Gomphonema svalbardense sp. nov., a new freshwater diatom species (Bacillariophyta) from the Arctic Region

During a survey of freshwater diatoms from lakes in the region of Petuniabukta on Spitsbergen (Svalbard Archipelago) a new Gomphonema species, G. svalbardense sp. nov., has been recorded. The new taxon was previously cited in the literature as G. angustatum var. undulatum but this identification proved to be erroneous. Detailed morphology description of G. svalbardense based on light and scanning electron microscopy is presented in this paper and the morphological features of the taxon have been compared with similar species. Gomphonema svalbardense is characterized by its typical linear, almost naviculoid outline with undulating margins, with clearly inflated central part, asymmetric central area, lateral raphe with simple straight proximal endings and the weakly radiate striae. History, ecology and biogeography of the species, mainly based on literature data, have been included.

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SEISMICITY of the ARCTIC in 2015

Zemletriaseniia Severnoi Evrazii [Earthquakes in Northern Eurasia] ◽

10.35540/1818-6254.2021.24.20 ◽

2021 ◽

pp. 210-216

Author(s):

A. Morozov ◽

G. Avetisov ◽

G. Antonovskaya ◽

V. Asming ◽

S. Baranov ◽

...

Keyword(s):

Seismic Station ◽

Arctic Region ◽

The Arctic ◽

Earthquake Catalog ◽

Svalbard Archipelago ◽

Ocean Ridges ◽

The North ◽

Franz Josef Land ◽

Barents And Kara Seas ◽

The Arctic Region

The article provides an overview and analysis of seismicity within the boundaries of the Arctic region for 2015, a description of seismic station networks, and processing methods. The catalog of earthquakes in the Arctic region was compiled on the basis of catalogs of several organizations and seismological centers. In total, 334 earthquakes are included in the earthquake catalog. Most of the earthquakes that occurred in 2015, including all the strongest earthquakes, were located within the mid-ocean ridges of Mon, Knipovich and Gakkel. In the offshore territories, most of the earthquakes were confined to the Svalbard archipelago, in particular, to the seismically active zone in the Sturfjord strait. The renewal of instrumental seismological observations in 2011 (station ZFI) on Alexandra Land Island in the Franz Josef Land archipelago made it possible to record weak earthquakes in the north of the shelf of the Barents and Kara Seas. For twelve earthquakes, the focal mechanism parameters are presented according to the Global CMT catalog.

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Halamphora daochengensis sp. nov., a new freshwater diatom species (Bacillariophyceae) from a small mountain lake, Sichuan Province, China

Phytotaxa ◽

10.11646/phytotaxa.404.1.2 ◽

2019 ◽

Vol 404 (1) ◽

pp. 12 ◽

Cited By ~ 2

Author(s):

WEI ZHANG ◽

TING WANG ◽

ZLATKO LEVKOV ◽

INGRID JÜTTNER ◽

LUC ECTOR ◽

...

Keyword(s):

New Species ◽

Nature Reserve ◽

Sichuan Province ◽

Mountain Lake ◽

Morphological Description ◽

Similar Species ◽

Dorsal Margin ◽

Diatom Species ◽

Freshwater Diatoms ◽

Freshwater Diatom

During a survey of freshwater diatoms from a mountain lake, Lake Congqiancuo, Haizishan Nature Reserve, Yading, Daocheng County, Sichuan Province, China, a new Halamphora species, Halamphora daochengensis sp. nov. was found. A detailed morphological description of the new species is presented, based on light and scanning electron microscopy. The main features of H. daochengensis are dorsiventral, semi-lanceolate valves with a strongly triundulate dorsal margin and valve ends distinctly protracted and capitate. The new species is compared with other similar species including Halamphora dusenii and H. normanii var. undulata which differ in size, valve shape, stria density and ultrastructure.

