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Advances in Polar Science 2024年第1期35卷 123-131页

作者： HU Ji XUE Siyou ZHAO Jun LI Dong ZHANG Haifeng YU Peisong ZHANG Cai YANG Xufeng PAN Jianming Key Laboratory of Marine Ecosystem Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China College of Ocean and Earth Sciences Xiamen UniversityXiamen 361102China

The Southern Ocean is an important carbon sink pool and plays a critical role in the global carbon cycling.The Amundsen Sea was reported to be highly productive in inshore area in the Southern Ocean.In order to investigate the influence of transparent exopolymer particles(TEP)on the behavior of dissolved organic carbon(DOC)in this region,a comprehensive study was conducted,encompassing both open water areas and highly productive polynyas.It was found that microbial heterotrophic metabolism is the primary process responsible for the production of humic-like fluorescent components in the open ocean.The relationship between apparent oxygen utilization and the two humic-like components can be accurately described by a power-law function,with a conversion rate consistent with that observed globally.The presence of TEP was found to have little impact on this process.Additionally,the study revealed the accumulation of DOC at the sea surface in the Amundsen Sea Polynya,suggesting that TEP may play a critical role in this phenomenon.These findings contribute to a deeper understanding of the dynamics and surface accumulation of DOC in the Amundsen Sea Polynya,and provide valuable insights into the carbon cycle in this region.

关键词： dissolved organic matter chromophoric dissolved organic matter excitation-emission matrix coupled with parallel factor analysis transparent exopolymer particles Amundsen Sea antarctica

Methods for ice velocity mapping in West antarctica using historical optical satellite images

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Advances in Polar Science 2024年第2期35卷 252-263页

作者： ZHANG Yujie AN Lu TANG Leyue LI Hongwei HE Meixi LI Rongxing Center for Spatial Information Science and Sustainable Development Applications Tongji UniversityShanghai 200092China College of Surveying and Geo-Informatics Tongji UniversityShanghai 200092China

The Antarctic Ice Sheet harbors more than 90%of the Earth ice mass,with significant losses experienced through dynamic thinning,particularly in West antarctica.The crucial aspect of investigating ice mass balance in historical periods preceding 1990 hinges on the utilization of ice velocities derived from optical satellite images.We employed declassified satellite images and Landsat images with normalized cross correlation based image matching,adopting an adaptive combination of skills and methods to overcome challenges encountered during the mapping of historical ice velocity in West antarctica.A basin-wide synthesis velocity map encompassing the coastal regions of most large-scale glaciers and ice shelves in West antarctica has already been successfully generated.Our results for historical ice velocities cover over 70%of the grounding line in most of the West Antarctic basins.Through adjustments,we uncovered overestimations in ice velocity measurements over an extended period,transforming our ice velocity map into a spatially deterministic,temporally average version.Among all velocity measurements,Thwaites Glacier exhibited a notable spatial variation in the fastest ice flowline and velocity distribution.Overestimation distributions on Thwaites Glacier displayed a clear consistency with the positions of subsequent front calving events,offering insights into the instabilities of ice shelves.

关键词： antarctica ice velocity overestimation correction historical imagery

Geophysical evidence of a large occurrence of mud volcanoes associated with gas plumbing system in the Ross Sea(antarctica)

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Geoscience Frontiers 2024年第1期15卷 304-324页

作者： Martina Busetti Riccardo Geletti Dario Civile Chiara Sauli Giuseppe Brancatelli Edy Forlin Daniela Accettella Lorenza Barro Savonuzzi Laura De Santis Aldo Vesnaver Andrea Cova National Institute of Oceanography and Applied Geophysics–OGS Borgo Grotta Gigante 42/c34010 SgonicoTriesteItaly

Seafloor and buried reliefs occur along continental margin of the Ross Sea(antarctica).These features are several kilometres wide and tens of metres high,exhibiting cone or flat-top dome shapes.Previous studies have proposed a volcanic or glacial origin for these formations,but these hypotheses do not account for all the available evidence.In this study,we use morpho-bathymetric data,intermediate resolution multichannel seismic and high resolution chirp profiles,as well as magnetic lines to investigate these clusters of mounds.By employing targeted processing techniques to enhance the geophysical characterization of the seafloor and buried reliefs,and to understand the underlying geological features,we propose that the reliefs are mud volcanoes.Some of these formations appear to be associated with a plumbing system,as indicated by acoustic anomalies linked to sediment containing gas.These formations are likely fed by clayey source rocks of Miocene age.Additionally,other reliefs might be the result of mud mobilisation caused by gravity instability and fluid overpressure.

