scholarly journals Antifreeze protein dispersion in eelpouts and related fishes reveals migration and climate alteration within the last 20 Ma

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0243273
Author(s):  
Rod S. Hobbs ◽  
Jennifer R. Hall ◽  
Laurie A. Graham ◽  
Peter L. Davies ◽  
Garth L. Fletcher

Antifreeze proteins inhibit ice growth and are crucial for the survival of supercooled fish living in icy seawater. Of the four antifreeze protein types found in fishes, the globular type III from eelpouts is the one restricted to a single infraorder (Zoarcales), which is the only clade know to have antifreeze protein-producing species at both poles. Our analysis of over 60 unique antifreeze protein gene sequences from several Zoarcales species indicates this gene family arose around 18 Ma ago, in the Northern Hemisphere, supporting recent data suggesting that the Arctic Seas were ice-laden earlier than originally thought. The Antarctic was subject to widespread glaciation over 30 Ma and the Notothenioid fishes that produce an unrelated antifreeze glycoprotein extensively exploited the adjoining seas. We show that species from one Zoarcales family only encroached on this niche in the last few Ma, entering an environment already dominated by ice-resistant fishes, long after the onset of glaciation. As eelpouts are one of the dominant benthic fish groups of the deep ocean, they likely migrated from the north to Antarctica via the cold depths, losing all but the fully active isoform gene along the way. In contrast, northern species have retained both the fully active (QAE) and partially active (SP) isoforms for at least 15 Ma, which suggests that the combination of isoforms is functionally advantageous.

Author(s):  
Ю.Л. Бордученко ◽  
И.Г. Малыгин ◽  
В.Ю. Каминский ◽  
В.А. Аксенов

Арктическая зона в XXI веке становится важнейшим гарантом устойчивого развития Российской Федерации. Вклад Севера в экономику России во многом будет определяться масштабами и темпами развития Арктической транспортной системы. Необходимо расширение коммерческого и научно-исследовательского судоходства, развитие транспортных узлов и коридоров, полярной авиации, грузопассажирских морских полярных перевозок. В этих условиях Россия в целях обеспечения своих геополитических интересов должна постоянно поддерживать активное присутствие в этом регионе. Оно выражается в проведении научных исследований, разведке и добыче полезных ископаемых, обеспечении морских грузоперевозок с использованием ледоколов и специализированных ледокольно-транспортных судов. Этого невозможно достичь без развития уникального атомного ледокольного флота. В настоящее время Россия является мировым лидером в области применения атомного ледокольного флота для решения транспортных задач в морях Арктики и неарктических замерзающих морях. Для успешной конкуренции России необходимо не упускать этого лидерства и постоянно развивать и совершенствовать атомный ледокольный флот как ключевое звено инфраструктуры функционирования Северного морского пути. В статье представлен краткий обзор текущего состояния и перспектив развития атомного ледокольного флота России. Показана определяющая роль атомного ледокольного флота в обеспечении судоходства по трассам Северного морского пути для развития экономики Арктического региона России. The Arctic zone in the XXI century is becoming the most important guarantor of the sustainable development of the Russian Federation. The contribution of the North to the Russian economy will largely be determined by the scale and pace of development of the Arctic Transport System. It is necessary to expand commercial and research shipping, develop transport hubs and corridors, polar aviation, and cargo and passenger sea polar transportation. In these circumstances, Russia must constantly maintain an active presence in this region in order to ensure its geopolitical interests. It is expressed in conducting scientific research, exploration and extraction of minerals, providing sea cargo transportation using icebreakers and specialized icebreaker-transport vessels. This cannot be achieved without the development of a unique nuclear icebreaker fleet. Currently, Russia is a world leader in the use of nuclear-powered icebreaking fleet for solving transport problems in the Arctic seas and non-Arctic freezing seas. For successful competition, Russia must not lose this leadership, constantly develop and improve the nuclear icebreaker fleet as a key link in the infrastructure of the Northern Sea Route. The article provides a brief overview of the current state and prospects for the development of the Russian nuclear icebreaker fleet. The article shows the decisive role of the nuclear icebreaker fleet in ensuring navigation along the Northern Sea Route for the development of the economy of the Arctic region of Russia.


