Climate change and terrigenous inputs decrease the efficiency of the future Arctic Ocean’s biological carbon pump

Nature Climate Change, Journal Year: 2025, Volume and Issue: 15(2), P. 171 - 179

Published: Jan. 6, 2025

Abstract The Arctic experiences climate changes that are among the fastest in world and affect all Earth system components. Despite expected increase terrigenous inputs to Ocean, their impacts on biogeochemical cycles currently largely neglected IPCC-like models. Here we used a state-of-the-art high-resolution ocean biogeochemistry model includes carbon nutrient from rivers coastal erosion produce twenty-first-century pan-Arctic projections. Surprisingly, even with an anticipated rise primary production across wide range of emission scenarios, our findings indicate change will lead counterintuitive 40% reduction efficiency Arctic’s biological pump by 2100, which contribute 10%. Terrigenous also drive intense CO 2 outgassing, reducing Ocean’s sink at least 10% (33 TgC yr −1 ). These unexpected reinforced feedback, mostly due accelerated remineralization rates, lower capacity for sequestering carbon.

Language: Английский

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A Review of Arctic–Subarctic Ocean Linkages: Past Changes, Mechanisms, and Future Projections

Ocean-Land-Atmosphere Research, Journal Year: 2023, Volume and Issue: 2

Published: Jan. 1, 2023

Arctic Ocean gateway fluxes play a crucial role in linking the with global ocean and affecting climate marine ecosystems. We reviewed past studies on Arctic–Subarctic linkages examined their changes driving mechanisms. Our review highlights that radical occurred inflows outflows of during 2010s. Specifically, Pacific inflow temperature Bering Strait Atlantic Fram hit record highs, while salinity outflow Davis straits lows. Both heat convergence from lower latitudes to hydrological cycle connecting Subarctic seas were stronger 2000–2020 than 1980–2000. CMIP6 models project continuing increase poleward 21st century, mainly due warming waters. They also predict an freshwater input Ocean, largest export expected occur both increased volume decreased salinity. sea ice low 2010s is projected continue decrease along decline. quantitatively attribute variability volume, heat, transports gateways forcing within outside based dedicated numerical simulations emphasize importance origins variability.

Language: Английский

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Climate tipping point interactions and cascades: A review

Published: Aug. 1, 2023

Abstract. Climate tipping elements are large-scale subsystems of the Earth that may transgress critical thresholds (tipping points) under ongoing global warming, with substantial impacts on biosphere and human societies. Frequently studied examples such include Greenland Ice Sheet, Atlantic Meridional Overturning Circulation, permafrost, monsoon systems, Amazon rainforest. While recent scientific efforts have improved our knowledge about individual elements, interactions between them less well understood. Also, potential events to induce additional elsewhere, or stabilize other is largely unknown. Here, we map out current state literature climate review influences them. To do so, gathered evidence from model simulations, observations conceptual understanding, as archetypal paleoclimate reconstructions where multi-component spatially propagating transitions were potentially at play. Lastly, identify crucial gaps in element outline how future research could address those gaps.

Language: Английский

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An Assessment of CO₂ Uptake in the Arctic Ocean From 1985 to 2018

Global Biogeochemical Cycles, Journal Year: 2023, Volume and Issue: 37(11)

Published: Nov. 1, 2023

Abstract As a contribution to the Regional Carbon Cycle Assessment and Processes phase 2 (RECCAP2) project, we present synthesized estimates of Arctic Ocean sea‐air CO fluxes their uncertainties from surface ocean p ‐observation products, biogeochemical hindcast data assimilation models, atmospheric inversions. For period 1985–2018, was net sink 116 ± 4 TgC yr −1 in 92 30 91 21 The uptake peaks late summer early autumn, is low winter when sea ice inhibits fluxes. long‐term mean primarily caused by steady‐state natural carbon (70% 15%), enhanced increase (19% 5%) climate change (11% 18%). annual increased 1985 2018 at rate 31 13 dec 10 32 16 Moreover, 77% 38% trend over time change, due rapid loss recent years. Furthermore, true may be larger than given ensemble standard deviations common structural biases across all individual estimates.

Language: Английский

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Seafloor primary production in a changing Arctic Ocean

Proceedings of the National Academy of Sciences, Journal Year: 2024, Volume and Issue: 121(11)

Published: March 4, 2024

Phytoplankton and sea ice algae are traditionally considered to be the main primary producers in Arctic Ocean. In this Perspective, we explore importance of benthic (BPPs) encompassing microalgae, macroalgae, seagrasses, which represent a poorly quantified source marine production. Despite scarce observations, models predict that BPPs widespread, colonizing ~3 million km 2 extensive coastal shelf seas. Using synthesis published data novel model, estimate currently contribute ~77 Tg C y −1 production Arctic, equivalent ~20 35% annual phytoplankton Macroalgae ~43 , seagrasses ~23 microalgae-dominated habitats ~11 16 . Since 2003, seafloor area exposed sunlight has increased by ~47,000 expanding realm warming Arctic. Increased macrophyte abundance productivity is expected along coastlines with continued ocean loss. However, microalgal only few regions despite substantial loss over past 20 y, as higher solar irradiance ice-free counterbalanced reduced water transparency. This suggests complex impacts climate change on light availability significant knowledge gaps BPPs, their widespread presence obvious contribution ecosystem call for further investigation inclusion carbon budgets.

