Article
Environmental Sciences
Florent Garnier, Marion Bocquet, Sara Fleury, Jerome Bouffard, Michel Tsamados, Frederique Remy, Gilles Garric, Aliette Chenal
Summary: The relatively stable conditions of the sea ice cover in the Antarctic seem to be changing recently, and it is important to provide estimates of sea ice thickness and volume to anticipate potential changes. The study found that sea ice thickness and volume have been decreasing, particularly after 2016, in all regions except the Amundsen-Bellingshausen sea sector. This may indicate significant ongoing changes in the Antarctic sea ice.
Article
Geochemistry & Geophysics
Hoyeon Shi, Sang-Moo Lee, Byung-Ju Sohn, Albin J. Gasiewski, Walter N. Meier, Gorm Dybkjar, Sang-Woo Kim
Summary: This study aims to develop a new retrieval algorithm for snow depth, sea ice thickness, bulk density, and ice freeboard in the Arctic winter by combining CryoSat-2 with passive microwave and infrared measurements. The algorithm combines two parameterizations with hydrostatic balance and radar wave speed correction equations to obtain solutions for the four variables. The results show good agreement with airborne snow depth, total freeboard, and mooring ice draft measurements, and the retrieved multiyear sea ice bulk density is more consistent with in situ measurements compared to previous parameterizations.
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
(2023)
Article
Oceanography
Victoria Hill, Bonnie Light, Michael Steele, Andrew Lowy Sybrandy
Summary: Novel observations were collected on the seasonal evolution of an ice algal bloom on the Chukchi shelf using two autonomous buoys. The differences in ice algae biomass under each buoy were driven by variations in snow thickness, with nutrients being limiting at the low snow site and light being limiting at the high snow site.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Environmental Sciences
Geoffrey Dawson, Jack Landy, Michel Tsamados, Alexander S. Komarov, Stephen Howell, Harry Heorton, Thomas Krumpen
Summary: Satellite observations have been constrained to winter months, but a new method using neural networks trained with summer images has enabled accurate measurements of pan-Arctic sea ice thickness. The results show that the freeboard distributions in May and September closely match expected patterns of sea ice melt, although CryoSat-2 freeboards underestimate ice thickness compared to other observations, especially over thicker multi-year sea ice. Addressing uncertainties in the conversion from radar freeboard to ice thickness is crucial for creating a comprehensive pan-Arctic summer sea ice thickness dataset.
REMOTE SENSING OF ENVIRONMENT
(2022)
Article
Engineering, Marine
Yanze Zhang, Nengfang Chao, Fupeng Li, Lianzhe Yue, Shuai Wang, Gang Chen, Zhengtao Wang, Nan Yu, Runzhi Sun, Guichong Ouyang
Summary: The rapid decline of Arctic sea ice has had significant impacts on the global climate, polar ecosystems, and shipping routes. Precise long-term and high-resolution estimates of Arctic sea ice changes are crucial for adapting to climate change and developing Arctic marine resources. This study comprehensively analyzes the characteristics of Arctic sea ice thickness, volume, and extent using satellite altimeter data and investigates the relationship between surface temperature and wind field. The results show consistent loss trends in Arctic sea ice freeboard, thickness, extent, and area, with a significant decrease in sea ice volume. Sea surface temperature and wind field are identified as important influencing factors on Arctic sea ice variations.
JOURNAL OF MARINE SCIENCE AND ENGINEERING
(2023)
Article
Remote Sensing
Jinghui Jiang, Shanwei Liu, Qintin Sun, Jianhua Wan
Summary: Arctic sea ice change is critical for global climate environment. The accuracy of sea ice thickness is crucial in studying polar and global climate change. This study presents a processing chain for sea ice thickness estimation by comparing different mean sea surface height models and optimizing the traditional sea ice thickness model, which effectively improves the accuracy of sea ice thickness.
INTERNATIONAL JOURNAL OF REMOTE SENSING
(2023)
Article
Astronomy & Astrophysics
S. W. Fons, N. T. Kurtz, M. Bagnardi, A. A. Petty, R. L. Tilling
Summary: The launch of NASA's ICESat-2 laser altimeter in 2018 has provided valuable additional data to the polar altimetry record. By comparing ICESat-2 and ESA's CryoSat-2, researchers have found improvements in the retrieval process for Antarctic snow freeboard. While the two sensors show good agreement in coincident data, differences in geometric and frequency sampling methods can impact the freeboard distributions.
