Deep-sea Research Part Ii-topical Studies in Oceanography最新文献_第2页

Understanding future changes of Chlorophyll-a in the Indian Ocean using CMIP6 Earth System Model simulations

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-sea Research Part Ii-topical Studies in Oceanography

Pub Date : 2025-01-12 DOI: 10.1016/j.dsr2.2025.105458

Athira K. , Prasanna Kanti Ghoshal , A.P. Joshi , Linta Rose , Kunal Chakraborty

This study uses the Coupled Model Intercomparison Project phase 6 (CMIP6) Earth System Model simulated outputs and satellite-based chlorophyll-a (Chl-a) observations to understand the changes in Chl-a concentration in the recent past and its future changes in the Indian Ocean. Based on the availability of common models across the three future scenarios (SSP5-8.5, SSP2-4.5, and SSP1-2.6), we chose 11 CMIP6 models for this study. The climatology of these model-simulated historical outputs is assessed against a satellite-based Ocean Colour Climate Change Initiative-Version 5 (OC-CCI-V5) data product. The Indian Ocean (IO) is divided into four regions (Arabian Sea (AS), Bay of Bengal (BoB), Central Indian Ocean (CIO), and Southern Indian Ocean (SIO)), and the performance of each of these CMIP6 models are evaluated in each of these regions of IO. Based on the statistical analysis, GFDL-ESM4 is found to be the best-performing model across all four IO regions. However, the GFDL-ESM4 underestimates Chl-a concentration in the AS and CIO regions (

>

0.07 mg/m

^{3}

), whereas it overestimates Chl-a concentration in the BoB region (

<

−0.07 mg/m

^{3}

). The GFDL-ESM4 performs relatively better in the SIO region with a less biased Chl-a concentration. Under the SSP5-8.5 scenario, the future changes of Chl-a indicate a large decrease in the Chl-a concentrations (

<

−0.04 mg/m

^{3}

) in the western coast of the AS, the western coast of BoB, and the southern Java coast. This large decrease in Chl-a concentration is limited to nearly 0.01 mg/m

^{3}

under the SSP1-2.6 scenario. Therefore, the implementation of extreme mitigation measures can control the reduction of surface Chl-a concentration in the IO. The analysis to understand future changes in Chl-a concentration in the mixed layer of six upwelling zones in the IO indicates a decrease in Chl-a concentration in the mixed layer by −0.06 to −0.09 mg/m

^{3}

in all future scenarios.

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引用次数: 0

Late Holocene and recent cold-water coral calcium carbonate production in Guilvinec Canyon, Bay of Biscay, France

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-sea Research Part Ii-topical Studies in Oceanography

Pub Date : 2024-12-29 DOI: 10.1016/j.dsr2.2024.105451

Evan Edinger , Jean-François Bourillet , Lenaïck Menot , Franck Lartaud , Mathilde Chemel , Stephan Jorry

Cold-water coral reefs and communities can be locally important calcium carbonate factories in continental shelf and slope environments, including submarine canyons. Here we present short-term and long-term estimates of coral carbonate production by colonial scleractinian coral communities in the 750–850 m depth range in Guilvinec Canyon, northern Bay of Biscay. Short-term (annual-decadal) estimates were calculated using local coral skeletal biomass, estimated as a product of coral size and abundance from ROV video surveys, a locally generated species-specific regression between coral colony size and wet weight, and published daily or annual percent growth rates for Lophelia pertusa and Madrepora oculata. A long-term (century-millennial) estimate of carbonate accretion for the same reef was derived from a piston core through the same coral community.

Average live colonial scleractinian skeletal biomass in the Guilvinec Canyon coral mounds was 153.9 ± 39.4 g CaCO₃ m⁻². Applying published growth rates, the average annual gross carbonate production was 6.85 ± 1.79 g CaCO₃ m⁻² y⁻¹, range 0–30.2 g CaCO₃ m⁻² y⁻¹. This carbonate production rate was about one order of magnitude lower than previous estimates from the Norwegian shelf.