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Cross-polar transport and scavenging of Siberian aerosols containing black carbon during the 2012 ACCESS summer campaign

Atmospheric Chemistry and Physics ◽

10.5194/acp-17-10969-2017 ◽

2017 ◽

Vol 17 (18) ◽

pp. 10969-10995 ◽

Cited By ~ 13

Author(s):

Jean-Christophe Raut ◽

Louis Marelle ◽

Jerome D. Fast ◽

Jennie L. Thomas ◽

Bernadett Weinzierl ◽

...

Keyword(s):

Black Carbon ◽

Biomass Burning ◽

Large Scale ◽

Arctic Region ◽

Anthropogenic Sources ◽

The Arctic ◽

Convective Precipitation ◽

Svalbard Archipelago ◽

Wet Removal ◽

The Arctic Region

Abstract. During the ACCESS airborne campaign in July 2012, extensive boreal forest fires resulted in significant aerosol transport to the Arctic. A 10-day episode combining intense biomass burning over Siberia and low-pressure systems over the Arctic Ocean resulted in efficient transport of plumes containing black carbon (BC) towards the Arctic, mostly in the upper troposphere (6–8 km). A combination of in situ observations (DLR Falcon aircraft), satellite analysis and WRF-Chem simulations is used to understand the vertical and horizontal transport mechanisms of BC with a focus on the role of wet removal. Between the northwestern Norwegian coast and the Svalbard archipelago, the Falcon aircraft sampled plumes with enhanced CO concentrations up to 200 ppbv and BC mixing ratios up to 25 ng kg−1. During transport to the Arctic region, a large fraction of BC particles are scavenged by two wet deposition processes, namely wet removal by large-scale precipitation and removal in wet convective updrafts, with both processes contributing almost equally to the total accumulated deposition of BC. Our results underline that applying a finer horizontal resolution (40 instead of 100 km) improves the model performance, as it significantly reduces the overestimation of BC levels observed at a coarser resolution in the mid-troposphere. According to the simulations at 40 km, the transport efficiency of BC (TEBC) in biomass burning plumes was larger (60 %), because it was impacted by small accumulated precipitation along trajectory (1 mm). In contrast TEBC was small (< 30 %) and accumulated precipitation amounts were larger (5–10 mm) in plumes influenced by urban anthropogenic sources and flaring activities in northern Russia, resulting in transport to lower altitudes. TEBC due to large-scale precipitation is responsible for a sharp meridional gradient in the distribution of BC concentrations. Wet removal in cumulus clouds is the cause of modeled vertical gradient of TEBC, especially in the mid-latitudes, reflecting the distribution of convective precipitation, but is dominated in the Arctic region by the large-scale wet removal associated with the formation of stratocumulus clouds in the planetary boundary layer (PBL) that produce frequent drizzle.

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Variability of the mixed phase in the Arctic with a focus on the Svalbard region: a study based on spaceborne active remote sensing

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-14-23453-2014 ◽

2014 ◽

Vol 14 (16) ◽

pp. 23453-23497

Author(s):

G. Mioche ◽

O. Jourdan ◽

M. Ceccaldi ◽

J. Delanoë

Keyword(s):

