Complexity of Arctic Ocean water isotope (δ18O, δ2H) spatial and temporal patterns revealed with machine learning DOI Creative Commons
E. S. Klein, Andrew P. Baltensperger, J. M. Welker

et al.

Elementa Science of the Anthropocene, Journal Year: 2024, Volume and Issue: 12(1)

Published: Jan. 1, 2024

The stable isotope compositions of water (δ18O, δ2H, deuterium-excess) are important tracers that help illuminate the changing Arctic cycle and how Arctic-sourced can influence lower latitudes. We present simultaneous boundary layer vapor ocean data were measured continuously in western Ocean. Sea surface isotopes varied between shallower continental Chukchi Shelf deeper Borderlands to north. waters less saline than offshore Shelf, as influenced by greater sea ice cover contribution melt freshwater. This resulted deuterium-excess (δ2H − 8*δ18O) values on Shelf. Additionally, contributions freshwater prominent river runoff, but from both sources decreased substantially below 70 m depth Borderlands. Our observed provided foundation for producing maps (isoscapes) based remote sensing machine learning which incorporate parameters circulation thus (e.g., salinity, temperature, depth). These isoscapes suggest spatial complexity distribution Arctic, including sharp gradients seawater studied. be improved future iterations, example, with availability more spatially continuous, remotely sensed oceanic variables or continuous ship-based measurements use additional predictors. As a result, generation these could become useful tool understanding past, present, context global hydrologic cycle.

Language: Английский

Biomarker proxies for reconstructing Quaternary climate and environmental change DOI Creative Commons
Erin L. McClymont, Helen Mackay, Mark A. Stevenson

et al.

Journal of Quaternary Science, Journal Year: 2023, Volume and Issue: 38(7), P. 991 - 1024

Published: Aug. 23, 2023

ABSTRACT To reconstruct past environmental changes, a range of indirect or proxy approaches can be applied to Quaternary archives. Here, we review the complementary and novel insights that have been provided by analysis chemical fossils (biomarkers). Biomarkers biological source highly specific (e.g. produced small group organisms) more general. We show biomarkers are able quantify key climate variables (particularly water air temperature) provide qualitative evidence for changes in hydrology, vegetation, human–environment interactions biogeochemical cycling. In many settings, biomarker proxies opportunity simultaneously multiple variables, alongside long‐established palaeoenvironmental reconstruction. Multi‐proxy studies rich sets data explore both drivers impacts change. As new continue developed refined, there is further potential answer emerging questions science

Language: Английский

Citations

12
Phytoplankton diversity and zooplankton diet across Fram Strait: Spatial patterns with implications for the future Arctic Ocean DOI Creative Commons
Patricia Kaiser, Wilhelm Hagen, Anna Schukat

et al.

Progress In Oceanography, Journal Year: 2025, Volume and Issue: unknown, P. 103423 - 103423

Published: Feb. 1, 2025

Language: Английский

Citations

0
Key drivers of large scale changes in North Atlantic atmospheric and oceanic circulations and their predictability DOI Creative Commons
Buwen Dong, Yevgeny Aksenov, Ioana Colfescu

et al.

Climate Dynamics, Journal Year: 2025, Volume and Issue: 63(2)

Published: Feb. 1, 2025

Significant changes have occurred during the last few decades across North Atlantic climate system, including in atmosphere, ocean, and cryosphere. These large-scale play a vital role shaping regional extreme weather events UK Western Europe. This review synthesizes characteristics of observed atmospheric oceanic circulations past decades, identifies drivers physical processes responsible for these changes, outlines projected due to anthropogenic warming, discusses predictability circulations. On multi-decadal time scales, internal variability, forcings (especially greenhouse gases), natural (such as solar variability volcanic eruptions) are identified key contributors However, there remain many uncertainties regarding detailed various influences, some cases their relative importance. We therefore conclude that better understanding drivers, more accurate quantification roles, crucial reliable decadal predictions projections The online version contains supplementary material available at 10.1007/s00382-025-07591-1.

Language: Английский

Citations

0
A decade of reproductive abnormalities in pelagic ostracods observed at the entrance to a changing Arctic DOI Creative Commons
Emily Y. Chen, Emilia Trudnowska, Anette Wold

et al.