A 2011 piston core through the mound was analyzed by CT-scan and subsampled for coral abundance. An age model from previous ¹⁴C and U/Th ages of coral fragments in the core yielded a long-term average coral carbonate accretion rate of 78 g CaCO₃ m⁻² y⁻¹ over the past ∼2150 y, range 40.8 (core-bottom) to 148.5 g CaCO₃ m⁻² y⁻¹ in the upper half, about 1–2 orders of magnitude lower than previous estimates from other regions.

Low carbonate accretion rates observed in the Guilvinec Canyon mounds could be attributable to recent declines in live coral cover, indicated by low abundance of live corals in ROV surveys from this site, compared to other regions of the Northeast Atlantic.

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引用次数: 0

Unveiling marine heatwave dynamics in the Persian /Arabian Gulf and the Gulf of Oman: A spatio-temporal analysis and future projections 揭示波斯湾/阿拉伯湾和阿曼湾的海洋热浪动态：时空分析和未来预测

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-sea Research Part Ii-topical Studies in Oceanography

Pub Date : 2024-11-08 DOI: 10.1016/j.dsr2.2024.105435

Mohamed Shaltout , Ahmed Eladawy

Amid escalating global marine heat waves, the Arabian Gulf is critical due to its shallow depths, high temperatures, and vulnerability to climate change impacts. This study provides a detailed spatio-temporal analysis of marine heatwave events from 1982 to 2022 across the Arabian Gulf and the adjacent Gulf of Oman. The study delineates regions of heightened vulnerability within these water bodies by comprehensively analyzing seasonal and annual variabilities and trend assessments. Moreover, an exploration of prevailing surface circulation patterns, underpinned by an extensive study of global circulation model outputs, elucidates the oceanographic mechanisms contributing to temperature dynamics. Identifying 25 significant heat wave events, with a focused examination of the six most protracted episodes, is noteworthy among the findings. Strikingly, the analysis reveals that the Gulf of Oman surpasses the Arabian Gulf in heatwave intensity. Looking forward, the investigation extends to future surface water temperature projections up to the close of the current century. The collective results underscore the region's acute susceptibility to the climate change perturbations of climate change, emphasizing the urgency of targeted interventions to mitigate these effects and address concurrent local stressors.

在全球海洋热浪不断升级的情况下，阿拉伯湾因其水深较浅、温度较高以及易受气候变化影响而显得至关重要。本研究对 1982 年至 2022 年阿拉伯湾和邻近的阿曼湾的海洋热浪事件进行了详细的时空分析。该研究通过全面分析季节和年度变化及趋势评估，划定了这些水体中易受影响的区域。此外，在对全球环流模型输出进行广泛研究的基础上，还对当前的海面环流模式进行了探讨，从而阐明了导致温度动态变化的海洋学机制。研究结果中值得注意的是确定了 25 次重大热浪事件，并重点研究了 6 次持续时间最长的热浪事件。引人注目的是，分析表明阿曼湾的热浪强度超过了阿拉伯湾。展望未来，调查将延伸至本世纪末的未来地表水温度预测。这些综合结果突出表明，该地区极易受到气候变化的干扰，强调迫切需要采取有针对性的干预措施，以减轻这些影响并解决当地同时存在的压力因素。

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引用次数: 0

Ecophenotypic variation in a cosmopolitan reef-building coral suggests reduced deep-sea reef growth under ocean change 一种世界性造礁珊瑚的生态表型变异表明，海洋变化导致深海珊瑚礁生长减少

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-sea Research Part Ii-topical Studies in Oceanography

Pub Date : 2024-11-01 DOI: 10.1016/j.dsr2.2024.105434

Giovanni Sanna , André Freiwald

Sensitivity of reef-building corals to environmental factors has far-reaching ecosystem implications, especially in the limited number of cold-water coral (CWC) species that form reefs in the deep sea. Understanding CWC responses to large-scale oceanographic variation in their natural habitat can elucidate their sensitivity to global anthropogenic stressors. Here, we use skeletal samples to analyse fine-scale phenotypic variation in the widespread reef-building CWC Desmophyllum pertusum (Lophelia pertusa) in relation to broad physicochemical gradients in different sites across the Atlantic Ocean and Mediterranean Sea. We find evidence, amidst local and regional differentiation, of species-wide growth responses to physicochemical factors, mainly affecting corallite length, width and their ratio (slenderness). Our results suggest that higher temperature and lower oxygen levels negatively affect skeletal linear extension and budding rate of polyps. As also hinted by the reduced corallite length and slenderness in less developed reefs, these widespread responses may lead to a general decline in CWC reef growth rates as a long-term consequence of ocean warming and deoxygenation. Given this relevance, such responses can be used to model reef growth in a changing ocean.

