Cost-Effective Technologies to Study the Arctic Ocean Environment †

The Arctic region is known to be severely affected by climate change, with evident alterations in both physical and biological processes. Monitoring the Arctic Ocean ecosystem is key to understanding the impact of natural and human-induced change on the environment. Large data sets are required to monitor the Arctic marine ecosystem and validate high-resolution satellite observations (e.g., Sentinel), which are necessary to feed climatic and biogeochemical forecasting models. However, the Global Observing System needs to complete its geographic coverage, particularly for the harsh, extreme environment of the Arctic Region. In this scenario, autonomous systems are proving to be valuable tools for increasing the resolution of existing data. To this end, a low-cost, miniaturized and flexible probe, ArLoC (Arctic Low-Cost probe), was designed, built and installed on an innovative unmanned marine vehicle, the PROTEUS (Portable RObotic TEchnology for Unmanned Surveys), during a preliminary scientific campaign in the Svalbard Archipelago within the UVASS project. This study outlines the instrumentation used and its design features, its preliminary integration on PROTEUS and its test results.

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Nitrate Consumers in Arctic Marine Eukaryotic Communities: Comparative Diversities of 18S rRNA, 18S rRNA Genes, and Nitrate Reductase Genes

Applied and Environmental Microbiology ◽

10.1128/aem.00247-19 ◽

2019 ◽

Vol 85 (14) ◽

Author(s):

André M. Comeau ◽

Marcos G. Lagunas ◽

Karen Scarcella ◽

Diana E. Varela ◽

Connie Lovejoy

Keyword(s):

Nitrate Reductase ◽

Arctic Ocean ◽

18S Rrna ◽

Arctic Region ◽

The Arctic ◽

Available Nitrogen ◽

Clone Libraries ◽

Microbial Eukaryotes ◽

The Arctic Ocean ◽

The Arctic Region

ABSTRACT For photosynthetic microbial eukaryotes, the rate-limiting step in NO3− assimilation is its reduction to nitrite (NO2−), which is catalyzed by assimilatory nitrate reductase (NR). Oceanic productivity is primarily limited by available nitrogen and, although nitrate is the most abundant form of available nitrogen in oceanic waters, little is known about the identity of microbial eukaryotes that take up nitrate. This lack of knowledge is especially severe for ice-covered seas that are being profoundly affected by climate change. To address this, we examined the distribution and diversity of NR genes in the Arctic region by way of clone libraries and data mining of available metagenomes (total of 4.24 billion reads). We directly compared NR clone phylogenies with the V4 region of the 18S rRNA gene (DNA pool) and 18S rRNA (RNA pool) at two ice-influenced stations in the Canada Basin (Beaufort Sea). The communities from the two nucleic acid templates were similar at the level of major groups, and species identified by way of NR gene phylogeny and microscopy were a subset of the 18S results. Most NR genes from arctic clone libraries matched diatoms and chromist nanoflagellates, including novel clades, while the NR genes in arctic eukaryote metagenomes were dominated by chlorophyte NR, in keeping with the ubiquitous occurrence of Mamiellophyceae in the Arctic Ocean. Overall, these data suggest that a dynamic and mixed eukaryotic community utilizes nitrate across the Arctic region, and they show the potential utility of NR as a tool to identify ongoing changes in arctic photosynthetic communities. IMPORTANCE To better understand the diversity of primary producers in the Arctic Ocean, we targeted a nitrogen cycle gene, NR, which is required for phytoplankton to assimilate nitrate into organic forms of nitrogen macromolecules. We compared this to the more detailed taxonomy from ice-influenced stations using a general taxonomic gene (18S rRNA). NR genes were ubiquitous and could be classified as belonging to diatoms, dinoflagellates, other flagellates, chlorophytes, and unknown microbial eukaryotes, suggesting novel diversity of both species and metabolism in arctic phytoplankton.

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Geodynamic evolution of the Arctic Ocean and modern problems in geological studies of the Arctic region

Herald of the Russian Academy of Sciences ◽

10.1134/s1019331615030193 ◽

2015 ◽

Vol 85 (3) ◽

pp. 206-212

Author(s):

V. A. Vernikovsky ◽

N. L. Dobretsov

Keyword(s):

Arctic Ocean ◽

Arctic Region ◽

The Arctic ◽

Geodynamic Evolution ◽

The Arctic Ocean ◽

The Arctic Region

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Airline Navigation in Polar Areas

Journal of Navigation ◽

10.1017/s0373463300017707 ◽

1958 ◽

Vol 11 (4) ◽

pp. 356-360 ◽

Cited By ~ 7

Author(s):

E. S. Pedersen

Keyword(s):

Los Angeles ◽

Arctic Ocean ◽

Arctic Region ◽

The Arctic ◽

Commercial Aircraft ◽

The Arctic Ocean ◽

The Arctic Region

In 1952 the first transpolar flight by a commercial aircraft was carried out. During the six years that have since passed, S.A.S. aircraft have made 1635 flights across the arctic region representing approximately 26,000 flying hours. Our experience in polar navigation has been built up first on a large number of charter flights, then on regular flights on the sub-polar route to Los Angeles, and finally on regular flights across the Arctic Ocean to Japan.