Ocean Science ◽  
2017 ◽  
Vol 13 (3) ◽  
pp. 379-410 ◽  
Author(s):  
Burkard Baschek ◽  
Friedhelm Schroeder ◽  
Holger Brix ◽  
Rolf Riethmüller ◽  
Thomas H. Badewien ◽  
...  

Abstract. The Coastal Observing System for Northern and Arctic Seas (COSYNA) was established in order to better understand the complex interdisciplinary processes of northern seas and the Arctic coasts in a changing environment. Particular focus is given to the German Bight in the North Sea as a prime example of a heavily used coastal area, and Svalbard as an example of an Arctic coast that is under strong pressure due to global change.The COSYNA automated observing and modelling system is designed to monitor real-time conditions and provide short-term forecasts, data, and data products to help assess the impact of anthropogenically induced change. Observations are carried out by combining satellite and radar remote sensing with various in situ platforms. Novel sensors, instruments, and algorithms are developed to further improve the understanding of the interdisciplinary interactions between physics, biogeochemistry, and the ecology of coastal seas. New modelling and data assimilation techniques are used to integrate observations and models in a quasi-operational system providing descriptions and forecasts of key hydrographic variables. Data and data products are publicly available free of charge and in real time. They are used by multiple interest groups in science, agencies, politics, industry, and the public.


Author(s):  
TB Hoareau

AbstractAfter millennia of hunting and a population collapse, it is still challenging to understand the genetic consequences of whaling on the circumarctic bowhead whale. Here I use published modern mtDNA sequences from the Bering-Chukchi-Beaufort population and a new time calibration to show that late–glacial climate changes and whaling have been the major drivers of population change. Cultures that hunted in the Arctic Seas from as early as 5000 years ago appear to be responsible for successive declines of the population growth, bringing the effective size down to 38% of its pristine population size. The Thules and the Basques (year 1000–1730) who only hunted in the North Atlantic had a major impact on this North Pacific population, indicating that bowhead whale stocks respond to harvesting as a single population unit. Recent positive growth is inferred only after the end of commercial whaling in 1915, and for levels of harvesting that are close to the current annual quota of 67 whales. By unfolding the population history of the bowhead whale, I provide compelling evidence that mtDNA yields critical yet undervalued information for management and conservation of natural populations.


2020 ◽  
Author(s):  
Randelle M. Bundy ◽  
Alessandro Tagliabue ◽  
Nicholas J. Hawco ◽  
Peter L. Morton ◽  
Benjamin S. Twining ◽  
...  

Abstract. Cobalt (Co) is an important bioactive trace metal that can limit or co-limit phytoplankton growth in many regions of the ocean. Total dissolved and labile Co measurements in the Canadian sector of the Arctic Ocean during U.S. GEOTRACES Arctic expedition (GN01) and the Canadian International Polar Year-GEOTRACES expedition (GIPY14) revealed a dynamic biogeochemical cycle for Co in this basin. The major sources of Co in the Arctic were from shelf regions and rivers, with only minimal contributions from other freshwater sources (sea ice, snow) and aeolian deposition. The most striking feature was the extremely high concentrations of dissolved Co in the upper 100 m, with concentrations routinely exceeding 800 pmol L−1 over the shelf regions. This plume of high Co persisted throughout the Arctic basin and extended to the North Pole, where sources of Co shifted from primarily shelf-derived to riverine, as freshwater from Arctic rivers was entrained in the Transpolar Drift. Dissolved Co was also strongly organically-complexed in the Arctic, ranging from 70–100 % complexed in the surface and deep ocean, respectively. Deep water concentrations of dissolved Co were remarkably consistent throughout the basin (~ 55 pmol L−1), with concentrations reflecting those of deep Atlantic water and deep ocean scavenging of dissolved Co. A biogeochemical model of Co cycling was used to support the hypothesis that the majority of the high surface Co in the Arctic was emanating from the shelf. The model showed that the high concentrations of Co observed along the transect were due to the large shelf area of the Arctic, as well as dampened scavenging of Co by manganese (Mn)-oxidizing bacteria due to the lower temperatures. The majority of this scavenging appears to have occurred in the upper 200 m, with minimal additional scavenging below this depth. Preliminary evidence suggests that both dissolved and labile Co are increasing over time on the Arctic shelf, and the elevated surface concentrations of Co likely leads to a net flux of Co out of the Arctic, with implications for downstream biological uptake of Co in the North Atlantic and elevated Co in North Atlantic Deep Water. Understanding the current distributions of Co in the Arctic will be important for constraining changes to Co inputs resulting from regional intensification of freshwater fluxes from ice and permafrost melt in response to ongoing climate change.


