Semidiurnal Internal Tides Observed on the Eastern Flank of Hanna Shoal in the Northeastern Chukchi Sea DOI Creative Commons
Ying‐Chih Fang, Markus Janout, Yusuke Kawaguchi

et al.

Journal of Geophysical Research Oceans, Journal Year: 2022, Volume and Issue: 127(11)

Published: Oct. 25, 2022

Abstract This paper investigates the role of semidiurnal tides in Hanna Shoal region on northeastern Chukchi Sea shelf to evaluate their impact regional dynamics. The study is based 2‐year long velocity time series from five oceanographic moorings. These records indicate dominance wind‐generated near‐inertial energy during summer season with low ice cover. However, when ocean fully covered by sea ice, dominate variability band. reveal considerable seasonal as well differences, where barotropic well‐mixed waters west while bottom‐trapped internal (depth‐dependent) are observed east Shoal, stratification can persist year‐round. Resulting tide‐driven shear winter under stratified conditions occasionally reach level a Richardson number below 1 and be ∼0.25, implying likelihood instability potentially eroding lower water column stability. may lead upward fluxes near‐bottom nutrient‐rich Winter Water thus carries ecosystem implications. Our indicates that modulated spring‐neap cycle result interaction local bathymetry stratification.

Language: Английский

Subsurface warming associated with Pacific Summer Water transport toward the Chukchi Borderland in the Arctic Ocean DOI Creative Commons

Miaki Muramatsu,

Eiji Watanabe, Motoyo Itoh

et al.

Scientific Reports, Journal Year: 2025, Volume and Issue: 15(1)

Published: Jan. 10, 2025

Recent rapid sea ice reduction in the Pacific sector of Arctic Ocean is potentially associated with inflow Pacific-origin water via Bering Strait. For first time, we detected remarkable subsurface warming around Chukchi Borderland over recent two decades (i.e., early 21st century). A statistically significant decadal trend 16.6 ± 10.6 MJ m− 2 year− 1 ocean heat content during 1999–2020 was captured by shipboard hydrographic data, and transport Summer Water from Barrow Canyon northwest Alaskan coast, where similar appeared. Satellite-derived geostrophic velocity indicated that northwestward current flowing to became faster late 2010s, association southeastward shift Beaufort Gyre, circulating clockwise Canada Basin. Therefore, suggest passing shelf intensification along shelf–basin boundary both acted enhance contributed positive downstream content. Our findings fill important gaps understanding distribution/transport, which a key factor for freezing/melting, central Arctic.

Language: Английский

Citations

1
Floating microplastic inventories in the southern Beaufort Sea, Arctic Ocean DOI Creative Commons
Takahito Ikenoue, R. Nakajima, Pravakar Mishra

et al.

Frontiers in Marine Science, Journal Year: 2023, Volume and Issue: 10

Published: Oct. 12, 2023

The microplastics inflow into the Arctic Ocean may increase environmental stress on marine ecosystem Pacific side, where sea ice has been significantly reduced because of global warming. However, quantitative data are very limited in Beaufort Sea, which is covered by for most year, even summer. We therefore observed microplastic concentrations over a wide area southern Sea using neuston net from 30 August to 10 September 2022 estimate total number (particle inventory) and mass (mass entire water column. particle inventory during sampling period ranged 937 28,081 pieces km −2 (mean ± standard deviation, 7570 7600 ). 22 664 g (179 180 Relatively high inventories (>6500 ) were off Utqiaġvik mouth Mackenzie River, suggesting that some originate not only but also Arctic. These values indicate waters contaminated with same order magnitude as Chukchi Sea.

Language: Английский

Citations

12
Atlantic-origin water extension into the Pacific Arctic induced an anomalous biogeochemical event DOI Creative Commons
Shigeto Nishino, Jinyoung Jung, Kyoung‐Ho Cho

et al.

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Nov. 2, 2023

The Arctic Ocean is facing dramatic environmental and ecosystem changes. In this context, an international multiship survey project was undertaken in 2020 to obtain current baseline data. During the survey, unusually low dissolved oxygen acidified water were found a high-seas fishable area of western (Pacific-side) Ocean. Herein, we show that Beaufort Gyre shrinks east ocean ridge forms front between within gyre from eastern (Atlantic-side) Arctic. That phenomenon triggers frontal northward flow along ridge. This likely transports toward area; similar biogeochemical properties had previously been observed only on shelf-slope north East Siberian Sea.

Language: Английский

Citations

11
Arctic marine environments regulated by ocean transport and air‒sea‒land interaction: Findings from the ArCS II Ocean Research Program DOI
Eiji Watanabe, Hiromichi Ueno, Tsubasa Kodaira

et al.

Polar Science, Journal Year: 2025, Volume and Issue: unknown, P. 101205 - 101205

Published: April 1, 2025

Language: Английский

Citations

0
Changing sources and burial of organic carbon in the Chukchi Sea sediments with retreating sea ice over recent centuries DOI Creative Commons
Liang Su, Jian Ren, Marie‐Alexandrine Sicre

et al.

