Seasonal variability of the Rossby radius deformation in the Hornsund fjord

Author(s):  
Anna Przyborska ◽  
Daniel Rak ◽  
Agnieszka Strzelewicz ◽  
Jaromir Jakacki ◽  
Maciej Muzyka

<p>The Earth's rotation affects the water circulation in the Arctic fjords. It can be described by means of the baroclinic Rossby radius deformation (R<sub>1</sub>) expressed as the ratio of the internal wave velocity to the Coriolis parameter.</p><p>The influence of the rotational effects on the water‐mass distribution depends on the width of the fjord in relation to the baroclinic radius of deformation (Gilbert, 1983). Most often the Rossby radius deformation in the Arctic fjords is 2-3 times smaller than the width of the fjord entrance, which allows the rotation of water masses within such fjords (Cottier, 2010). Such a situation exists in the small, western fjord of Svalbard - Hornsund, where the rotation makes the Atlantic and the Arctic waters flow from the shelf into the fjord along the southern bank and flow out of the fjord along the northern bank. The impact of the Coriolis force on the Hornsund environment was observed in a sedimentary record from the last century (Pawłowska et al. 2017). Literature estimates indicate that Hornsund is a typical fjord with an internal baroclinic Rossby radius between 3.5 and 6 km (Cottier, 2005, Nilsen, 2008).</p><p>The spatial and seasonal variation of the R<sub>1</sub> in the Hornsund fjord was carried out based on data from the numerical model (Jakacki et al. 2017) for the period 2005-2010 and for the selected actual data collected during the AREX survey campaigns.  The analysis of the actual data and model data confirms the seasonal variability of the vertical water structure in the fjord, which leads to cyclic changes of the vertical <strong>Brunta-Vaisali </strong>frequency structure and consequently to seasonal variability of R<sub>1</sub>. In the Hornsund fjord seasonality strongly influences the Rossby radius, which reaches maximum values in summertime and minimum values in wintertime. Moreover, R<sub>1</sub> values can be different even at points close to each other.  The values of the baroclinic Rossby radius of deformation also differ depending on the adopted calculation method.<br><br>Calculations were carried out at the Academic Computer Centre in Gdańsk.</p><p> </p><p> </p>

Eos ◽  
2021 ◽  
Vol 102 ◽  
Author(s):  
Andrew Chapman
Keyword(s):  
Sea Ice ◽  

A new study demonstrates the benefits of crowdsourcing science using sailboats to better understand the impact of melting sea ice in the Arctic.


2014 ◽  
Vol 14 (9) ◽  
pp. 13817-13867 ◽  
Author(s):  
L. J. Kramer ◽  
D. Helmig ◽  
J. F. Burkhart ◽  
A. Stohl ◽  
S. Oltmans ◽  
...  

Abstract. Measurements of atmospheric NOx (NOx = NO + NO2), peroxyacetyl nitrate (PAN), NOy and non-methane hydrocarbons (NMHC) were taken at the GEOSummit Station, Greenland (72.34° N, 38.29° W, 3212 m.a.s.l) from July 2008 to July 2010. The data set represents the first year-round concurrent record of these compounds sampled at a high latitude Arctic site in the free troposphere. Here, the study focused on the seasonal variability of these important ozone (O3) precursors in the Arctic free troposphere and the impact from transported anthropogenic and biomass burning emissions. Our analysis shows that PAN is the dominant NOy species in all seasons at Summit, varying from 49% to 78%, however, we find that odd NOy species (odd NOy = NOy − PAN-NOx) contribute a large amount to the total NOy speciation with monthly means of up to 95 pmol mol−1 in the winter and ∼40 pmol mol−1 in the summer, and that the level of odd NOy species at Summit during summer is greater than that of NOx. We hypothesize that the source of this odd NOy is most likely alkyl nitrates from transported pollution, and photochemically produced species such as HNO3 and HONO. FLEXPART retroplume analysis and tracers for anthropogenic and biomass burning emissions, were used to identify periods when the site was impacted by polluted air masses. Europe contributed the largest source of anthropogenic emissions during the winter and spring months, with up to 82% of the simulated anthropogenic black carbon originating from this region between December 2009 and March 2010, whereas, North America was the primary source of biomass burning emissions. Polluted air masses were typically aged, with median transport times to the site from the source region of 11 days for anthropogenic events in winter, and 14 days for BB plumes. Overall we find that the transport of polluted air masses to the high altitude Arctic typically resulted in high variability in levels of O3 and O3 precursors. During winter, plumes originating from mid-latitude regions and transported in the lower troposphere to Summit often result in lower O3 mole fractions than background levels. However, plumes transported at higher altitudes can result in positive enhancements in O3 levels. It is therefore likely that the air masses transported in the mid-troposphere were mixed with air from stratospheric origin. Similar enhancements in O3 and its precursors were also observed during periods when FLEXPART indicated that biomass burning emissions impacted Summit. The analysis of anthropogenic events over summer show that emissions of anthropogenic origin have a greater impact on O3 and precursor levels at Summit than biomass burning sources during the measurement period, with enhancements above background levels of up to 16 nmol mol−1 for O3 and 237 pmol mol−1 and 205 pmol mol−1, 28 pmol mol−1 and 1.0 nmol mol−1 for NOy, PAN, NOx and ethane, respectively.