Climate Change ◽

Remote Sensing ◽

Arctic Region ◽

Supercooled Liquid ◽

Mixed Phase ◽

The Arctic ◽

Retrieval Algorithm ◽

Temporal And Spatial Distribution ◽

Svalbard Archipelago ◽

The Arctic Region

Abstract. The Arctic region is known to be very sensitive to climate change. Clouds and in particular mixed phase clouds (MPC) remain one of the greatest sources of uncertainties in the modeling of the Arctic response to climate change due to an inaccurate representation of their variability and their quantification. In this study, we present a characterization of the vertical, spatial and seasonal variability of Arctic clouds and MPC over the whole Arctic region based on satellite active remote sensing observations. MPC properties in the region of Svalbard archipelago (78° N, 15° E) are also investigated. The occurrence frequency of clouds and MPC are determined from CALIPSO/CLOUDSAT measurements processed with the DARDAR retrieval algorithm which allows for a reliable cloud thermodynamic phase classification (warm liquid, supercooled liquid, ice, mixing of ice and supercooled liquid). Significant differences are observed between MPC variability over the whole Arctic region and over the Svalbard region. Results show that MPC are ubiquitous all along the year, with a minimum occurrence of 30% in winter and 50% during the rest of the year, in average over the whole Arctic. Over the Svalbard region, MPC occurrence is more constant with time with larger values (55%) compared to the average observed in the Arctic. MPC are especially located at low altitudes, below 3000 m, where their frequency of occurrence reaches 90%, in particular during winter, spring and autumn. Moreover, results highlight that MPC statistically prevail over sea. The temporal and spatial distribution of MPC over the Svalbard region seems to be linked to the contribution of moister air and warmer water from the North Atlantic Ocean which contribute to the initiation of the liquid water phase. Over the whole Arctic, and particularly in western regions, the increase of MPC occurrence from spring to autumn could be connected to the sea ice melting. During this period, the open water transports a part of the warm water from the Svalbard region to the rest of the Arctic region. This facilitates the vertical transfer of moisture and thus the persistence of the liquid phase. A particular attention is also paid on the measurements uncertainties and how they could affect our results.

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Cost-Effective Technologies to Study the Arctic Ocean Environment †

Sensors ◽

10.3390/s18072257 ◽

2018 ◽

Vol 18 (7) ◽

pp. 2257 ◽

Cited By ~ 6

Author(s):

Viviana Piermattei ◽

Alice Madonia ◽

Simone Bonamano ◽

Riccardo Martellucci ◽

Gabriele Bruzzone ◽

...

Keyword(s):

Arctic Ocean ◽

Low Cost ◽

Marine Ecosystem ◽

Arctic Region ◽

Extreme Environment ◽

The Arctic ◽

Svalbard Archipelago ◽

The Arctic Ocean ◽

The Impact ◽

The Arctic Region

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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Seismicity of the Arctic in the Early Twentieth Century: Relocation of the 1904–1920 Earthquakes

Bulletin of the Seismological Society of America ◽

10.1785/0120190018 ◽

2019 ◽

Vol 109 (5) ◽

pp. 2000-2008 ◽

Cited By ~ 1

Author(s):

Alexey N. Morozov ◽

Natalya V. Vaganova ◽

Evgeniya V. Shakhova ◽

Yana V. Konechnaya ◽

Vladimir E. Asming ◽

...

Keyword(s):

Twentieth Century ◽

Seismic Waves ◽

Barents Sea ◽

Seismic Hazard Assessment ◽

Arctic Region ◽

Global Network ◽

The Arctic ◽

Svalbard Archipelago ◽

Early Twentieth Century ◽

The Arctic Region

Abstract The parameters of earthquake hypocenters in the Arctic at the beginning of the twentieth century, published by researchers in the first half of the twentieth century, are still used today for building maps of epicenters of instrumental earthquakes. However, they are based on bulletins that did not use data from all seismic stations operating during that period, and on approximate ideas about the propagation of seismic waves in the Earth. We relocated earthquakes recorded within the Arctic region beginning from the early twentieth century with a view to creating a relocated catalog. For the relocation, we collected all available seismic bulletins from the global network using data acquired for the International Seismological Centre–Global Earthquake Model (ISC‐GEM) catalog, the EuroSeismos project, the Geophysical Survey of the Russian Academy of Sciences, and the Russian State Library. The relocation was performed using a modified method of generalized beamforming and the ak135 velocity model. The relocation procedure was applied to 18 of 25 earthquakes in the Arctic region. The new coordinates of some earthquakes turned out to be significantly different from those that were determined previously. As a result, this may have a significant impact on the final seismic hazard assessment of the territory of the Severnaya Zemlya and Franz Josef Land archipelagoes, which are characterized by weak seismicity. Most of the relocated earthquake epicenters are confined to major seismic zones in the Arctic, namely, mid‐ocean ridges, the Svalbard Archipelago, and the Laptev Sea shelf. One earthquake, that of 14 October 1914 with magnitude Mw(ISC‐GEM)=6.6, occurred in the shelf of the Barents Sea in the “continent–ocean” transition zone near the Franz Victoria graben.