2021 ◽  
Vol 18 (5) ◽  
pp. 1689-1701
Author(s):  
Jon Olafsson ◽  
Solveig R. Olafsdottir ◽  
Taro Takahashi ◽  
Magnus Danielsen ◽  
Thorarinn S. Arnarson

Abstract. The North Atlantic north of 50∘ N is one of the most intense ocean sink areas for atmospheric CO2 considering the flux per unit area, 0.27 Pg-C yr−1, equivalent to −2.5 mol C m−2 yr−1. The northwest Atlantic Ocean is a region with high anthropogenic carbon inventories. This is on account of processes which sustain CO2 air–sea fluxes, in particular strong seasonal winds, ocean heat loss, deep convective mixing, and CO2 drawdown by primary production. The region is in the northern limb of the global thermohaline circulation, a path for the long-term deep-sea sequestration of carbon dioxide. The surface water masses in the North Atlantic are of contrasting origins and character, with the northward-flowing North Atlantic Drift, a Gulf Stream offspring, on the one hand and on the other hand the cold southward-moving low-salinity Polar and Arctic waters with signatures from Arctic freshwater sources. We have studied by observation the CO2 air–sea flux of the relevant water masses in the vicinity of Iceland in all seasons and in different years. Here we show that the highest ocean CO2 influx is to the Arctic and Polar waters, respectively, -3.8±0.4 and -4.4±0.3 mol C m−2 yr−1. These waters are CO2 undersaturated in all seasons. The Atlantic Water is a weak or neutral sink, near CO2 saturation, after poleward drift from subtropical latitudes. These characteristics of the three water masses are confirmed by data from observations covering 30 years. We relate the Polar Water and Arctic Water persistent undersaturation and CO2 influx to the excess alkalinity derived from Arctic sources. Carbonate chemistry equilibrium calculations clearly indicate that the excess alkalinity may support at least 0.058 Pg-C yr−1, a significant portion of the North Atlantic CO2 sink. The Arctic contribution to the North Atlantic CO2 sink which we reveal was previously unrecognized. However, we point out that there are gaps and conflicts in the knowledge about the Arctic alkalinity and carbonate budgets and that future trends in the North Atlantic CO2 sink are connected to developments in the rapidly warming and changing Arctic. The results we present need to be taken into consideration for the following question: will the North Atlantic continue to absorb CO2 in the future as it has in the past?


Author(s):  
Alena Raspopina

The article considers the influence of economic and political factors on development of the state policy on the Northern Sea Route and its effective use. The success that Russia reached in the foreign policy, has determined the cautiousness or openness of its actions in the Arctic Seas. The article briefly describes the navigational and hydrographical traffic conditions in the Arctic Seas, the dangerous areas for sailing are noted in the text, as well as the new attempts that Russia made to establish navigation in the area. The intense activity in the North Polar Region, including research activity, was determined by economic interests, such as opportunities for maritime trade and transport routes development, as well as political interests, which include defense of own territories and development of new lands. The research is based on valuable sources of information on the North Polar Region, one of which is European and Russian geographical maps of the18th and 19th centuries, which managed to cover many blank spots, that resulted in delineating a clearer Arctic shoreline of Russia. Although the Northern Sea Route could hardly become a major transport channel due to the severe natural conditions, Russia tried to sustain its influence and defend its territories, especially when real threats to its national interests in the Arctic region arose.


2021 ◽  
Author(s):  
Leonid Yurganov ◽  
Dustin Carroll ◽  
Andrey Pnyushkov ◽  
Igor Polyakov ◽  
Hong Zhang