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Legal Complexities of Hybrid Threats in the Arctic Region

Teisė ◽

10.15388/teise.2019.112.6 ◽

2019 ◽

Vol 112 ◽

pp. 107-123

Author(s):

Alaa Al-Aridi

Keyword(s):

Arctic Ocean ◽

Use Of Force ◽

Arctic Region ◽

Legal Framework ◽

The Arctic ◽

Maritime Law ◽

The Arctic Ocean ◽

Hybrid Threats ◽

The Arctic Region

This article will focus on the legal framework that applies to the Arctic ocean and highlight the legal grey areas that hybrid campaigns could invest in to violate international maritime law and law relating to the use of force.

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Pan-Arctic aerosol number size distributions: seasonality and transport patterns

Atmospheric Chemistry and Physics ◽

10.5194/acp-17-8101-2017 ◽

2017 ◽

Vol 17 (13) ◽

pp. 8101-8128 ◽

Cited By ~ 33

Author(s):

Eyal Freud ◽

Radovan Krejci ◽

Peter Tunved ◽

Richard Leaitch ◽

Quynh T. Nguyen ◽

...

Keyword(s):

Arctic Ocean ◽

Regional Scale ◽

Arctic Region ◽

The Arctic ◽

Research Station ◽

Size Distributions ◽

Back Trajectories ◽

Accumulation Mode ◽

Source Regions ◽

The Arctic Ocean

Abstract. The Arctic environment has an amplified response to global climatic change. It is sensitive to human activities that mostly take place elsewhere. For this study, a multi-year set of observed aerosol number size distributions in the diameter range of 10 to 500 nm from five sites around the Arctic Ocean (Alert, Villum Research Station – Station Nord, Zeppelin, Tiksi and Barrow) was assembled and analysed.A cluster analysis of the aerosol number size distributions revealed four distinct distributions. Together with Lagrangian air parcel back-trajectories, they were used to link the observed aerosol number size distributions with a variety of transport regimes. This analysis yields insight into aerosol dynamics, transport and removal processes, on both an intra- and an inter-monthly scale. For instance, the relative occurrence of aerosol number size distributions that indicate new particle formation (NPF) event is near zero during the dark months, increases gradually to ∼ 40 % from spring to summer, and then collapses in autumn. Also, the likelihood of Arctic haze aerosols is minimal in summer and peaks in April at all sites.The residence time of accumulation-mode particles in the Arctic troposphere is typically long enough to allow tracking them back to their source regions. Air flow that passes at low altitude over central Siberia and western Russia is associated with relatively high concentrations of accumulation-mode particles (Nacc) at all five sites – often above 150 cm−3. There are also indications of air descending into the Arctic boundary layer after transport from lower latitudes.The analysis of the back-trajectories together with the meteorological fields along them indicates that the main driver of the Arctic annual cycle of Nacc, on the larger scale, is when atmospheric transport covers the source regions for these particles in the 10-day period preceding the observations in the Arctic. The scavenging of these particles by precipitation is shown to be important on a regional scale and it is most active in summer. Cloud processing is an additional factor that enhances the Nacc annual cycle.There are some consistent differences between the sites that are beyond the year-to-year variability. They are the result of differences in the proximity to the aerosol source regions and to the Arctic Ocean sea-ice edge, as well as in the exposure to free-tropospheric air and in precipitation patterns – to mention a few. Hence, for most purposes, aerosol observations from a single Arctic site cannot represent the entire Arctic region. Therefore, the results presented here are a powerful observational benchmark for evaluation of detailed climate and air chemistry modelling studies of aerosols throughout the vast Arctic region.

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Importance of Human-Induced Nitrogen Flux Increases for Simulated Arctic Warming

Journal of Climate ◽

10.1175/jcli-d-20-0180.1 ◽

2021 ◽

Vol 34 (10) ◽

pp. 3799-3819

Author(s):

Hyung-Gyu Lim ◽

Jong-Yeon Park ◽

John P. Dunne ◽

Charles A. Stock ◽

Sung-Ho Kang ◽

...