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Sellaphora davoutiana sp. nov.: a new freshwater diatom species (Sellaphoraceae, Bacillariophyta) in lakes of Northeastern France

Phytotaxa ◽

10.11646/phytotaxa.346.3.6 ◽

2018 ◽

Vol 346 (3) ◽

pp. 269 ◽

Cited By ~ 3

Author(s):

DAVID HEUDRE ◽

CARLOS E. WETZEL ◽

LAURA MOREAU ◽

LUC ECTOR

Keyword(s):

Central Area ◽

Mountain Lakes ◽

Similar Species ◽

Diatom Species ◽

Freshwater Lakes ◽

Floristic Survey ◽

Glacial Origin ◽

Northeastern France ◽

Scanning Electron ◽

Freshwater Diatom

During a floristic survey of freshwater lakes in the French Grand Est region, a new Sellaphora species (Bacillariophyceae) was found. Its morphology was examined in detail using light and scanning electron microscopy to formally describe it. Sellaphora davoutiana sp. nov. has elliptic-lanceolate valves with broadly protracted, subcapitate apices. Based on available literature, it is compared to morphologically similar species such as Navicula detenta, S. sardiniensis, S. sassiana and S. smirnovii. Valve dimensions, central area shape and striae density and pattern of this new species allow its separation from them. Sellaphora davoutiana has been found in three low-mountain lakes of glacial origin in Northeastern France, with watershed on granitic substratum. Additionally, illustrations of Hustedt type material of Navicula detenta are provided, and this taxon is formally transferred to the genus Adlafia.

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ARCTIC

Zemletriaseniia Severnoi Evrazii [Earthquakes in Northern Eurasia] ◽

10.35540/1818-6254.2020.23.22 ◽

2020 ◽

pp. 228-234

Author(s):

Alexey Morozov ◽

G. Avetisov ◽

V. Asming ◽

S. Baranov ◽

N. Vaganova ◽

...

Keyword(s):

Seismic Station ◽

Arctic Region ◽

The Arctic ◽

Earthquake Catalog ◽

Svalbard Archipelago ◽

Ocean Ridges ◽

The North ◽

Franz Josef Land ◽

Barents And Kara Seas ◽

The Arctic Region

The article provides an overview and analysis of seismicity within the boundaries of the Arctic region for 2014, a description of seismic station networks and processing methods. The catalog of earthquakes in the Arctic region was compiled on the basis of catalogs of several organizations and seismological centers. In total, 452 earthquakes with ML≥1.5 are included in the earthquake catalog. Most of the earthquakes occurred in 2014, including all the strongest earthquakes, werelocated within the mid-ocean ridges of Mon, Knipovich and Gakkel. In the offshore territories, most of the earthquakes were confined to the Svalbard archipelago, in particular, to the seismically active zone in the Sturfjord strait. The renewal of instrumental seismological observations in 2011 (station ZFI) on Alexandra Land Island in the Franz Josef Land archipelago made it possible to record weak earthquakes in the north of the shelf of the Barents and Kara Seas. For seven earthquakes, the focal me-chanism parameters are presented according to Global CMT catalog.

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Nuclear icebreaker fleet and power supply on the basis of floating power units

Voprosy regionalnoj ekonomiki ◽

10.21499/2078-4023-2018--4-110-113 ◽

2018 ◽

Vol 35 (4) ◽

pp. 110-113

Author(s):

V. A. Tupchienko ◽

H. G. Imanova

Keyword(s):

Foreign Policy ◽

Power Supply ◽

Nuclear Power ◽

Arctic Region ◽

Nuclear Industry ◽

The Arctic ◽

Far North ◽

The Arctic Region

The article deals with the problem of the development of the domestic nuclear icebreaker fleet in the context of the implementation of nuclear logistics in the Arctic. The paper analyzes the key achievements of the Russian nuclear industry, highlights the key areas of development of the nuclear sector in the Far North, and identifies aspects of the development of mechanisms to ensure access to energy on the basis of floating nuclear power units. It is found that Russia is currently a leader in the implementation of the nuclear aspect of foreign policy and in providing energy to the Arctic region.

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