063534846 @default.
- W2588753016 cites W2063825722 @default.
- W2588753016 cites W2064728385 @default.
- W2588753016 cites W2064832016 @default.