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

The Arctic ◽

Biogeochemical Model ◽

Biological Feedback ◽

Arctic Warming ◽

The Arctic Ocean ◽

N Fluxes ◽

The Impact ◽

Chlorophyll Concentrations

AbstractHuman activities such as fossil fuel combustion, land-use change, nitrogen (N) fertilizer use, emission of livestock, and waste excretion accelerate the transformation of reactive N and its impact on the marine environment. This study elucidates that anthropogenic N fluxes (ANFs) from atmospheric and river deposition exacerbate Arctic warming and sea ice loss via physical–biological feedback. The impact of physical–biological feedback is quantified through a suite of experiments using a coupled climate–ocean–biogeochemical model (GFDL-CM2.1-TOPAZ) by prescribing the preindustrial and contemporary amounts of riverine and atmospheric N fluxes into the Arctic Ocean. The experiment forced by ANFs represents the increase in ocean N inventory and chlorophyll concentrations in present and projected future Arctic Ocean relative to the experiment forced by preindustrial N flux inputs. The enhanced chlorophyll concentrations by ANFs reinforce shortwave attenuation in the upper ocean, generating additional warming in the Arctic Ocean. The strongest responses are simulated in the Eurasian shelf seas (Kara, Barents, and Laptev Seas; 65°–90°N, 20°–160°E) due to increased N fluxes, where the annual mean surface temperature increase by 12% and the annual mean sea ice concentration decrease by 17% relative to the future projection, forced by preindustrial N inputs.

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Regional variability of acidification in the Arctic: a sea of contrasts

Biogeosciences ◽

10.5194/bg-11-293-2014 ◽

2014 ◽

Vol 11 (2) ◽

pp. 293-308 ◽

Cited By ~ 23

Author(s):

E. E. Popova ◽

A. Yool ◽

Y. Aksenov ◽

A. C. Coward ◽

T. R. Anderson

Keyword(s):

Climate Change ◽

Primary Production ◽

Arctic Ocean ◽

Canadian Arctic ◽

Atmospheric Co2 ◽

The Arctic ◽

Canadian Arctic Archipelago ◽

Regional Variability ◽

The Arctic Ocean ◽

The Impact

Abstract. The Arctic Ocean is a region that is particularly vulnerable to the impact of ocean acidification driven by rising atmospheric CO2, with potentially negative consequences for calcifying organisms such as coccolithophorids and foraminiferans. In this study, we use an ocean-only general circulation model, with embedded biogeochemistry and a comprehensive description of the ocean carbon cycle, to study the response of pH and saturation states of calcite and aragonite to rising atmospheric pCO2 and changing climate in the Arctic Ocean. Particular attention is paid to the strong regional variability within the Arctic, and, for comparison, simulation results are contrasted with those for the global ocean. Simulations were run to year 2099 using the RCP8.5 (an Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) scenario with the highest concentrations of atmospheric CO2). The separate impacts of the direct increase in atmospheric CO2 and indirect effects via impact of climate change (changing temperature, stratification, primary production and freshwater fluxes) were examined by undertaking two simulations, one with the full system and the other in which atmospheric CO2 was prevented from increasing beyond its preindustrial level (year 1860). Results indicate that the impact of climate change, and spatial heterogeneity thereof, plays a strong role in the declines in pH and carbonate saturation (Ω) seen in the Arctic. The central Arctic, Canadian Arctic Archipelago and Baffin Bay show greatest rates of acidification and Ω decline as a result of melting sea ice. In contrast, areas affected by Atlantic inflow including the Greenland Sea and outer shelves of the Barents, Kara and Laptev seas, had minimal decreases in pH and Ω because diminishing ice cover led to greater vertical mixing and primary production. As a consequence, the projected onset of undersaturation in respect to aragonite is highly variable regionally within the Arctic, occurring during the decade of 2000–2010 in the Siberian shelves and Canadian Arctic Archipelago, but as late as the 2080s in the Barents and Norwegian seas. We conclude that, for future projections of acidification and carbonate saturation state in the Arctic, regional variability is significant and needs to be adequately resolved, with particular emphasis on reliable projections of the rates of retreat of the sea ice, which are a major source of uncertainty.

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Recent Sea Ice Decline Did Not Significantly Increase the Total Liquid Freshwater Content of the Arctic Ocean

Journal of Climate ◽

10.1175/jcli-d-18-0237.1 ◽

2018 ◽

Vol 32 (1) ◽

pp. 15-32 ◽

Cited By ~ 11

Author(s):

Qiang Wang ◽

Claudia Wekerle ◽

Sergey Danilov ◽

Dmitry Sidorenko ◽

Nikolay Koldunov ◽

...