Marine Biology, Journal Year: 2025, Volume and Issue: 172(3)

Published: Feb. 7, 2025

Abstract The rapid warming of the Arctic Ocean is driving significant shifts in ecosystem dyamics, from species-level morphological changes to community composition. Within pelagic community, Ostracoda an understudied zooplankton group that exhibits distinct sexually dimorphic features, including carapace shape, size, frontal and reproductive organs, antennae. During analyses a time series collected each summer 2010 2019 Fram Strait, main gateway between north Atlantic Ocean, all four dominant ostracod species ( Boroecia maxima , B. borealis Discoconchoecia elegans Obtusoecia obtusata ) displayed abnormalities form pseudopenises otherwise had female features. Out total analyzed material 4,137 adult pre-mature A-1 stages individuals, 646 stage or 15.6% population, exhibited pseudopenises. All observed were confined with no variant adults recorded. primary difference these normal male penises was lack muscle bands sperm duct required for functionality. However, few females signs ducts developing, suggesting potential transition true intersexuality. Monitoring this phenomenon ostracods crucial because it can have population-wide consequences. Furthermore, widespread intersexuality could complicate interpretation ecological trends changing Arctic.

Language: Английский

Citations

0
FORAMINIFERAL CARBONATE PRODUCTION DECREASE IN A RAPIDLY CHANGING FJORD (HORNSUND, SVALBARD 2002–2019) DOI
Natalia Szymańska, Manjulesh Pai, Dhanushka Devendra

et al.

The Journal of Foraminiferal Research, Journal Year: 2025, Volume and Issue: 55(2), P. 144 - 159

Published: April 1, 2025

ABSTRACT Fjords are critical carbon burial hotspots, playing a significant role in climate regulation. However, the impact of current change on foraminifera Arctic fjords remains underexplored, despite foraminiferal inorganic carbon’s substantial contribution to glaciomarine sediments form calcium carbonate. This study investigates how benthic assemblages high-latitude fjord responded recent climatic shifts terms abundance and species composition between 2002 2019. The environmental changes have reduced number tests produced by foraminifera, shifted towards smaller species, increased agglutinated specimens sediments. These factors contributed an over tenfold decline carbonate 2019 compared those from 2002, providing evidence change’s at this location.

Language: Английский

Citations

0
Paleoceanographic changes along the western Spitsbergen margin, evidence from planktic microfossil during the last 10 kyr BP DOI
Fiorenza Torricella, Caterina Morigi, Viviana María Gamboa-Sojo

et al.

Palaeogeography Palaeoclimatology Palaeoecology, Journal Year: 2025, Volume and Issue: unknown, P. 112940 - 112940

Published: April 1, 2025

Language: Английский

Citations

0
Changes in the Coastal Wind Field and River Runoff Conditions Expose Kongsfjorden (Svalbard) to the Influence of Atlantic Water DOI Creative Commons
Francesco De Rovere, Jacopo Chiggiato, Leonardo Langone

et al.

Journal of Geophysical Research Oceans, Journal Year: 2025, Volume and Issue: 130(5)

Published: May 1, 2025

Abstract Kongsfjorden is located in West Spitsbergen, Svalbard archipelago. Its hydrography influenced by the Spitsbergen Current (WSC) transporting warm and saline Atlantic Water (AW) toward Arctic basin. We assessed changes fjord water properties over two decades (1999–2020) using summer hydrographic surveys performed Norwegian Polar Institute fjord, adjacent shelf, open ocean regions. The heat content (HC) salinity within have increased driven a larger inflow of AW. These trends are consistent with observations neighboring Isfjorden but not mirrored WSC same timeframe. Therefore, these fjords can be attributed to AW intrusions rather than variations upstream properties. hypothesize that HC shifts synoptic wind patterns glacier meltwater release enhancing shelf exchanges. Idealized modeling experiments revealed although modifications contribute increasing fjord's HC, they explain only small portion observed changes, suggesting availability on dominant factor.

Language: Английский

Citations

0
Marine Plankton during the Polar Night: Environmental Predictors of Spatial Variability DOI Creative Commons
Vladimir G. Dvoretsky, M. P. Venger, A. V. Vashchenko

et al.