Climate of the past, Journal Year: 2023, Volume and Issue: 19(7), P. 1305 - 1320

Published: July 5, 2023

Abstract. Decreasing sea ice extent caused by climate change is affecting the carbon cycle of Arctic Ocean. In this study, surface sediments across western Ocean are investigated to characterize sources sedimentary organic (OC). Bulk parameters (total carbon, total nitrogen, δ13Corg, and δ15N) molecular biomarkers (e.g., sterols highly branched isoprenoids – HBIs) combined distinguish between sympagic, pelagic, terrestrial OC sources. Their downcore profiles generated at Chukchi Sea R1 core site (74∘ N) then used evaluate changes in relative contribution these components over last 200 years with decreasing ice. Our data evidence that, from 1820s 1930s, prevailing high cover inhibited situ primary production, resulting prominent land-derived material sediments. Then, 1930s 1980s, production started increasing gradual decline summer The ratio sympagic pelagic began rise account for larger portion OC. Since accelerated loss led enhanced stabilizing decades due freshwater-induced ocean stratification summer.

Language: Английский

Citations

7
Heavy metals and Pb isotopes in sediment cores from the Bering and Chukchi seas: Implications for environmental changes and human activities over the past century DOI
Yan Lin, Zhai Wu, Hongwei Ke

et al.

Marine Environmental Research, Journal Year: 2023, Volume and Issue: 191, P. 106129 - 106129

Published: Aug. 10, 2023

Language: Английский

Citations

5
A resilient ice cover over the southernmost Mendeleev Ridge during the late Quaternary DOI Creative Commons
Tengfei Song, Claude Hillaire‐Marcel, Anne de Vernal

et al.

Boreas, Journal Year: 2023, Volume and Issue: 53(1), P. 106 - 123

Published: Aug. 22, 2023

The presence of a late Quaternary ice sheet/ice shelf over the East Siberian Sea has been proposed in several papers. Here, we further document its duration/resilience based on sedimentary, bulk mineralogical, and geochemical (organic matter content stable isotopic composition, U‐Th series) properties core raised from southernmost Mendeleev Ridge. chronostratigraphy studied was mainly built 230 Th excess ( xs ) distribution decay downcore. At core‐top, peaking values during early MIS 3 mid‐MIS 1 encompassing an 2 hiatus were observed. As documented papers, these peaks suggest seasonally open conditions proximal continental shelves. Below, interval spanning 4 possibly 5d records major ice‐rafting events illustrated by overall high coarse‐fraction contents. Underlying 5e, down to 11, sediment depicts relatively low sand (1.7±2.5 dw%), clay (33.5±4.7 very organic carbon (0.10±0.06 dw%) contents, δ 13 C org (−24.3±0.9‰). This section is interpreted as recording fine transport deep currents and/or meltwater plumes below resilient cover, only interrupted few short‐duration events. These include (i) detrital carbonate pulses assigned deglacial along NW Laurentide Ice Sheet margin (Termination (T) III), (ii) intervals with some planktonic foraminifer occurrences, likely relating their advection areas Arctic Ocean (MIS 9 11). All Terminations, but TII 3, show Mn/Al linked submergence shelves under rising sea level. We conclude that shelf, present southern Ridge most after Mid‐Pleistocene Transition favoured summer insolation 14 10 interval.

Language: Английский

Citations

4
Seasonal variations in the contribution of zooplankton fecal pellets to the particulate organic carbon fluxes over the slopes of the Pacific Arctic region DOI
Jeonghyun Kim, Catherine Lalande, Eun Jin Yang

et al.

Progress In Oceanography, Journal Year: 2024, Volume and Issue: 228, P. 103335 - 103335

Published: Aug. 18, 2024

Language: Английский

Citations

1
Pacific Water impacts the burial of black and total organic carbon on the Chukchi Sea shelf, Arctic Ocean DOI
Yanguang Liu, Peng Ren, Tengfei Song

et al.

Palaeogeography Palaeoclimatology Palaeoecology, Journal Year: 2023, Volume and Issue: 621, P. 111575 - 111575

Published: April 22, 2023

Language: Английский

Citations

2
Changing sources and burial of organic carbon in the Chukchi Sea sediments with retreating sea ice over recent centuries DOI Creative Commons
Liang Su, Jian Ren, Marie‐Alexandrine Sicre

et al.

Published: Jan. 19, 2023

Abstract. Decreasing sea ice extent in summer caused by climate change is affecting the carbon cycle of Arctic Ocean. In this study, surface sediments across western Ocean are investigated to characterize sources sedimentary organic (OC). Bulk parameters (total carbon, total nitrogen, δ13Corg and δ15N) combined with molecular biomarkers (e.g., sterols highly branched isoprenoids (HBIs)) applied distinguish between sympagic, pelagic, terrestrial OC. Furthermore, downcore profiles these were also generated from Chukchi Sea R1 core (74° N) evaluate changes relative contribution three components OC over last 200 years decreasing ice. Our data evidence that 1820s 1930s, prevailing high variable cover inhibited situ primary production resulting prominent land-derived material stored sediments. From 1930s 1980s, gradual decline ice, increased progressively. The ratio sympagic pelagic began rise account for a larger portion Since accelerated loss led enhanced production, stabilizing decades due freshwater induced ocean stratification summer.

Language: Английский

Citations

0