Language: Английский

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Carbon dioxide sink in the Arctic Ocean from cross-shelf transport of dense Barents Sea water

Nature Geoscience, Journal Year: 2022, Volume and Issue: 16(1), P. 82 - 88

Published: Nov. 21, 2022

Abstract Large amounts of atmospheric carbon can be exported and retained in the deep sea on millennial time scales, buffering global warming. However, while Barents Sea is one most biologically productive areas Arctic Ocean, retention times were thought to short. Here we present observations, complemented by numerical model simulations, that revealed a widespread lateral injection approximately 2.33 kt C d −1 from shelf some 1,200 m Nansen Basin, driven Bottom Water transport. With increasing distance outflow region, plume expanded penetrated into even deeper waters sediment. The seasonally fluctuating but continuous increases sequestration 1/3 feeds community Basin. Our findings combined with those other regions carbon-rich polar dense highlight importance as sink. Resolving uncertainties around negative feedbacks warming due ice decline will necessitate observation changes bottom water formation biological productivity at resolution high enough quantify future injection.

Language: Английский

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Ocean biogeochemistry in the coupled ocean–sea ice–biogeochemistry model FESOM2.1–REcoM3

Geoscientific model development, Journal Year: 2023, Volume and Issue: 16(16), P. 4883 - 4936

Published: Aug. 30, 2023

Abstract. The cycling of carbon in the oceans is affected by feedbacks driven changes climate and atmospheric CO2. Understanding these therefore an important prerequisite for projecting future climate. Marine biogeochemistry models are a useful tool but, as with any model, simplification need to be continually improved. In this study, we coupled Finite-volumE Sea ice–Ocean Model (FESOM2.1) Regulated Ecosystem version 3 (REcoM3). FESOM2.1 update Finite-Element (FESOM1.4) operates on unstructured meshes. Unlike standard structured-mesh ocean models, mesh flexibility allows realistic representation small-scale dynamics key regions at affordable computational cost. Compared previous model FESOM1.4–REcoM2, FESOM2.1–REcoM3 utilizes new dynamical core, based finite-volume discretization instead finite elements, retains central parts model. As feature, carbonate chemistry, including water vapour correction, computed mocsy 2.0. Moreover, REcoM3 has extended food web that includes macrozooplankton fast-sinking detritus. Dissolved oxygen also added tracer. assess biogeochemical state simulated global set-up relatively low spatial resolution forced JRA55-do (Tsujino et al., 2018) reanalysis. focus recent period (1958–2021) how well can used present-day change scenarios decadal centennial timescales. A bias ocean–atmosphere preindustrial CO2 flux present (FESOM1.4–REcoM2) could significantly reduced. addition, efficiency 2–3 times higher than FESOM1.4–REcoM2. Overall, it found skilful modelling applications.

Language: Английский

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Modeling the Recent Changes of Phytoplankton Blooms Dynamics in the Arctic Ocean

Journal of Geophysical Research Oceans, Journal Year: 2023, Volume and Issue: 128(6)

Published: May 10, 2023

Abstract In recent decades, Arctic Ocean (AO) sea ice has experienced intense climate‐related modifications, which coincide with earlier melting in spring and delayed formation the fall. this study, we use ECCO2‐Darwin ocean biogeochemistry model to gain a mechanistic understanding of how changes sea‐ice seasonality impact phenology AO phytoplankton blooms. We 2006–2013 simulation show that early melt 2007 2012 triggers blooms (∼1 month compared other years) dissipate due more rapid nutrient depletion surface AO. Our also confirms during fall second blooms, agreement observations. These results suggest warmer changing climate, further extent could drastically phytoplankton, important consequences for marine ecosystems.

Language: Английский

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Longer Ice‐Free Conditions and Increased Run‐Off From the Ice Sheet Will Impact Primary Production in Young Sound, Greenland

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

Published: April 30, 2025

Abstract The Arctic coastal ocean is among the habitats most impacted by climate change due to cumulative impact of several interacting drivers. high‐Arctic Young Sound in north‐east Greenland characterized a short ice‐free period (July–October). system influenced high run‐off, mainly from glacial meltwater during summer (June–September) affecting turbidity. Our analysis showed that has experienced longer without sea ice since 1950 global warming and increased run‐off melting land‐terminating glaciers. We applied 3D ecosystem model for estimate present‐day primary production potential future (25 50 years) different scenarios periods run‐off. light was improved including suspended particulate matter (SPM) released with freshwater sources. A shorter coverage gave an increase annual productive season model. Increased found decrease more attenuation SPM. However, spatial displacement observed water column between areas changes nutrient availability. When higher were combined, modest overall except deep layer suffering stronger limitation. present study can contribute better understanding generalization productivity fjords.

Language: Английский

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Implications of climate change on biogeochemical cycles in the Arctic Ocean with special emphasis on the nitrogen cycle

Polar Biology, Journal Year: 2025, Volume and Issue: 48(2)

Published: May 14, 2025

Language: Английский

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