造礁珊瑚对环境因素的敏感性对生态系统有着深远的影响，尤其是在深海中形成珊瑚礁的数量有限的冷水珊瑚（CWC）物种。了解冷水珊瑚在其自然栖息地对大规模海洋变化的反应，可以阐明它们对全球人为压力因素的敏感性。在这里，我们利用骨骼样本分析了大西洋和地中海不同地点广泛分布的造礁珊瑚Desmophyllum pertusum（Lophelia pertusa）与广泛的物理化学梯度相关的细尺度表型变异。我们发现，在局部和区域差异中，有证据表明整个物种的生长对理化因素的反应，主要影响珊瑚虫的长度、宽度及其比率（纤度）。我们的研究结果表明，较高的温度和较低的氧气水平会对珊瑚虫的骨骼线性延伸和出芽率产生负面影响。正如欠发达珊瑚礁的珊瑚虫长度和细长度减少所暗示的那样，这些普遍反应可能会导致珊瑚礁生长率的普遍下降，这是海洋变暖和脱氧的长期后果。鉴于这种相关性，这些反应可用于模拟变化海洋中的珊瑚礁生长。

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引用次数: 0

Siliceous microfossil assemblages in the southern Emperor Seamount Chain sediments and their biogeographical and paleoceanographical implications 皇帝海山链南部沉积物中的硅质微化石组合及其生物地理学和古海洋学意义

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-sea Research Part Ii-topical Studies in Oceanography

Pub Date : 2024-10-22 DOI: 10.1016/j.dsr2.2024.105433

Lidiya N. Vasilenko , Ira B. Tsoy , Tatyana N. Dautova

The taxonomic composition and abundance of siliceous microfossils in sediments is a valuable source of information about environmental changes at the sea surface today and in the geological past. This paper presents the results of a study of siliceous microplankton (radiolaria, diatoms, and silicoflagellates) in the surface calcareous sediments (silty foraminiferal oozes and sands) of the Nintoku, Jingu, Ojin, Koko, and Yuryaku guyots at the southern end of the Emperor Seamount Chain (ESC). Bottom sediments were collected using an underwater remote-operated vehicle (ROV) Comanche-18. The study revealed the taxonomic diversity and relatively high abundance of siliceous microplankton. Radiolarians are represented by 237 taxa (104 taxa from 68 genera of Spumellaria, 120 taxa from 61 genera of Nassellaria, and 13 taxa from 7 genera of Collodaria). Diatoms are represented by 60 species from 29 genera, and silicoflagellates by 5 species from 3 genera. Differences in siliceous microplankton reflect the northern boundary of warm water in the ESC, passing at approximately 38°N, between the Jingu and Ojin guyots, which coincides with the boundary of the Kuroshio Bifurcation Current, confirmed by the corals and the bathyal fauna of brittle stars (Ophiura). The absence of remains of siliceous microplankton in some sediments is probably due to dissolution, and the presence of extinct taxa from older sedimentary rocks and neritic species is due to process of reworking caused by active hydrodynamics on ESC guyots and transport by currents.

沉积物中硅质微化石的分类组成和丰度是了解当今和过去地质年代海面环境变化的宝贵信息来源。本文介绍了对位于帝王海山链（ESC）南端的仁德、神宫、大神、芋头和汤乐海沟表层钙质沉积物（淤泥状有孔虫渗出物和泥沙）中硅质微浮游生物（放射虫、硅藻和硅鞭毛虫）的研究结果。使用水下遥控潜水器（ROV）Comanche-18 采集了海底沉积物。研究显示了硅质微浮游生物的分类多样性和相对较高的丰度。放射虫有 237 个类群（104 个类群来自 Spumellaria 的 68 个属，120 个类群来自 Nassellaria 的 61 个属，13 个类群来自 Collodaria 的 7 个属）。硅藻有 29 属 60 种，硅鞭毛虫有 3 属 5 种。硅质微浮游生物的差异反映了在神宫和大神之间约北纬 38 度处的 ESC 暖水北部边界，该边界与黑潮分叉流的边界相吻合，珊瑚和脆星（Ophiura）的水深动物群证实了这一点。一些沉积物中没有硅质微型浮游生物的残骸可能是由于溶解造成的，而较古老沉积岩中已灭绝的类群和海生物种的出现则是由于 ESC 盖奥特上活跃的水动力和海流的输送造成的再加工过程。