关键词： Ross Sea antarctica Mud volcanoes Gas plumbing system Gas hydrate Bottom Simulating Reflector

Middle Eocene chondrichthyan fauna from Antarctic Peninsula housed in the Museo de La Plata,Argentina

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Advances in Polar Science 2024年第1期35卷 14-47页

作者： Martina CHARNELLI Soledad GOUIRIC-CAVALLI Marcelo A.REGUERO Alberto L.CIONE Agencia Nacional de Promoción Científica y Tecnológica(ANPCyT) Godoy Cruz 2370Argentina División Paleontología Vertebrados Museo de La PlataPaseo del Bosque s/nLa Plata B1900FWAArgentina Facultad de Ciencias Naturales y Museo de La Plata(FCNyM) Universidad Nacional de La Plata(UNLP)La Plata CP 1900Argentina Instituto Antártico Argentino(IAA) General San Martín B1650HMKArgentina Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET) Buenos Aires C1425FQBArgentina

In recent years,the taxonomy and systematics of the cartilaginous fish taxa from the Eocene La Meseta Formation of Seymour(Marambio)Island,antarctica have been extensively discussed in a series of papers,resulting in a complete revision of the Antarctic Eocene ichthyofauna housed in the Vertebrate Paleontology collection of the Museo de La Plata,Argentina.This collection constitutes one of the largest and taxonomically most diverse in the world,with approximately 20000 specimens,which provides a solid database used for the analysis of qualitative and quantitative chondrichthyan taxonomic composition.The information provided herein might be useful to understand the sudden decline in chondrichthyan taxonomic diversity towards the top of La Meseta Formation as well as its potential relationship with environmental changes during the Eocene.

关键词： Gondwana antarctica Paleogene ichthyofauna Seymour(Marambio)Island

Belgica antarctica(Diptera: Chironomidae): A natural modelorganism for extreme environments

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Insect Science 2022年第1期29卷 2-20页

作者： Iryna Kozeretska Svitlana Serga Pavlo Kovalenko Volodymyr Gorobchyshynand Peter Convey National Antarctic Scientific Center of Ukraine 01601Taras Shevchenko blv.16KyivUkraine Taras Shevchenko National Universityof Kyiv Department General and Medical Genetics01601Volodymyrska str.64/13KyivUkraine State Institution«Institute for Evolu-tionary Ecology of the National Academy of Sciences of Ukraine» Department of Population Dynamics03143Lebedeva str.37KyivUkraine and4British Antarctic SurveyNERCHigh CrossMadingley RoadCambridge CB30ETUnited Kingdom

Belgica antarctica(Diptera:Chironomidae),a brachypterous midge endemicto the maritime Antarctic,was first described in 1900.Over more than a century of study,a vast amount of information has been compiled on the species(3750000 Google searchresults as of January 10,2021),encompassing its ecology and biology,life cycle and re-production,polytene chromosomes,physiology,biochemistry and,increasingly,omics.In2014,B.antarctica’s genome was sequenced,further boosting research.Certain develop-mental stages can be cultured successfully in the laboratory.Taken together,this wealthof information allows the species to be viewed as a natural model organism for studies ofadaptation and function in extreme environments.

