Acidification of East Siberian Arctic Shelf waters through addition of freshwater and terrestrial carbon

Semiletov, I. P.; Pipko, I. I.; Gustafsson, Örjan; Anderson, Leif G.; Сергиенко, В. И.; Pugach, S. P.; Dudarev, Oleg V.; Charkin, Alexander; Gukov, Alexander; Bröder, Lisa; Andersson, August; Spivak, Eduard; Shakhova, Natalia

doi:10.1038/ngeo2695

Cited by 173 publications

(163 citation statements)

References 44 publications

Supporting

Mentioning

153

Contrasting

Unclassified

Order By: Relevance

“…opinion & comment mineralization of organic carbon in the water might also strengthen ongoing ocean acidification 15 , leading to conditions in which some carbonate species essential to the coastal food web will not survive (Fig. 1).…”

Section: Yves Nowak / Michael Fritzmentioning

confidence: 99%

Collapsing Arctic coastlines

2017

View full text Add to dashboard Cite

A holistic and transdisciplinary approach is urgently required to investigate the physical and socio-economic impacts of collapsing coastlines in the Arctic nearshore zone.A rctic permafrost coasts account for 34% of Earth's coasts 1 . Coastal erosion rates as high as 25 m yr -1 (refs 2,3) together with the large amount of organic matter frozen in permafrost 4,5 are resulting in an annual release of 14.0 Tg (10 12 grams) of particulate organic carbon into the nearshore zone 6,7 . This carbon flux is in the same order of magnitude as the yearly contribution from all Arctic rivers, or the vertical net methane (CH 4 ) emissions from terrestrial permafrost 8 . Arctic nearshore zones (shallower than 20 m water depth) represent about 20% of the shelves and 7.5% of the Arctic Ocean -a much greater proportion than for the rest of the Earth, where the nearshore zone occupies only 1.4% of the world's ocean area 9,10 . Rapid environmental changes that occur in the Arctic nearshore zone are systematically under-studied, because icebreaking research vessels avoid these shallow waters, and there is very limited shore-based research infrastructure. However, this zone is the primary recipient of increasing fluxes of carbon and nutrients from thawing permafrost. We highlight the crucial role the nearshore zone plays in Arctic biogeochemical cycling, as the fate of the released material is determined in this location. It may (i) degrade into greenhouse gases, (ii) fuel marine primary production, (iii) be buried in nearshore sediments or (iv) be transported offshore (Fig. 1).Fluxes from coastal erosion are expected to drastically increase due to the combined effect of declining summer sea-ice cover on the Arctic Ocean, longer and warmer thawing seasons, and the rising sea level allowing waves to hit the coast higher and longer during the ice-free season. Unlike large rivers, where decadal to centennial discharge fluctuations can be constrained to a ±10% window 11,12 , coastal erosion fluxes have the potential to increase by an order of magnitude on the same timescale 13 . Such increases would result in drastic impacts on global carbon fluxes and their climate feedbacks, on nearshore food webs, and on local communities, whose survival still relies on marine biological resources. Environment and societyCurrently, most Arctic research is focused on permafrost in tundra and boreal landscapes and on the potential vertical greenhouse gas fluxes resulting from gradual permafrost thaw 4 . Although emission scenarios from gradual permafrost carbon degradation are urgently needed to better constrain Earth system models, impacts of accelerating coastal erosion on nearshore ecosystems are immediate and irreversible. Arctic warming and sea level rise account for the observed coastline collapse as an abrupt form of permafrost degradation that leads to the rapid release of large amounts of previously frozen organic carbon to the nearshore zone. The fate of this permafrost carbon, however, has never been properly quantified. Eroding coasts will ...

show abstract

Section: Yves Nowak / Michael Fritzmentioning

confidence: 99%

Collapsing Arctic coastlines

2017

View full text Add to dashboard Cite

show abstract

“…This likely is the first formal description of what today is known as the Arctic amplification, i.e., a higher temperature increase in Arctic regions than in other regions of the globe (Serreze and Barry, 2011;Jeffries et al, 2013). The changes being observed today will probably become more intense in the coming decades through positive feedback, causing further changes in atmospheric circulation, river discharge, the carbon cycle, vegetation, conditions of terrestrial and submarine permafrost, and many other natural processes; the consequences will be noticed within, as well as outside of, the Arctic region (Serreze and Barry, 2011;Anderson et al, 1998;Macdonald et al, 2008;Semiletov et al, 2000Semiletov et al, , 2016Shakhova et al, 2014). Currently, these changes refer to a "new condition" of the Arctic climate (Kattsov et al, 2010;Jeffries et al, 2013;Wood et al, 2015).…”