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引用次数: 0

The first Mud Dragons (Kinorhyncha) from the Emperor Seamount Chain (Northwestern Pacific) with notes on their biogeography and distribution patterns in the Pacific Deep-Sea 来自皇帝海山链（西北太平洋）的第一条泥龙（Kinorhyncha），以及关于其生物地理学和太平洋深海分布模式的说明

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-sea Research Part Ii-topical Studies in Oceanography

Pub Date : 2024-10-18 DOI: 10.1016/j.dsr2.2024.105430

Andrey V. Adrianov , Anastassya S. Maiorova

Seamounts and oceanic currents play crucial roles in shaping the genetic diversity of species by either acting as barriers or pathways for species dispersal. In the meiofaunal samples collected using ROV facilities at the slope of the Koko Guyot (2172 m) in the southernmost part of the Emperor Seamount Chain in the Northwestern Pacific, we found representatives of three kinorhynch genera, Echinoderes cf. lupherorum Sørensen et al. 2018, Campyloderes cf. vanhoeffeni Zelinka, 1913 and Sphenoderes sp. 1., previously known from other locations in the Pacific. Kinorhynchs were studied and illustrated using light (LM) and scanning electron (SEM) microscopy to prove the species identity and to compare morphological variations with representatives of these species collected from other, very distant localities in the Pacific. We illustrate the pan-oceanic distribution of the collected species with a system of abyssal currents in the Pacific. The probable distribution pattern corresponds with the northward pathway of Antarctic Bottom Water out of the Southern Ocean in the Pacific through the deep-sea area off New Zealand. Echinoderes lupherorum appears to be the first representative of the Echinoderidae with the pan-Pacific distribution. Discussions on the biogeography of Campyloderes cf. vanhoeffeni Zelinka, 1913 and Sphenoderes in the Pacific are also provided.

海山和洋流是物种扩散的障碍或途径，在形成物种遗传多样性方面发挥着至关重要的作用。在西北太平洋皇帝海山链最南端的科科古约特（Koko Guyot，海拔 2172 米）斜坡上使用遥控潜水器采集的小型底栖生物样本中，我们发现了之前在太平洋其他地点已知的三个鞘翅目属的代表，即 Echinoderes cf. lupherorum Sørensen et al.使用光学显微镜（LM）和扫描电子显微镜（SEM）研究并展示了 Kinorhynchs，以证明其物种特征，并将其形态变化与从太平洋其他非常遥远的地点采集的这些物种的代表进行比较。我们用太平洋深海洋流系统说明了所采集物种的泛洋分布。可能的分布模式与南极底层水从太平洋南大洋向北流经新西兰附近深海区域的路径一致。Echinoderes lupherorum 似乎是棘皮动物科中第一个泛太平洋分布的代表。此外，还讨论了 Campyloderes cf. vanhoeffeni Zelinka, 1913 和 Sphenoderes 在太平洋的生物地理学。

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引用次数: 0

Latitudinal variation in zooplankton over the Emperor Seamounts (34°–44° N, 170°–171° E) during the summer of 2019 2019 年夏季皇帝海山（北纬 34°-44°，东经 170°-171°）浮游动物的纬度变化

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-sea Research Part Ii-topical Studies in Oceanography

