Article
Geosciences, Multidisciplinary
S. Stevenson, K. M. Cobb, M. Merrifield, B. Powell, S. Sanchez, J. Nusbaumer, G. O'Connor, A. Atwood
Summary: This study investigates the reconstruction of El Nino events using oxygen isotopic records from tropical corals, and finds that ocean dynamics play a critical role in influencing the isotopic composition of corals and seawater.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geosciences, Multidisciplinary
T. Karpouzoglou, L. de Steur, P. A. Dodd
Summary: This study assesses the contribution of flow over the Northeast Greenland Shelf (NEGS) to the total freshwater transport (FWT) through the Fram Strait. The results show that the NEGS contributes significantly (40%-45%) to the total FWT. However, there is a large seasonal cycle and high uncertainty, making sustained year-round observations on the NEGS essential for better FWT estimates.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Multidisciplinary Sciences
Julie Ann Koehlinger, Jan Newton, John Mickett, LuAnne Thompson, Terrie Klinger
Summary: The Olympic coast, the northern portion of Washington's outer coast, experiences seasonal upwelling and occasional downwelling. Analysis of water temperature records from 2001-2015 found short-term warm events lasting 10-20 days, with temperature anomalies of up to 4.5 degrees C at 40 m depth. These warm events were correlated with northward long-shore winds and upper ocean currents, consistent with downwelling-favorable winds. Near-shore short-term warm events occur during both large-scale marine heatwave events and in the absence of such events when downwelling-favorable winds occur.
Article
Geosciences, Multidisciplinary
Teodora Pados-Dibattista, Christof Pearce, Henrieka Detlef, Jorgen Bendtsen, Marit-Solveig Seidenkrantz
Summary: The study reveals significant variations in water masses and the strength of the East Greenland Current over the past 9.4 kyr in the Northeast Greenland shelf. The stratification of the water column and composition of water masses have undergone major changes in different periods, with influences from Polar Water and Atlantic Water exchanges playing a significant role in shaping water column conditions, especially during the Holocene era.
CLIMATE OF THE PAST
(2022)
Article
Multidisciplinary Sciences
G. W. K. Moore, S. E. L. Howell, M. Brady, X. Xu, K. McNeil
Summary: Ice arches at the northern and southern ends of Nares Strait, a key passage in the Arctic, are forming for shorter durations, leading to increased ice transport and accelerating the export of multi-year ice.
NATURE COMMUNICATIONS
(2021)
Article
Geosciences, Multidisciplinary
Gemma K. O'Connor, Kim M. Cobb, Hussein R. Sayani, Alyssa R. Atwood, Pamela R. Grothe, Samantha Stevenson, Julia K. Baum, Tianran Chen, Danielle C. Claar, Nicholas T. Hitt, Jean Lynch-Stieglitz, Richard A. Mortlock, Gavin A. Schmidt, Rachel Walter
Summary: The study presents reliable reconstructions of El Nino events using coral delta O-18 records from Kiritimati Island during the 2015/16 strong El Nino event. Results show that approximately 70% of the signal in coral delta O-18 anomalies is from sea surface temperature, while the remaining 30% is from seawater delta O-18 anomalies.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Multidisciplinary Sciences
G. E. Moseley, R. L. Edwards, N. S. Lord, C. Spotl, H. Cheng
Summary: Based on the speleothem record from northeast Greenland, dating back to approximately 588 to 549 thousand years ago, it shows at least 3.5 degrees Celsius warmer than present, leading to permafrost thaw and increased precipitation. The results provide important insights into the regional climatic response leading up to the Mid-Brunhes Event, suggesting a warmer Arctic climate.
Article
Environmental Sciences
Hao-Jhe Hong, Huang-Hsiung Hsu
Summary: The Northeast Pacific experienced two record-breaking marine heatwave events during 2013-2015 and summer 2019, causing significant damage to fisheries, marine ecosystems, and climate in North America. This study found that these events were characterized by anomalous circulation patterns and warming sea surface temperatures in the Gulf of Alaska, which were influenced by atmospheric waves originating from the tropical central Pacific in the preceding spring. The findings suggest the important role of tropical Pacific sea surface temperatures in driving summertime temperature variability in the North Pacific.