2015 ◽  
Vol 15 (12) ◽  
pp. 6827-6849 ◽  
Author(s):  
L. J. Kramer ◽  
D. Helmig ◽  
J. F. Burkhart ◽  
A. Stohl ◽  
S. Oltmans ◽  
...  

Abstract. Measurements of atmospheric nitrogen oxides NOx (NOx = NO + NO2), peroxyacetyl nitrate (PAN), NOy, and non-methane hydrocarbons (NMHC) were taken at the Greenland Environmental Observatory at Summit (GEOSummit) station, Greenland (72.34° N, 38.29° W; 3212 m a.s.l.), from July 2008 to July 2010. The data set represents the first year-round concurrent record of these compounds sampled at a high latitude Arctic site. Here, the study focused on the seasonal variability of these important ozone (O3) precursors in the Arctic troposphere and the impact from transported anthropogenic and biomass burning emissions. Our analysis shows that PAN is the dominant NOy species in all seasons at Summit, varying from 42 to 76 %; however, we find that odd NOy species (odd NOy = NOy − PAN − NOx) contribute a large amount to the total NOy speciation. We hypothesize that the source of this odd NOy is most likely alkyl nitrates and nitric acid (HNO3) from transported pollution, and photochemically produced species such as nitrous acid (HONO). FLEXPART retroplume analyses and black carbon (BC) tracers for anthropogenic and biomass burning (BB) emissions were used to identify periods when the site was impacted by polluted air masses. Europe contributed the largest source of anthropogenic emissions during the winter months (November–March) with 56 % of the total anthropogenic BC tracer originating from Europe in 2008–2009 and 69 % in 2009–2010. The polluted plumes resulted in mean enhancements above background levels up to 334, 295, 88, and 1119 pmol mol−1 for NOy, PAN, NOx, and ethane, respectively, over the two winters. Enhancements in O3 precursors during the second winter were typically higher, which may be attributed to the increase in European polluted air masses transported to Summit in 2009–2010 compared to 2008–2009. O3 levels were highly variable within the sampled anthropogenic plumes with mean ΔO3 levels ranging from −6.7 to 7.6 nmol mol−1 during the winter periods. North America was the primary source of biomass burning emissions during the summer; however, only 13 BB events were observed as the number of air masses transported to Summit, with significant BB emissions, was low in general during the measurement period. The BB plumes were typically very aged, with median transport times to the site from the source region of 14 days. The analyses of O3 and precursor levels during the BB events indicate that some of the plumes sampled impacted the atmospheric chemistry at Summit, with enhancements observed in all measured species.


2019 ◽  
Vol 16 (6) ◽  
pp. 50-59
Author(s):  
O. P. Trubitsina ◽  
V. N. Bashkin

The article is devoted to the consideration of geopolitical challenges for the analysis of geoenvironmental risks (GERs) in the hydrocarbon development of the Arctic territory. Geopolitical risks (GPRs), like GERs, can be transformed into opposite external environment factors of oil and gas industry facilities in the form of additional opportunities or threats, which the authors identify in detail for each type of risk. This is necessary for further development of methodological base of expert methods for GER management in the context of the implementational proposed two-stage model of the GER analysis taking to account GPR for the improvement of effectiveness making decisions to ensure optimal operation of the facility oil and gas industry and minimize the impact on the environment in the geopolitical conditions of the Arctic.The authors declare no conflict of interest


Author(s):  
S. A. Gorbanev ◽  
S. A. Syurin ◽  
N. M. Frolova

Introduction. Due to the impact of adverse working conditions and climate, workers in coal-mining enterprises in the Arctic are at increased risk of occupational diseases (OD).The aim of the study was to study the working conditions, causes, structure and prevalence of occupational diseases in miners of coal mines in the Arctic.Materials and methods. Th e data of social and hygienic monitoring “Working conditions and occupational morbidity” of the population of Vorkuta and Chukotka Autonomous District in 2007–2017 are studied.Results. It was established that in 2007–2017 years, 2,296 ODs were diagnosed for the first time in 1851 coal mines, mainly in the drifters, clearing face miners, repairmen and machinists of mining excavating machines. Most often, the ODs occurred when exposed to the severity of labor, fibrogenic aerosols and hand-arm vibration. The development of professional pathology in 98% of cases was due to design flaws of machines and mechanisms, as well as imperfections of workplaces and technological processes. Diseases of the musculoskeletal system (36.2%), respiratory organs (28.9%) and nervous system (22.5%) prevailed in the structure of professional pathology of miners of coal mines. Among the three most common nosological forms of OD were radiculopathy (32.1%), chronic bronchitis (27.7%) and mono-polyneuropathy (15.4%). In 2017, coal miners in the Arctic had a professional morbidity rate of 2.82 times higher than the national rates for coal mining.Conclusions. To preserve the health of miners of coal mining enterprises, technical measures to improve working conditions and medical interventions aimed at increasing the body’s resistance to the effects of harmful production and climatic factors are necessary.