Pub Date : 2024-10-18 DOI: 10.1016/j.dsr2.2024.105432

Valentina V. Kasyan

The horizontal and vertical distributions of zooplankton over the Emperor Seamounts (Koko, Jingu, Nintoku, and Suiko guyots) were analyzed. The zooplankton was represented by four genera of amphipods, seven genera of pteropods, 39 genera of copepods, and larvae of benthic invertebrates and fish. The abundance and biomass of zooplankton increased towards higher latitudes along the series Koko < Jingu < Nintoku < Suiko guyots. The highest index of diversity was recorded over the Koko and Jingu guyots; the highest species richness occurred over the Jingu and Nintoku guyots. Small-sized copepods, appendicularians, chaetognaths, euphausiids, and fish eggs and larvae concentrated in the epipelagic; large copepods and ostracods were concentrated in the mesopelagic. We identified three types of zooplankton assemblages: a Subtropical assemblage between 34°–35°N characterized by tropical/subtropical forms; a Transition assemblage characterized by subtropical, subarctic, and widespread species between 38°–41°N; and a Subarctic assemblage characterized by subarctic and widespread species between 43°–44°N. The spatial distribution of zooplankton was a function of environmental variables such as surface salinity, temperature at 200 m, and, to a certain extent, by surface Chl-a concentrations.

分析了帝王海山（国角海山、神宫海山、仁德海山和须伊科海山）浮游动物的水平和垂直分布情况。浮游动物包括 4 属片足类、7 属翼足类、39 属桡足类以及底栖无脊椎动物和鱼类的幼虫。浮游动物的丰度和生物量沿 Koko < Jingu < Nintoku < Suiko guyots 系列向高纬度方向增加。Koko 和 Jingu 盖奥茨的多样性指数最高；Jingu 和 Nintoku 盖奥茨的物种丰富度最高。小型桡足类、阑尾类、糠虾类、裙带菜类、鱼卵和幼虫集中在上深海；大型桡足类和梭形纲动物集中在中深海。我们确定了三种浮游动物群落：北纬 34°-35° 之间的亚热带群落，以热带/亚热带形式为特征；北纬 38°-41° 之间的过渡群落，以亚热带、亚北极和广布物种为特征；北纬 43°-44° 之间的亚北极群落，以亚北极和广布物种为特征。浮游动物的空间分布受环境变量的影响，如表层盐度和 200 米处的温度，并在一定程度上受表层 Chl-a 浓度的影响。

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引用次数: 0

Methane distribution above the Emperor Seamount chain 皇帝海山链上方的甲烷分布情况

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-sea Research Part Ii-topical Studies in Oceanography

Pub Date : 2024-10-16 DOI: 10.1016/j.dsr2.2024.105431

Nikita S. Polonik, Alexey A. Legkodimov

Dissolved methane (CH₄) concentrations were measured in the water column at 25 stations along the four sections above Koko and Jingu guyots (the southern part of Emperor Seamount chain). The measured methane concentrations were relatively low (1–6.5 nM). The patterns of CH₄ vertical distributions over Koko and Jingu were different. The greatest dissolved methane concentrations (6.5 nM) were found in the near-bottom layer (357 m) above the Koko summit. For Koko guyot, the greatest CH₄ content (3.9–6.5 nM) was mainly associated with the subsurface (10–300 m) layer above the summit. However, another methane plume (6 nM) was detected at 1000 m on the western slope of the guyot. We propose that methane maximum was caused by the influence of the Kuroshio Extension or deep eddies. The CH₄ distribution over Jingu gyuot was similar to that in open ocean waters. The greatest methane concentrations (3.8–6 nM) were found in the subsurface layers above the summit. Methane exceeded atmospheric equilibrium concentration in the surface (5–52 % supersaturation) layer for both Koko and Jingu. The methane content and supersaturation level in the subsurface layer was at least two times higher than previously measured values for the open ocean. We believe that the high methane and supersaturation level was caused by enhanced methanogenesis in the water column above the seamounts. The estimated methane flux to the atmosphere varied from 1.4 to 16.3 μmol m⁻² day⁻¹ for Koko and from 0.5 to 6.5 μmol m⁻² day⁻¹ for Jingu, respectively. The average fluxes calculated for Koko (8.37 μmol m⁻² day⁻¹) and Jingu (2.8 μmol m⁻² day⁻¹) were significantly greater than the average flux for open and coastal oceans. Given the substantial methane atmospheric contributions, the global methane budget should be reconsidered.