ENVIRONMENTAL RESEARCH LETTERS
(2023)
Review
Oceanography
Jun Nishioka, Ichiro Yasuda, Toru Hirawake, Tomohiro Nakamura, Yoshiko Kondo, Yuri N. Volkov
Summary: The memorial addresses for Mr. Alexey Fedorovich Shcherbinin and Captain Evgeniy Anikovich Sklizkov highlight their significant roles and leadership in Russian-Japanese collaborative expeditions, expressing deep condolences and honoring their achievements.
PROGRESS IN OCEANOGRAPHY
(2022)
Article
Geography, Physical
Timothy P. P. Lane, Christopher Darvill, Brice Rea, Mike Bentley, James A. A. Smith, Stewart Jamieson, Colm O. Cofaigh, David Roberts
Summary: Understanding ice stream dynamics is important for predicting ice sheet behavior. This study investigates the geomorphological imprint of ice shelves during deglaciation in northeast Greenland. The findings reveal the development of ice shelves, warm-based ice, and thinning of the grounded ice stream margin over time. The study also documents the expansion and retreat of the 79N ice shelf, providing insights into present-day ice shelf landsystem in a warming climate.
EARTH SURFACE PROCESSES AND LANDFORMS
(2023)
Article
Geosciences, Multidisciplinary
Tongtong Xu, Matthew Newman, Antonietta Capotondi, Emanuele Di Lorenzo
Summary: Prolonged and intense marine heatwaves (MHWs) are a recurrent phenomenon in the Northeast Pacific, with duration greatly affected by tropical interactions and intensity primarily stemming from the extratropics. The 2013-2015 Northeast Pacific MHW was an extreme example of this phenomenon that may have been further strengthened by climate change.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Environmental Sciences
Tarang Khangaonkar, Adi Nugraha, Su Kyong Yun, Lakshitha Premathilake, Julie E. Keister, Julia Bos
Summary: The study on the effects of the Northeast Pacific marine heatwave of 2014-2016 on the Salish Sea estuarine waters revealed that while higher temperatures led to increased biological activity, it was primarily due to increased freshwater and nutrient loads rather than warming from the heatwave itself. Strong vertical circulation and mixing helped mitigate temperature increases, keeping the waters cooler relative to the continental shelf during the marine heatwave.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Limnology
Pierre Marrec, Heather McNair, Gayantonia Franze, Francoise Morison, Jacob P. Strock, Susanne Menden-Deuer
Summary: This study analyzed data from winter and summer cruises as part of the Northeast U.S. Shelf Long-Term Ecological Research program and found that coastal waters had higher phytoplankton biomass dominated by large cells in winter and small cells in summer. Phytoplankton growth rates were correlated with temperature, light availability, and community size-structure, while grazing rates were not correlated with total chlorophyll a, indicating other biological drivers at play in predator-prey interactions at the first trophic level.
LIMNOLOGY AND OCEANOGRAPHY
(2021)
Article
Geography, Physical
Michael J. Bentley, James A. Smith, Stewart S. R. Jamieson, Margaret R. Lindeman, Brice R. Rea, Angelika Humbert, Timothy P. Lane, Christopher M. Darvill, Jeremy M. Lloyd, Fiamma Straneo, Veit Helm, David H. Roberts
Summary: The Northeast Greenland Ice Stream has experienced significant change in its floating margins and is now vulnerable to future climate warming. A study has provided direct evidence of warm Atlantic Intermediate Water (AIW) being present near the grounding line of the 79 degrees N Glacier, over 50 km from the calving front. This suggests that offshore oceanographic changes can rapidly affect the stability of the ice stream.
Article
Environmental Sciences
Indah Ardiningsih, Kechen Zhu, Pablo Lodeiro, Martha Gledhill, Gert-Jan Reichart, Eric P. Achterberg, Rob Middag, Loes J. A. Gerringa
Summary: Competitive ligand exchange - adsorptive cathodic stripping voltammetry (CLE-AdCSV) is a widely used technique for determining dissolved iron (Fe) speciation in seawater. The comparison of total ligand concentrations and conditional stability constants obtained using different added ligands (ALs) showed differences among measurement results in different marine areas, indicating the influence of different ligand types on the results.