Keyword(s):

Spatial Distribution ◽

Sea Ice ◽

Arctic Ocean ◽

Ocean Circulation ◽

General Circulation ◽

The Arctic ◽

Sea Ice Decline ◽

The Arctic Ocean ◽

Eurasian Basin ◽

The Impact

Abstract The freshwater stored in the Arctic Ocean is an important component of the global climate system. Currently the Arctic liquid freshwater content (FWC) has reached a record high since the beginning of the last century. In this study we use numerical simulations to investigate the impact of sea ice decline on the Arctic liquid FWC and its spatial distribution. The global unstructured-mesh ocean general circulation model Finite Element Sea Ice–Ocean Model (FESOM) with 4.5-km horizontal resolution in the Arctic region is applied. The simulations show that sea ice decline increases the FWC by freshening the ocean through sea ice meltwater and modifies upper ocean circulation at the same time. The two effects together significantly increase the freshwater stored in the Amerasian basin and reduce its amount in the Eurasian basin. The salinification of the upper Eurasian basin is mainly caused by the reduction in the proportion of Pacific Water and the increase in that of Atlantic Water (AW). Consequently, the sea ice decline did not significantly contribute to the observed rapid increase in the Arctic total liquid FWC. However, the changes in the Arctic freshwater spatial distribution indicate that the influence of sea ice decline on the ocean environment is remarkable. Sea ice decline increases the amount of Barents Sea branch AW in the upper Arctic Ocean, thus reducing its supply to the deeper Arctic layers. This study suggests that all the dynamical processes sensitive to sea ice decline should be taken into account when understanding and predicting Arctic changes.

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Cryospheric Impacts of Soviet River Diversion Schemes

Annals of Glaciology ◽

10.3189/1984aog5-1-61-68 ◽

1984 ◽

Vol 5 ◽

pp. 61-68 ◽

Cited By ~ 4

Author(s):

T. Holt ◽

P. M. Kelly ◽

B. S. G. Cherry

Keyword(s):

Sea Ice ◽

Arctic Ocean ◽

River Discharge ◽

Large Scale ◽

Arctic Sea Ice ◽

The Arctic ◽

Sea Ice Concentration ◽

Ice Concentration ◽

The Arctic Ocean ◽

The Impact

Soviet plans to divert water from rivers flowing into the Arctic Ocean have led to research into the impact of a reduction in discharge on Arctic sea ice. We consider the mechanisms by which discharge reductions might affect sea-ice cover and then test various hypotheses related to these mechanisms. We find several large areas over which sea-ice concentration correlates significantly with variations in river discharge, supporting two particular hypotheses. The first hypothesis concerns the area where the initial impacts are likely to which is the Kara Sea. Reduced riverflow is associated occur, with decreased sea-ice concentration in October, at the time of ice formation. This is believed to be the result of decreased freshening of the surface layer. The second hypothesis concerns possible effects on the large-scale current system of the Arctic Ocean and, in particular, on the inflow of Atlantic and Pacific water. These effects occur as a result of changes in the strength of northward-flowing gradient currents associated with variations in river discharge. Although it is still not certain that substantial transfers of riverflow will take place, it is concluded that the possibility of significant cryospheric effects and, hence, large-scale climate impact should not be neglected.

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Mapping of the maritime jurisdiction for Arctic Navigation

Abstracts of the ICA ◽

10.5194/ica-abs-1-221-2019 ◽

2019 ◽

Vol 1 ◽

pp. 1-1

Author(s):

Haiyan Liu ◽

Xiaoping Pang

Keyword(s):

Arctic Ocean ◽

Route Planning ◽

Arctic Region ◽

The Arctic ◽

Law Of The Sea ◽

The Arctic Ocean ◽

United Nations Convention ◽

Arctic Navigation ◽

Navigation Planning ◽

International Conventions

Abstract. In recent years, Arctic glaciers have gradually melted due to the global warming, which makes the exploitation of Arctic and its seabed resources possible. Though numerous disagreements and potentials over Arctic maritime jurisdiction still exist, the surround-Arctic nations have agreed the United Nations' Convention on the Law of the Sea to divide the Arctic Ocean into zones that can be regulated and exploited. The IBRU of Durham University has mapped the known claims, agreed boundaries and potential claims of the surround-Arctic nations in the Arctic to clear the maritime jurisdiction in the region. However, different countries may have different requirements within their jurisdictional areas. Clarifying these requirements is essential for Arctic Navigation of investigation ships and merchant ships for their route planning.In this paper, based on the map of maritime jurisdiction and boundaries in Arctic region (IBRU), we analysed the international conventions and relevant laws of the surround-Arctic nations to find out the rights and obligations of ships in different zones. The limitations on activities and recommendations on navigation planning are marked for different zones according to different purposes, i.e. science or commerce. The map could not only provide navigational guidance for the activities in the Arctic Ocean, but offer references for the countries not surrounding the Arctic in the formulation of the Arctic strategies.

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