在 Koko 和 Jingu guyots（帝王海山链南部）上方四个断面的 25 个站点测量了水体中的溶解甲烷（CH4）浓度。测得的甲烷浓度相对较低（1-6.5 nM）。科科和神宫上空的甲烷垂直分布模式不同。最大的溶解甲烷浓度（6.5 nM）出现在科科山顶上方的近底层（357 米）。在 Koko guyot，最大的 CH4 含量（3.9-6.5 nM）主要与山顶上方的次表层（10-300 米）有关。然而，在盖奥特西坡 1000 米处检测到了另一个甲烷羽流（6 nM）。我们认为甲烷的最大值是由黑潮延伸或深层漩涡的影响造成的。神宫巨蛋上空的 CH4 分布与开阔海域相似。最大的甲烷浓度（3.8-6 nM）出现在山顶上方的次表层。科科和神宫表层（过饱和度为 5-52 %）的甲烷浓度都超过了大气平衡浓度。次表层的甲烷含量和过饱和度至少是之前在公海测量值的两倍。我们认为，高甲烷含量和过饱和度是由海山上方水柱中甲烷生成增强造成的。据估计，甲烷进入大气的通量，科科和神宫分别为 1.4 至 16.3 μmol m-2 天-1 和 0.5 至 6.5 μmol m-2 天-1。计算得出的科科（8.37 μmol m-2 天-1）和神宫（2.8 μmol m-2 天-1）的平均通量明显高于开阔洋和沿岸洋的平均通量。鉴于甲烷在大气中的大量贡献，应重新考虑全球甲烷预算。

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引用次数: 0

Ocean-atmosphere-ice processes in the Ross Sea: A review 罗斯海的海洋-大气-冰过程：综述

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-sea Research Part Ii-topical Studies in Oceanography

Pub Date : 2024-10-11 DOI: 10.1016/j.dsr2.2024.105429

Pierpaolo Falco , Giuseppe Aulicino , Pasquale Castagno , Vincenzo Capozzi , Paola de Ruggiero , Angela Garzia , Antonino Ian Ferola , Yuri Cotroneo , Alessio Colella , Giannetta Fusco , Stefano Pierini , Giorgio Budillon , Enrico Zambianchi , Giancarlo Spezie

The Ross Sea has been the site of extensive investigations since the earliest days of polar exploration. The International Geophysical Year of 1957-58 enhanced research activities with the establishment of scientific stations and the collection of oceanographic observations in the area. While many features of its oceanography, ecology, physics, glaciology, geology, and biogeochemistry are known, recent advances provide new insights into its structure and function, as well as into its relationship to global climate. We present a comprehensive review of the advances of understanding the main processes occurring in the area, such as the formation of dense shelf water and the production of Antarctic Bottom Water (AABW), as well as the main drivers (at both large and local scales) of local dynamics and water mass variability. We also summarize the main modeling applications, which are still limited and need to be improved using high-resolution models and, locally, limited-area models to explain processes driven mainly by thermodynamics and water-mass transformations. The Ross Sea forms the most saline AABW due to the activity of two polynyas in the western sector. A salinity gradient occurs on the shelf, with fresh Low Salinity Shelf Waters concentrated in the eastern Ross Sea, which is influenced by the inflow of fresh water from the Amundsen and Bellingshausen Seas. This freshwater inflow was thought to be the cause of a multi-decadal freshening of the High Salinity Shelf Water, precursor to the AABW, although a rebound in salinity in the Ross Sea has been observed since 2014. The increase in salinity has also affected the production of AABW, with the respective rebound occurring almost simultaneously.