FRONTIERS IN MARINE SCIENCE
(2021)
Article
Biodiversity Conservation
Mads Reinholdt Jensen, Signe Hogslund, Steen Wilhelm Knudsen, Julius Nielsen, Peter Rask Moller, Soren Rysgaard, Philip Francis Thomsen
Summary: The study aims to investigate the transition in fish and marine mammal communities from South to Northeast Greenland using environmental DNA (eDNA). The results demonstrate a clear shift in biological communities from south to northeast, with different fish and mammal species dominating each region. The study highlights the potential of eDNA sampling in detecting latitudinal changes in marine biological communities and its feasibility in remote areas as climate change progresses.
DIVERSITY AND DISTRIBUTIONS
(2023)
Article
Environmental Sciences
Henry C. Henson, Johnna M. Holding, Lorenz Meire, Soren Rysgaard, Colin A. Stedmon, Alice Stuart-Lee, Jorgen Bendtsen, Mikael Sejr
Summary: Greenland's fjords and coastal waters are highly productive and sustain important fisheries, but retreating glaciers and increasing meltwater are changing fjord circulation and biogeochemistry, potentially threatening future productivity. The freshening of Greenland fjords caused by unprecedented melting of the Greenland Ice Sheet may alter carbonate chemistry in coastal waters, impacting CO2 uptake and causing acidification-related biological consequences. However, there have been few studies on the current acidification state in Greenland coastal waters.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Limnology
Anders Dalhoff Bruhn, Urban Wunsch, Christopher L. Osburn, Jacob C. Rudolph, Colin A. Stedmon
Summary: Analysis of lignin in seawater is crucial for understanding the behavior of terrestrial dissolved organic matter (DOM) in the ocean and its role in the carbon cycle. An improved method using liquid chromatography (LC) and absorbance detection is presented, which effectively quantifies lignin phenols with improved sensitivity and specificity compared to manual integration methods. The method achieves detection limits below 5 nmol L-1 for most lignin phenols and demonstrates good reproducibility. Application of the method to seawater samples confirms the potential of LC and absorbance detection for analysis of dissolved lignin.
LIMNOLOGY AND OCEANOGRAPHY-METHODS
(2023)
Article
Engineering, Environmental
Mathis von Ahnen, Colin A. Stedmon, Adam C. Hambly
Summary: The study investigated whether foam fractionators could effectively reduce the leaching of dissolved organic matter from woodchip bioreactors during start-up. The results showed that foam fractionation removed 37.8 +/- 4.7% of the dissolved chemical oxygen demand (CODdiss) filtered by the bioreactors during the first 11 days of operation, thus reducing their environmental impact.
WATER SCIENCE AND TECHNOLOGY
(2023)
Article
Oceanography
S. E. L. Howell, D. G. Babb, J. C. Landy, G. W. K. Moore, B. Montpetit, M. Brady
Summary: This study compares and analyzes the sea ice area and volume fluxes of Nares Strait and the Canadian Arctic Archipelago. The results show that Nares Strait has the largest ice flux, followed by the Queen Elizabeth Islands and M'Clure Strait. The majority of ice export comes from Nares Strait, with the highest fluxes observed in 2017-2019 and 2021, but remarkably exceeded by the Queen Elizabeth Islands in 2020. It is predicted that under continued warming, the ice export from Nares Strait and the Queen Elizabeth Islands will increase.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2023)
Article
Oceanography
T. M. Burgers, L. A. Miller, S. Rysgaard, J. Mortensen, B. Else, J. -E Tremblay, T. Papakyriakou
Summary: In August 2014, we characterized the physico-chemical properties of water masses entering Nares Strait. We used an extended OMP analysis to estimate mixing fractions and determine the role of physical and biological processes in the distribution of DIC. Our observations include evidence of Siberian shelf waters and diluted Pacific-origin upper halocline layer entering Nares Strait. These mixed-origin water masses drive phytoplankton bloom in Kane Basin, leading to decreased surface pCO(2) concentrations. The positioning of the Transpolar Drift and the balance of Atlantic and Pacific water delivered to Nares Strait play an important role in regional biological productivity and carbon uptake.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2023)
Article
Geochemistry & Geophysics
Gang Lin, Jixin Qiao, Paul A. Dodd, Rafael Goncalves-Araujo, Mats A. Granskog, Peter Steier, Colin A. Stedmon
Summary: This study demonstrates the improvement in estimating the transit times of different Atlantic water pathways in the Arctic Ocean by combining measurements of CDOM with U-236(NRPs).