EARTH AND SPACE SCIENCE
(2021)
Article
Geosciences, Multidisciplinary
Feng Xiao, Shengkai Zhang, Jiaxing Li, Tong Geng, Yue Xuan, Fei Li
Summary: Arctic sea ice thickness plays a crucial role in climate research and environmental change, with satellite altimeters being a key tool in accurately measuring sea ice thickness. The study found that using waveform parameters for leads detection provides improved results, and optimizing the model for converting freeboard to thickness considering incomplete snow penetration enhances thickness estimates. The research also validates the thickness estimates and analyzes variations in Arctic sea ice thickness using different data sources.
SCIENCE CHINA-EARTH SCIENCES
(2021)
Article
Engineering, Electrical & Electronic
Hangyu Lyu, Weimin Huang, Masoud Mahdianpari
Summary: Sea ice has a profound influence on ocean circulation, the polar environment, biology, climate, and commercial activities. Spaceborne synthetic aperture radar (SAR) has been widely used for sea ice sensing due to its all-weather imaging capabilities. This study provides a meta-analysis of 182 articles published in the last decade on spaceborne polarimetric SAR-data-based sea ice sensing, aiming to compare different techniques and identify current challenges.
IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING
(2022)
Article
Geosciences, Multidisciplinary
P. Anhaus, C. Katlein, M. Nicolaus, M. Hoppmann, C. Haas
Summary: The study found that during the summer-autumn transition period in 2018, more snow accumulated on refrozen melt ponds compared to adjacent bare ice, leading to a reduction in light transmittance of the ponds even below that of bare ice. This situation, not described in the literature before, could have significant implications for autumn ecosystem activity, oceanic heat budget, and thermodynamic ice growth.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Oceanography
Benjamin A. Lange, Christian Haas, Alfonso Mucci, Justin F. Beckers, J. Alec Casey, Steve Duerksen, Mats A. Granskog, Ido Hatam, Andrea Niemi, Anke Reppchen, Christine Michel
Summary: This study analyzed ice cores from the Lincoln Sea and found that multi-year ice has a higher snow contribution compared to first-year ice, due to the accumulation of more snowmelt water over multiple seasons. Additionally, high snow contributions were observed on the surface of older first-year ice cores, likely due to flooding events and snow-ice formation.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2021)
Article
Engineering, Electrical & Electronic
Qi Liang, Chunxia Zhou, Lei Zheng
Summary: This study analyzes the impact of basal melt rate on ice shelf buttressing effect and discharge of grounded ice into the ocean. By utilizing a Lagrangian framework, the researchers improved the derivation of basal melt rate and applied it to a case study of the Shackleton ice shelf, providing more spatially coherent patterns of ice shelf surface elevation changes and reducing uncertainty in basal melt rate calculation.
IEEE JOURNAL OF SELECTED TOPICS IN APPLIED EARTH OBSERVATIONS AND REMOTE SENSING
(2021)
Article
Oceanography
Jack C. Landy, Jerome Bouffard, Chris Wilson, Stefanie Rynders, Yevgeny Aksenov, Michel Tsamados
Summary: The study shows that utilizing an objective mapping approach to determine sea surface height from proximal lead samples located on the orbital track and nearby tracks can improve the precision of sea ice radar freeboard estimation. By analyzing the covariance of historic CryoSat-2 Arctic lead observations, researchers were able to determine optimal SSH and error estimates for sea ice floe locations, leading to up to 20% increase in radar freeboard precision. This new method can be generalized to all present and historic polar altimetry missions, providing a more accurate way to measure sea ice thickness in a warming climate.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2021)
Article
Geosciences, Multidisciplinary
Livia Jakob, Noel Gourmelen
Summary: For the first time, we have produced a detailed record of ice loss from glaciers globally using CryoSat-2 swath interferometric radar altimetry. Our study reveals that between 2010 and 2020, glaciers lost a total of 272 +/- 11 Gt yr(-1) of ice, accounting for 2% of their total volume. Surface mass balance anomaly was the dominant factor, contributing to 89% +/- 5% of the total ice loss, while ice discharge anomaly accounted for 11% +/- 1% of the total ice loss, or 28% +/- 2% when excluding land-terminating sectors. Strong discharge anomaly was observed in areas affected by changing oceanic conditions and surrounded by lakes and fjords.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Flor Vermassen, Helen Coxall
Summary: Analysis of sediment cores from areas with persistent Arctic sea ice today shows that a subpolar species connected to Atlantic water extended into the Arctic Ocean during the Last Interglacial. This suggests that summers in the Arctic were likely ice-free during that period.