自极地探索活动开始以来，罗斯海一直是广泛调查的地点。1957-58 国际地球物理年加强了研究活动，在该地区建立了科学站并收集海洋观测数据。虽然极地的海洋学、生态学、物理学、冰川学、地质学和生物地球化学的许多特征已为人所知，但最近的研究进展使人们对其结构和功能以及与全球气候的关系有了新的认识。我们全面回顾了在了解该地区发生的主要过程（如致密陆架水的形成和南极底层水（AABW）的产生）方面取得的进展，以及当地动态和水量变化的主要驱动因素（在大尺度和局部尺度上）。我们还总结了主要的建模应用，这些应用仍然有限，需要利用高分辨率模型和局部有限区域模型加以改进，以解释主要由热力学和水团转化驱动的过程。由于西段两个多旋流的活动，罗斯海形成了盐度最高的陆地断裂带。陆架上出现了盐度梯度，新鲜的低盐度陆架水集中在罗斯海东部，这是受阿蒙森海和贝林斯豪森海淡水流入的影响。这种淡水流入被认为是造成高盐度大陆架水（AABW 的前体）多年清新的原因，不过自 2014 年以来，已观察到罗斯海盐度回升。盐度的增加也影响了阿拉伯湾水的生成，而各自的反弹几乎同时发生。

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引用次数: 0

Exploring sea ice transport dynamics at the eastern gate of the Ross Sea 探索罗斯海东门的海冰迁移动力学

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-sea Research Part Ii-topical Studies in Oceanography

Pub Date : 2024-10-11 DOI: 10.1016/j.dsr2.2024.105428

Naomi Krauzig , Daniela Flocco , Stefan Kern , Enrico Zambianchi

As Antarctic sea ice extent continues to reach record lows, significant efforts have been directed towards understanding the underlying processes and their regional differences within the Southern Ocean. Here, we explore the dynamics of zonal sea ice transport at the eastern gate of the Ross Sea from 1988 to 2023 using GIOMAS-model and ERA5-reanalysis data. Our analysis reveals a modest overall increase in eastward sea ice transport (3.721 ± 0.672 km³/month per decade), with diverging trends in the coastal and open ocean zones. Driven by easterly winds and the Antarctic Slope Current, the predominant westward transport in the coastal region experienced a significant rise during the early 2000s, followed by a steep decline post-2011. Conversely, driven by the Antarctic Circumpolar Current, the strong open-ocean transport exhibited a moderate increase towards the Amundsen Sea until the late 1990s, which was interrupted by a reversal in 2007. The variability of zonal sea ice transport and its underlying conditions (sea ice concentration, thickness, and zonal drift) revealed considerable shifts throughout the different decades and on seasonal scales. During austral winter, approximately half of the zonal sea ice transport variability seems to be driven by large-scale teleconnections, including the Southern Annular Mode, Southern Oscillation Index, Amundsen Sea Low and the Zonal Wave 3 with considerable impacts on the wind stress field. Whereas during summer, the Southern Oscillation Index emerges as the dominant driver, exhibiting a significant positive correlation (r=0.55, p<0.001) that reflects the influence of the El Niño-Southern Oscillation, while other teleconnections play minimal roles. Our study highlights the complex nature of sea ice transport through the eastern gate of the Ross Sea towards the Amundsen Seas, where contrasting climatic conditions are known to occur.

由于南极海冰面积持续创历史新低，人们一直在努力了解南大洋的基本过程及其区域差异。在此，我们利用 GIOMAS 模型和 ERA5 分析数据，探讨了 1988 年至 2023 年罗斯海东门海冰输送的动态变化。我们的分析表明，海冰向东输送总体上略有增加（每十年 3.721 ± 0.672 千米³/月），沿岸带和开阔洋带的趋势不同。在东风和南极斜坡洋流的驱动下，沿岸地区主要的西向传输量在 2000 年代初显著增加，2011 年后急剧下降。相反，在南极环极洋流的驱动下，强大的公海运移在 20 世纪 90 年代末之前一直呈现出向阿蒙森海的适度增长，2007 年的逆转中断了这一增长。带状海冰传输及其基本条件（海冰浓度、厚度和带状漂移）的变化显示，在不同的年代和季节尺度上都有相当大的变化。在澳大利亚冬季，约有一半的海冰输送带变化似乎是由大尺度遥联系驱动的，包括南环流模式、南方涛动指数、阿蒙森海低海平面和对风应力场有重大影响的带状波 3。而在夏季，南方涛动指数是主要的驱动因素，表现出显著的正相关性（r=0.55，p<0.001），反映了厄尔尼诺-南方涛动的影响，而其他远缘联系的作用微乎其微。我们的研究强调了海冰通过罗斯海东门向阿蒙森海迁移的复杂性，众所周知，在那里会出现截然不同的气候条件。

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