EARTH AND PLANETARY SCIENCE LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Rafael Goncalves-Araujo, Mats A. Granskog, Christopher L. Osburn, Piotr Kowalczuk, Colin A. Stedmon
Summary: This study presents a simple and feasible method for estimating DOC concentrations in Arctic waters using CDOM absorption spectroscopy. The algorithm accurately reproduces DOC profiles and mixing plots at different locations, capturing the DOC concentration gradient between Arctic riverine and marine systems.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Environmental Sciences
Andreas Libonati Brock, Kristin Kostadinova, Emma Mork-Pedersen, Fides Hensel, Yifeng Zhang, Borja Valverde-Perez, Colin A. Stedmon, Stefan Trapp
Summary: Marine dead zones, caused by hypoxia, have been expanding and threatening coastal marine life. In order to protect the marine environment from the formation of dead zones, sediment microbial fuel cells (SMFCs) were tested for their ability to reduce the release of sulfide from sediments. The study found that both steel electrodes and charcoal-amended electrodes could effectively reduce sulfide concentrations in bottom water, as well as phosphate concentrations and ammonium.
MARINE POLLUTION BULLETIN
(2023)
Article
Oceanography
D. G. Babb, R. J. Galley, S. Kirillov, J. C. Landy, S. E. L. Howell, J. C. Stroeve, W. Meier, J. K. Ehn, D. G. Barber
Summary: The loss of multiyear sea ice in the Arctic Ocean has occurred primarily through two stepwise reductions: in 1989 and in 2006-2008. The first reduction was due to high export of multiyear ice, while the second reduction was a result of both high export and melt, as well as limited replenishment of multiyear ice. Although currently stable, reduced retention of older multiyear ice has led to a younger and thinner multiyear ice pack, potentially setting the stage for another reduction.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2023)
Article
Remote Sensing
Dustin Isleifson, Madison L. Harasyn, David Landry, David Babb, Elvis Asihene
Summary: This study addresses the accurate interpretation of satellite images of Arctic sea ice through a focused remote sensing study. The results quantify the sensitivity of different sensors to the presence of frost flowers, snow, and meteorological conditions. Furthermore, drone surveys enhance the characterization of the ice by bridging the gap between surface-based sensing and satellite imagery.
CANADIAN JOURNAL OF REMOTE SENSING
(2023)
Article
Geosciences, Multidisciplinary
Martine Lizotte, Bennet Juhls, Atsushi Matsuoka, Philippe Massicotte, Gaelle Mevel, David Obie James Anikina, Sofia Antonova, Guislain Becu, Marine Beguin, Simon Belanger, Thomas Bosse-Demers, Lisa Broeder, Flavienne Bruyant, Gwenaelle Chaillou, Jerome Comte, Raoul-Marie Couture, Emmanuel Devred, Gabriele Deslongchamps, Thibaud Dezutter, Miles Dillon, David Doxaran, Aude Flamand, Frank Fell, Joannie Ferland, Marie-Helene Forget, Michael Fritz, Thomas J. Gordon, Caroline Guilmette, Andrea Hilborn, Rachel Hussherr, Charlotte Irish, Fabien Joux, Lauren Kipp, Audrey Laberge-Carignan, Hugues Lantuit, Edouard Leymarie, Antonio Mannino, Juliette Maury, Paul Overduin, Laurent Oziel, Colin Stedmon, Crystal Thomas, Lucas Tisserand, Jean-Eric Tremblay, Jorien Vonk, Dustin Whalen, Marcel Babin
Summary: Climate warming in the Arctic is expected to change the distribution and dynamics of carbon in frozen grounds. Thawing permafrost in the Mackenzie River watershed releases organic matter into the Arctic Ocean, but its fate remains poorly understood. Field expeditions were conducted to study this process in the Mackenzie Delta region and southern Beaufort Sea, with the collaboration of local communities and the measurement of various physical, chemical, and biological variables.
EARTH SYSTEM SCIENCE DATA
(2023)
Article
Remote Sensing
Kaushik Gupta, Jens K. Ehn
Summary: This study investigates whether snow melt on land adjacent to the coast can serve as a precursor to landfast ice break-up, and finds a significant correlation between snowmelt timing and landfast ice break-up dates.
CANADIAN JOURNAL OF REMOTE SENSING
(2023)