<p><span>Existence of strong seabed sources of methane, including gas hydrates, in the Arctic and sub-Arctic seas with proven oil/gas deposits </span><span>i</span><span>s well documented. Enhanced concentrations of dissolved methane in </span><span>deep layers</span><span> are widely observed</span><span>. </span><span>Many of </span><span>marine</span><span> sources are highly sensitive to climate change; however, the Arctic methane sea-to-air flux remains poorly understood</span><span>:</span><span> </span><span>harsh</span><span> natural conditions prevent in-situ measurements during winter. Satellite remote sensing, based on terrestrial outgoing Thermal IR radiation</span><span> </span><span>measurements</span><span>, provides a novel alternative to those efforts. We present year-round methane data from 3 orbital sounders since 2002. Those data confirm that negligible amounts of methane are fluxed from the seabed to the atmosphere during summer. In summer, the water column is strongly stratified from sea-ice melt </span><span>and solar warming. As a result, </span><span> ~90% of </span><span>dissolved </span><span>methane is oxidized by bacteria. Conversely, </span><span>some </span><span>marine areas are characterized by positive atmospheric methane anomalies that begin in November. During winter, ocean stratification weakens</span><span>,</span><span> </span><span>convection and </span><span>winter storms </span><span>mix the water column efficiently</span><span>. We also find that the amplitudes of the seasonal cycles over Kara and Okhotsk Seas have increased during last 18 years</span><span> </span><span>due to winter concentration growth. There may be several factors </span><span>responsible for sea-air flux</span><span>: </span><span>growing emission from clathrates due to warming</span><span>, changes in methane transport from the seabed to the surface, changes in microbial </span><span>oxidation</span><span>, </span><span>ice cover, </span><span>etc</span><span>. Finally, </span><span>methane</span><span> remote sensing results are compared to available observations of temperature in deep ocean layers, estimates of Mixed Layer Depth, and satellite microwave sea-ice cover measurements.</span></p><p> </p>


2020 ◽  
Vol 217 ◽  
pp. 04002
Author(s):  
Ksenia Derevtsova ◽  
Vladislav Ginevskii ◽  
Gleb Kataev ◽  
Semion Kim ◽  
Polina Veselova

The article tells about the risks of low-culture construction of oil facilities on the Arctic shelf. The long-term, practically neglected exploitation of the unique natural resources of the Russian North and the low culture of their development led in a number of its regions, including the waters of the Arctic seas with islands, to an emergency ecological situation - the partial and sometimes complete destruction of the fragile Arctic natural habitat of the small peoples of the North and the created cities and villages. Without proper environmental support, economic activities continue in the field of extraction, transportation and processing of natural resources. The progressive pollution of rivers and lakes leads to a qualitative depletion of water resources - a change in the composition of the waters of the Arctic Ocean. The danger of oil pollution of the marine environment is associated with plans for its production on the continental shelf of the Russian Federation. The oil and gas production complex in the Russian Arctic regions are being formed on the basis of already discovered fields and will develop as other promising fields are developed.


Author(s):  
Valentin Sapunov

This chapter aims at the consideration of world temperature dynamics and its prediction in the polar regions of the planet. The global warming started in the 17th century and has been progressing since then. The decline in average global temperature began in 1997. There exist various factors which affect the process, the abiotic ones being among the major in controlling the climate. The climate is also dependent on the interaction between abiotic, biotic, and social spheres. This system seems rather stable and not very much dependent on human activity. The effects of contemporary cooling are not expected to be significant for the mankind but are definitely important for the polar regions. In the Arctic, the temperature is increasing. The one in the Antarctic declines. The average global temperature thus becomes variable. Modern science is able to predict climate change, but extensive studies free of political and economic pressure have to be conducted.


2016 ◽  
Author(s):  
B. Baschek ◽  
F. Schroeder ◽  
H. Brix ◽  
R. Riethmüller ◽  
T. H. Badewien ◽  
...  

Abstract. The Coastal Observing System for Northern and Arctic Seas (COSYNA) was established in order to better understand the complex interdisciplinary processes of northern seas and the arctic coasts in a changing environment. Particular focus is given to the German Bight in the North Sea as a prime example for a heavily used coastal area, and Svalbard as an example of an arctic coast that is under strong pressure due to global change. The automated observing and modelling system COSYNA is designed to monitor real time conditions, provide short-term forecasts and data products, and to assess the impact of anthropogenically induced change. Observations are carried out combining satellite and radar remote sensing with various in situ platforms. Novel sensors, instruments, and algorithms are developed to further improve the understanding of the interdisciplinary interactions between physics, biogeochemistry, and the ecology of coastal seas. New modelling and data assimilation techniques are used to integrate observations and models in a quasi-operational system providing descriptions and forecasts of key hydrographic variables. Data and data products are publically available free of charge and in real time. They are used by multiple interest groups in science, agencies, politics, industry, and the public.


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