Article
Fisheries
Sarah M. Maes, Henrik Christiansen, Felix C. Mark, Magnus Lucassen, Anton Van de Putte, Filip A. M. Volckaert, Hauke Flores
Summary: The study revealed high genetic diversity in polar cod in the Arctic Ocean, with absence of spatial population structure between different sampling regions indicating ongoing gene flow. The high level of connectivity in polar cod is important for maintaining populations across wide spatial scales.
JOURNAL OF FISH BIOLOGY
(2021)
Article
Biodiversity Conservation
Carmen L. David, Fokje L. Schaafsma, Jan A. van Franeker, Evgeny A. Pakhomov, Brian P. V. Hunt, Benjamin A. Lange, Giulia Castellani, Angelika Brandt, Hauke Flores
Summary: The survival of larval Antarctic krill is largely dependent on the presence of sea ice in the winter, which not only provides food and shelter, but also reduces competition and predation risk. The benefits of sea ice as a suitable winter habitat for larval krill highlight the potential impact of projected declines in sea ice on the krill population.
Review
Oceanography
Pierre Priou, Anna Nikolopoulos, Hauke Flores, Rolf Gradinger, Erin Kunisch, Christian Katlein, Giulia Castellani, Torsten Linders, Jorgen Berge, Jonathan A. D. Fisher, Maxime Geoffroy
Summary: This study reveals the under-ice distribution of epipelagic and mesopelagic organisms at the Arctic-Atlantic gateway in spring, during the midnight sun period. The epipelagic surface scattering layer is primarily composed of copepods in the top 60 meters, while the mesopelagic deep scattering layer consists mainly of fish and extends between 280 meters and 600 meters.
PROGRESS IN OCEANOGRAPHY
(2021)
Article
Oceanography
Benjamin A. Lange, Christian Haas, Alfonso Mucci, Justin F. Beckers, J. Alec Casey, Steve Duerksen, Mats A. Granskog, Ido Hatam, Andrea Niemi, Anke Reppchen, Christine Michel
Summary: This study analyzed ice cores from the Lincoln Sea and found that multi-year ice has a higher snow contribution compared to first-year ice, due to the accumulation of more snowmelt water over multiple seasons. Additionally, high snow contributions were observed on the surface of older first-year ice cores, likely due to flooding events and snow-ice formation.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2021)
Article
Biodiversity Conservation
Fokje L. Schaafsma, Carmen L. David, Doreen Kohlbach, Julia Ehrlich, Giulia Castellani, Benjamin A. Lange, Martina Vortkamp, Andre Meijboom, Anna Fortuna-Wunsch, Antonia Immerz, Hannelore Cantzler, Apasiri Klasmeier, Nadezhda Zakharova, Katrin Schmidt, Anton P. Van de Putte, Jan Andries van Franeker, Hauke Flores
Summary: This study summarizes the allometric relationships of zooplankton and nekton species in polar marine food webs. It fills knowledge gaps on relationships between length and mass for understudied animals, seasons, and maturity stages. Intra-specific variation in length-mass relationships is observed for several species depending on season. Generalized regression models show potential use but need further investigation regarding sex, maturity stages, or age classes. Other allometric measurements provide useful models for estimating length or mass in diet studies, but their suitability may depend on species or developmental stages.
Article
Limnology
Erin H. Kunisch, Martin Graeve, Rolf Gradinger, Hauke Flores, Oystein Varpe, Bodil A. Bluhm
Summary: During the productive polar day, zooplankton and sea-ice amphipods play a critical role in transferring energy from primary producers to higher trophic-level species. Recent studies suggest higher biological activity of these invertebrates during polar night than previously assumed, but the mechanisms behind their activity remain unknown.