Section: Introductionmentioning

confidence: 99%

The spatial and interannual dynamics of the surface water carbonate system and air–sea CO<sub>2</sub> fluxes in the outer shelf and slope of the Eurasian Arctic Ocean

et al. 2017

Self Cite

View full text Add to dashboard Cite

Abstract. The Arctic is undergoing dramatic changes which cover the entire range of natural processes, from extreme increases in the temperatures of air, soil, and water, to changes in the cryosphere, the biodiversity of Arctic waters, and land vegetation. Small changes in the largest marine carbon pool, the dissolved inorganic carbon pool, can have a profound impact on the carbon dioxide (CO 2 ) flux between the ocean and the atmosphere, and the feedback of this flux to climate. Knowledge of relevant processes in the Arctic seas improves the evaluation and projection of carbon cycle dynamics under current conditions of rapid climate change.Investigation of the CO 2 system in the outer shelf and continental slope waters of the Eurasian Arctic seas (the Barents, Kara, Laptev, and East Siberian seas) during 2006, 2007, and 2009 revealed a general trend in the surface water partial pressure of CO 2 (pCO 2 ) distribution, which manifested as an increase in pCO 2 values eastward. The existence of this trend was defined by different oceanographic and biogeochemical regimes in the western and eastern parts of the study area; the trend is likely increasing due to a combination of factors determined by contemporary change in the Arctic climate, each change in turn evoking a series of synergistic effects. A high-resolution in situ investigation of the carbonate system parameters of the four Arctic seas was carried out in the warm season of 2007; this year was characterized by the next-to-lowest historic sea-ice extent in the Arctic Ocean, on satellite record, to that date. The study showed the different responses of the seawater carbonate system to the environment changes in the western vs. the eastern Eurasian Arctic seas. The large, open, highly productive water area in the northern Barents Sea enhances atmospheric CO 2 uptake. In contrast, the uptake of CO 2 was strongly weakened in the outer shelf and slope waters of the East Siberian Arctic seas under the 2007 environmental conditions. The surface seawater appears in equilibrium or slightly supersaturated by CO 2 relative to atmosphere because of the increasing influence of river runoff and its input of terrestrial organic matter that mineralizes, in combination with the high surface water temperature during sea-ice-free conditions. This investigation shows the importance of processes that vary on small scales, both in time and space, for estimating the air-sea exchange of CO 2 . It stresses the need for highresolution coverage of ocean observations as well as time series. Furthermore, time series must include multi-year studies in the dynamic regions of the Arctic Ocean during these times of environmental change.

show abstract

“…While the minimum Ω A in that region reaches 0.9 in ORCA2, it drops to 0.4 in ORCA05 and 0.1 in ORCA025. That lower value in ORCA025 is more like that observed, e.g., down to 0.01 in the Laptev Sea (Semiletov et al, 2016). As these low extremes in Ω A are extremely local, they cannot be expected to be captured in coarse-resolution models (ORCA2).…”

Section: Effect On Aragonite Saturation Statementioning

confidence: 90%

Model constraints on the anthropogenic carbon budget of the Arctic Ocean

Terhaar¹,

Orr²,

Gehlen³

et al. 2018

Preprint

View full text Add to dashboard Cite

Abstract. The Arctic Ocean is projected to experience not only amplified climate change but also amplified ocean acidification.Modeling future acidification depends on our ability to simulate baseline conditions and changes over the industrial era. range from a previous data-based C ant storage estimate (2.5 to 3.3 Pg C). Yet those limits may each need to be reduced by 10 about 10% because data-based C ant concentrations in deep waters remain at ∼6 µmol kg −1 , while they should be almost negligible by analogy to the near-zero observed CFC-12 concentrations from which they are calculated. Across the three resolutions, there was roughly three times as much anthropogenic carbon that entered the Arctic Ocean through lateral transport than via the flux of CO 2 across the air-sea interface. Wider comparison to nine earth system models that participated in the Coupled Model Intercomparison Project Phase 5 (CMIP5) reveals much larger diversity of stored anthropogenic carbon and 15 lateral transport. Only the CMIP5 models with higher lateral transport obtain C ant inventories that are close to the data-based estimates. Increasing resolution also enhances acidification, e.g., with greater shoaling of the Arctic's average depth of the aragonite saturation horizon during 1960-2012, from 50 m in ORCA2 to 210 m in ORCA025. To assess the potential to further refine modeled estimates of the Arctic Ocean's C ant storage and acidification, sensitivity tests that adjust model parameters are needed given that century-scale global ocean biogeochemical simulations still cannot be run routinely at high resolution.

show abstract

Acidification of East Siberian Arctic Shelf waters through addition of freshwater and terrestrial carbon

Cited by 173 publications

References 44 publications

Collapsing Arctic coastlines

Collapsing Arctic coastlines

The spatial and interannual dynamics of the surface water carbonate system and air–sea CO<sub>2</sub> fluxes in the outer shelf and slope of the Eurasian Arctic Ocean

Model constraints on the anthropogenic carbon budget of the Arctic Ocean

Contact Info

Product

Resources

About

Acidification of East Siberian Arctic Shelf waters through addition of freshwater and terrestrial carbon

Cited by 173 publications

References 44 publications

Collapsing Arctic coastlines

Collapsing Arctic coastlines

The spatial and interannual dynamics of the surface water carbonate system and air–sea CO&lt;sub&gt;2&lt;/sub&gt; fluxes in the outer shelf and slope of the Eurasian Arctic Ocean

Model constraints on the anthropogenic carbon budget of the Arctic Ocean

Contact Info

Product

Resources

About

The spatial and interannual dynamics of the surface water carbonate system and air–sea CO<sub>2</sub> fluxes in the outer shelf and slope of the Eurasian Arctic Ocean