Biology, Journal Year: 2023, Volume and Issue: 12(3), P. 368 - 368

Published: Feb. 25, 2023

We studied the spatial patterns of planktonic ecosystems at two Arctic sites strongly affected by Atlantic Inflow (FS, Fram Strait; and BS, Barents Sea). A high degree similarity in bacterial abundance (mean: 3.1 × 105 cells mL−1 FS vs. 3.5 BS) was found, while other plankton characteristics were different. Bacterial biomass reached a maximum BS (3.2–7.9 mg C m−3), viral abundances tended to be higher (2.0–5.7 106 particles mL−1). Larger found suggesting presence different populations both locations. The virus-to-bacteria ratio significantly than (13.5 4.7). Chlorophyll concentration extremely low (<0.25 m−3). highest zooplankton surface layer (919 individuals m−3 602 ind. BS). Zooplankton varied (1–39 with BS. High proportions boreal taxa total indicate Atlantification pelagic Arctic. Plankton indicators are correlated temperature, salinity, sampling depth. Strong intercorrelations between major groups, tight links ecosystems.

Language: Английский

Citations

8
Climate change dynamics and mercury temporal trends in Northeast Arctic cod (Gadus morhua) from the Barents Sea ecosystem DOI Creative Commons
Michael S. Bank, Quang Tri Ho, Randi Ingvaldsen

et al.

Environmental Pollution, Journal Year: 2023, Volume and Issue: 338, P. 122706 - 122706

Published: Oct. 9, 2023

The Northeast Arctic cod (Gadus morhua) is the world's northernmost stock of Atlantic and considerable ecological economic importance. are widely distributed in Barents Sea, an environment that supports a high degree ecosystem resiliency food web complexity. Here using 121 years ocean temperature data (1900-2020), 41 sea ice extent information (1979-2020) 27 total mercury (Hg) fillet concentration (1994-2021, n = 1999, ≥71% Methyl Hg, 20) from Sea ecosystem, we evaluate effects climate change dynamics on Hg temporal trends cod. We observed low consistently stable, concentrations (yearly, least-square means range 0.022-0.037 mg/kg wet wt.) length-normalized fish, with slight decline most recent sampling periods despite significant increase temperature, sharp regional extent. Overall, our suggest amplification "Atlantification," other perturbations along rapidly declining over last ∼30 did not translate into major increases or decreases bioaccumulation Our findings consistent similar long-term, assessments inhabiting Oslofjord, Norway, investigations empirical for marine apex predators. This demonstrates highly context specific, some species may be as sensitive to current change-contaminant interactions currently thought. Fish bioaccumulation-climate relationships complex uniform, predators can vary considerably within among species, geographically. regimes biota nuanced likely driven by suite factors such local diets, sources bioenergetics, toxicokinetic processing, growth metabolic rates individuals taxa, inputs anthropogenic activities at varying spatiotemporal scales. Collectively, these have important policy implications global security, Minamata Convention Mercury, several relevant UN Sustainable Development Goals.

Language: Английский

Citations

8
The Northeast Water Polynya, Greenland: Climatology, Atmospheric Forcing and Ocean Response DOI Creative Commons
Miriam Bennett, Ian A. Renfrew, David P. Stevens

et al.

Journal of Geophysical Research Oceans, Journal Year: 2024, Volume and Issue: 129(5)

Published: May 1, 2024

Abstract The Northeast Water Polynya is a significant annually recurring summertime Arctic polynya, located off the coast of Greenland. It important for marine wildlife and affects local atmospheric oceanic processes. In this study, over 40 years observational reanalysis products (ERA5 ORAS5) are analyzed to characterize polynya's climatology ascertain forcing mechanisms. has high spatiotemporal variability; its location, size structure vary interannually, period which it open changing. We show variability largely driven by forcing. polynya extent determined direction near‐surface flow regime, relative locations low sea‐level pressure centers region. surface conditions also impact water column, strong seasonal cycle in potential temperature salinity, amplitude decreases with depth. ocean reanalyses warming trend at all depths freshening near consistent greater ice melt, but salinification lower (∼200 m). As region changes due anthropogenic forcing, sea‐ice edge migrating northwards generally opening earlier closing later year. This could have implications both atmosphere complex rapidly changing environment.

Language: Английский

Citations

3