关键词： Belgica antarctica Chironomidae stress adaptation antarctica

Sentinel-1 EW mode dataset for antarctica from 2014–2020 produced by the CASEarth Cloud Service Platform

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Big Earth Data 2022年第4期6卷 385-400页

作者： Dong Liang Huadong Guo Lu Zhang Haipeng Lia Xuezhi Wang Key Laboratory of Digital Earth Science Aerospace Information Research InstituteChinese Academy of SciencesBeijingChina University of Chinese Academy of Sciences BeijingChina International Research Center of Big Data for Sustainable Development Goals BeijingChina Computer Network Information Center Chinese Academy of SciencesBeijingChina

antarctica plays an important role in research on global change,and its unique geography,ocean,climate,and environment pro-vide an ideal place for humankind to understand Earth’s evolution.Remote sensing provides an effective means to monitor and observe large-scale processes on the continent.Synthetic aperture radar(SAR)in particular provides the capability for all-weather Earth observation.The Sentinel-1A and Sentinel-1B SAR satellites have ideal ground coverage and imaging frequency for observing antarctica.This study developed a dataset of 69,586 Sentinel-1 EW mode satellite images of the Antarctic ice sheet from October 2014 to December 2020.The dataset was processed with the European Space Agency Sentinel Application Platform(SNAP)and a Python batch scheduling tool on the Big Earth Data Cloud Service Platform of the Chinese Academy of Sciences Big Earth Data Science Engineering Program(CASEarth).Several data processing operations were implemented to process the raw dataset,including radiometric calibration,invalid edge removal,geocoding,data reprojection to an Antarctic projection,data compression to TIFF format,and construction of image pyramids.The dataset is avail-able at http://***/10.11922/sciencedb.j00076.00085.

关键词： Big Earth data CASEarth cloud computing Sentinel-1 antarctica

Evaluating Parameterizations for Turbulent Fluxes over the Landfast Sea-Ice Surface in Prydz Bay, antarctica

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Advances in Atmospheric Sciences 2023年第10期40卷 1816-1832页

作者： Fangyuan CHENG Qinghua YANG Changwei LIU Bo HAN Shijie PENG Guanghua HAO School of Atmospheric Sciences Sun Yat-sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519080China National Marine Environmental Forecasting Center Beijing 100081China

It is crucial to appropriately determine turbulent fluxes in numerical models.Using data collected in East antarctica from 8 April to 26 November 2016,this study evaluates parameterization schemes for turbulent fluxes over the landfast seaice surface in five numerical models.The Community Noah Land Surface Model with Multi-Parameterizations Options(Noah_mp)best replicates the turbulent momentum flux,while the Beijing Climate System Model(BCC_CSM)produces the optimum sensible and latent heat fluxes.In particular,two critical issues of parameterization schemes,stability functions and roughness lengths,are investigated.Sensitivity tests indicate that roughness lengths play a decisive role in model performance.Based on the observed turbulent fluxes,roughness lengths over the landfast sea-ice surface are calculated.The results,which can provide a basis for setting up model parameters,reveal that the dynamic roughness length(z0m)increases with the increase of frictional velocity(u*)when u*≤0.4 m s^(−1) and fluctuates around 10^(−3 )m when u*>0.4 m s^(−1);thermal roughness length(z0t)is linearly related to the temperature gradient between air and sea-ice surface(ΔT)with a relation of lg(z0t)=−0.29ΔT−3.86;and the mean water vapor roughness length(z0q)in the specific humidity gradient(Δq)range ofΔq≤−0.6 g kg^(−1) is 10^(−6) m,3.5 times smaller than that in the range ofΔq˃−0.6 g kg^(−1).

关键词： turbulent fluxes antarctica landfast sea-ice surface parameterization evaluating numerical models

Thickness simulation of landfast ice along Mawson Coast,East antarctica based on a snow/ice high-resolution thermodynamic model

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Advances in Climate Change Research 2022年第3期13卷 375-384页

作者： Xin-Qing LI Feng-Ming HUI Jie-Chen ZHAO Meng-Xi ZHAI Xiao CHENG School of Geospatial Engineering and Science Sun Yat-sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Harbin Engineering University Qingdao Graduate School Qingdao Innovation and Development Base(Center)of Harin Engineering UniversityQingdao266000China MNR Key Laboratory for Polar Science Polar Research Institute of ChinaShanghai 200136China