LIMNOLOGY AND OCEANOGRAPHY
(2023)
Review
Ecology
Julian Gutt, Stefanie Arndt, David Keith Alan Barnes, Horst Bornemann, Thomas Brey, Olaf Eisen, Hauke Flores, Huw Griffiths, Christian Haas, Stefan Hain, Tore Hattermann, Christoph Held, Mario Hoppema, Enrique Isla, Markus Janout, Celine Le Bohec, Heike Link, Felix Christopher Mark, Sebastien Moreau, Scarlett Trimborn, Ilse van Opzeeland, Hans-Otto Poertner, Fokje Schaafsma, Katharina Teschke, Sandra Tippenhauer, Anton Van de Putte, Mia Wege, Daniel Zitterbart, Dieter Piepenburg
Summary: Systematic long-term studies on ecosystem dynamics are lacking in the East Antarctic Southern Ocean. This study proposes a framework for a cross-disciplinary long-term study in the eastern Weddell Sea and adjacent areas, which have so far experienced comparatively muted climate and environmental change. By establishing an observatory and conducting regular surveys, researchers aim to explore and map long-term changes in ocean dynamics, geochemistry, biodiversity, and ecosystem functions and services. The integrated approach will provide crucial data for understanding and projecting the consequences of climate change and supporting conservation efforts in the Southern Ocean.
Article
Multidisciplinary Sciences
Pauline Snoeijs-Leijonmalm, Hauke Flores, Serdar Sakinan, Nicole Hildebrandt, Anders Svenson, Giulia Castellani, Kim Vane, Felix C. Mark, Celine Heuze, Sandra Tippenhauer, Barbara Niehoff, Joakim Hjelm, Jonas Hentati Sundberg, Fokje L. Schaafsma, Ronny Engelmann
Summary: The retreating ice cover of the Central Arctic Ocean has raised concerns about the future fisheries in the region. However, little is known about the presence of harvestable fish stocks in this vast ecosystem. A recent study found a 3170-kilometer-long deep scattering layer (DSL) with zooplankton, small fish, and low abundances of Atlantic cod in the Atlantic water layer of the Eurasian Basin. The potential fish abundance was found to be far below sustainable levels and is expected to remain so due to the low productivity of the Central Arctic Ocean.
Article
Environmental Sciences
J. Ehrlich, B. A. Bluhm, I Peeken, P. Massicotte, F. L. Schaafsma, G. Castellani, A. Brandt, H. Flores
Summary: Drastic environmental changes in the Svalbard region, primarily driven by climate warming, have led to shifts in sea-ice-associated community structure, impacting carbon cycling. Sympagic biota play a crucial role as a source, sink, and transmitter of carbon in this changing ecosystem, with under-ice fauna proving to be vital for carbon flux in the context of climate change.
ELEMENTA-SCIENCE OF THE ANTHROPOCENE
(2021)
Review
Environmental Sciences
Nadja S. Steiner, Jeff Bowman, Karley Campbell, Melissa Chierici, Eeva Eronen-Rasimus, Marianne Falardeau, Hauke Flores, Agneta Fransson, Helena Herr, Stephen J. Insley, Hanna M. Kauko, Delphine Lannuzel, Lisa Loseto, Amanda Lynnes, Andy Majewski, Klaus M. Meiners, Lisa A. Miller, Loic N. Michel, Sebastien Moreau, Melissa Nacke, Daiki Nomura, Letizia Tedesco, Jan Andries van Franeker, Maria A. van Leeuwe, Pat Wongpan
Summary: A comprehensive synthesis of the sea-ice ecosystem and its linked ecosystem services shows that sea-ice ecosystems provide habitat, food, and cultural services. The global emissions driving climate change are directly impacting the decline of sea-ice ecosystems and their services, with negative consequences for human well-being and biodiversity. Reduction in carbon emissions is identified as a key mitigation measure to protect sea-ice ecosystems and their services.
ELEMENTA-SCIENCE OF THE ANTHROPOCENE
(2021)
Article
Geography, Physical
Christian Haas, Patricia J. Langhorne, Wolfgang Rack, Greg H. Leonard, Gemma M. Brett, Daniel Price, Justin F. Beckers, Alex J. Gough
Summary: The study used airborne, single-frequency electromagnetic induction surveys to investigate the thickness and spatial distribution of landfast sea ice and sub-ice platelet layer (SIPL) in McMurdo Sound. The results showed SIPL thicknesses of up to 8 meters near the ice shelf front and interannual variability of up to 2 meters. The surveys provided high-resolution spatial information on small-scale SIPL thickness variability and suggested the presence of persistent peaks linked to the geometry of outflow from under the ice shelf.