Landfast ice plays an important role in atmosphere‒ocean interactions and ecosystems in the near coast area of antarctica.Understanding the characteristics and variations of landfast ice is crucial to the study of climates and field activities in Antarctic.In this study,a high-resolution thermodynamic snow-ice(HIGHTSI)model was applied to simulate the seasonal changes of landfast ice along the Mawson Coast,East antarctica,through ERA-Interim reanalysis data.Four ocean heat-flux(Fw)values(10,15,20 and 25 W m−2)were used in sensitivity experiments.The results showed that it is reasonable to simulate landfast ice using the HIGHTSI model,and the simulation of landfast ice thickness matched best well with field measurements when Fw was 20 W m^(−2).Then,2-D distributions of landfast ice from 2006 to 2018 were modeled by HIGHTSI with 2-D ERA-Interim reanalysis data in a 0.125°×0.125°cell grid as external forcing.The results showed that fast ice was thicker along the coast and thinner near open water,and usually reaches its maximal thickness in October,varying from 1.2 to 2.0 m through the study area.There was no statistical trend for the thickness during the study period.

关键词： Landfast ice Modeling HIGHTSI antarctica

The absolute gravity measurements from A10 along the 1240 km route in East antarctica

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Science China Earth Sciences 2022年第12期65卷 2417-2420页

作者： Yuande YANG Fei LI Key Laboratory of Polar Surveying and Mapping Ministry of Natural Resources/Chinese Antarctic Center of Surveying and MappingWuhan UniversityWuhan 430079China

1.Introduction Gravity data provide significant insights on ice mass balance and geological structure studies in antarctica,which is the largest ice sheet on the earth(Xu,2001;Alley et al.,2005).Since the 1950s,the gravity ties have been introduced to antarctica from Australia and South America(Sledzinski,2001;Amalvict,2004),which adopted the approach of relative gravity measurements with pendulum or spring gravimeters.Absolute gravity measurements were later conducted in antarctica by several countries to provide gravity bases and to derive its dynamic change with the technique advance in gravimeter instrumentation.By 2009,25 absolute gravity surveys had been carried out at 14 stations in antarctica(Mäkinen et al.,2007;E et al.,2007,2011;Kazama et al.,2013).

关键词： antarctica East absolute

Numerical simulation of the dynamic effects of grounding icebergs on summer circulation in Prydz Bay,antarctica

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Advances in Polar Science 2022年第2期33卷 135-144页

作者： HAN Yuxin SHI Jiuxin HOU Saisai XIAO Changhao Physical Oceanography Laboratory Ocean University of ChinaQingdao 266100China Qingdao National Laboratory for Marine Science and Technology Qingdao 266237China

The Regional Ocean Modeling System(ROMS)is employed to create a three-dimensional numerical model of the summer circulation in the Prydz Bay region,antarctica.Consistent with the currents measured using an underway acoustic Doppler current profiler during a Chinese cruise,the simulated current field illustrates the major features of the Prydz Bay circulation,including the Antarctic Slope Current(ASC)along the continental shelf break,the cyclonic Prydz Bay Gyre,and the Prydz Bay Eastern Coastal Current(PBECC).The effects of grounding icebergs D15 and B15 on the circulation in Prydz Bay are investigated via numerical simulations.The results indicate that these giant grounding icebergs substantially affect the flows into and within the bay,which may differ with the different grounding locations.As grounding iceberg D15 is located close to the southwestern part of the West Ice Shelf(WIS),it cuts off the coastal current along the outer edge of the WIS,and the ASC can only enter Prydz Bay from the west side of iceberg D15,whereupon it becomes a main source of the PBECC.Iceberg D15 also weakens the circulation in the bay in general.The relatively small iceberg B15 entered Prydz Bay from 2007 to 2009 and grounded on the southwestern section of the Four Ladies Bank.The numerical experiments indicate that iceberg B15 guides the ASC flowing into the bay around its west side and reduces the width of the inflow on the eastern side of the Prydz Bay Channel.The grounding of iceberg B15 has also led to adjustments of the circulation within the bay,among which the most significant is that the outflow along the western flank of Fram Bank has shifted to the west and become more intensive.

关键词： circulation grounding iceberg numerical simulation Prydz Bay antarctica