Author(s):  
Sergei Soldatenko ◽  
Sergei Soldatenko ◽  
Genrikh Alekseev ◽  
Genrikh Alekseev ◽  
Alexander Danilov ◽  
...  

Every aspect of human operations faces a wide range of risks, some of which can cause serious consequences. By the start of 21st century, mankind has recognized a new class of risks posed by climate change. It is obvious, that the global climate is changing, and will continue to change, in ways that affect the planning and day to day operations of businesses, government agencies and other organizations and institutions. The manifestations of climate change include but not limited to rising sea levels, increasing temperature, flooding, melting polar sea ice, adverse weather events (e.g. heatwaves, drought, and storms) and a rise in related problems (e.g. health and environmental). Assessing and managing climate risks represent one of the most challenging issues of today and for the future. The purpose of the risk modeling system discussed in this paper is to provide a framework and methodology to quantify risks caused by climate change, to facilitate estimates of the impact of climate change on various spheres of human activities and to compare eventual adaptation and risk mitigation strategies. The system integrates both physical climate system and economic models together with knowledge-based subsystem, which can help support proactive risk management. System structure and its main components are considered. Special attention is paid to climate risk assessment, management and hedging in the Arctic coastal areas.


2019 ◽  
pp. 3-20
Author(s):  
V.N. Leksin

The impact on healthcare organization on the territory of Russian Arctic of unique natural and climatic, demographic, ethnic, settlement and professional factors of influencing the health of population, constantly or temporarily living on this territory is studied. The necessity is substantiated of various forms and resource provision with healthcare services such real and potential patients of Arctic medical institutions, as representatives of indigenous small peoples of the North, workers of mining and metallurgical industry, military personnel, sailors and shift workers. In this connection a correction of a number of All-Russian normative acts is proposed.


Atmosphere ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 454
Author(s):  
Andrew R. Jakovlev ◽  
Sergei P. Smyshlyaev ◽  
Vener Y. Galin

The influence of sea-surface temperature (SST) on the lower troposphere and lower stratosphere temperature in the tropical, middle, and polar latitudes is studied for 1980–2019 based on the MERRA2, ERA5, and Met Office reanalysis data, and numerical modeling with a chemistry-climate model (CCM) of the lower and middle atmosphere. The variability of SST is analyzed according to Met Office and ERA5 data, while the variability of atmospheric temperature is investigated according to MERRA2 and ERA5 data. Analysis of sea surface temperature trends based on reanalysis data revealed that a significant positive SST trend of about 0.1 degrees per decade is observed over the globe. In the middle latitudes of the Northern Hemisphere, the trend (about 0.2 degrees per decade) is 2 times higher than the global average, and 5 times higher than in the Southern Hemisphere (about 0.04 degrees per decade). At polar latitudes, opposite SST trends are observed in the Arctic (positive) and Antarctic (negative). The impact of the El Niño Southern Oscillation phenomenon on the temperature of the lower and middle atmosphere in the middle and polar latitudes of the Northern and Southern Hemispheres is discussed. To assess the relative influence of SST, CO2, and other greenhouse gases’ variability on the temperature of the lower troposphere and lower stratosphere, numerical calculations with a CCM were performed for several scenarios of accounting for the SST and carbon dioxide variability. The results of numerical experiments with a CCM demonstrated that the influence of SST prevails in the troposphere, while for the stratosphere, an increase in the CO2 content plays the most important role.


Water ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 202
Author(s):  
Meilian Chen ◽  
Ji-Hoon Kim ◽  
Sungwook Hong ◽  
Yun Kyung Lee ◽  
Moo Hee Kang ◽  
...  

Fjords in the high Arctic, as aquatic critical zones at the interface of land-ocean continuum, are undergoing rapid changes due to glacier retreat and climate warming. Yet, little is known about the biogeochemical processes in the Arctic fjords. We measured the nutrients and the optical properties of dissolved organic matter (DOM) in both seawater and sediment pore water, along with the remote sensing data of the ocean surface, from three West Svalbard fjords. A cross-fjord comparison of fluorescence fingerprints together with downcore trends of salinity, Cl−, and PO43− revealed higher impact of terrestrial inputs (fluorescence index: ~1.2–1.5 in seawaters) and glaciofluvial runoffs (salinity: ~31.4 ± 2.4 psu in pore waters) to the southern fjord of Hornsund as compared to the northern fjords of Isfjorden and Van Mijenfjorden, tallying with heavier annual runoff to the southern fjord of Hornsund. Extremely high levels of protein-like fluorescence (up to ~4.5 RU) were observed at the partially sea ice-covered fjords in summer, in line with near-ubiquity ice-edge blooms observed in the Arctic. The results reflect an ongoing or post-phytoplankton bloom, which is also supported by the higher levels of chlorophyll a fluorescence at the ocean surface, the very high apparent oxygen utilization through the water column, and the nutrient drawdown at the ocean surface. Meanwhile, a characteristic elongated fluorescence fingerprint was observed in the fjords, presumably produced by ice-edge blooms in the Arctic ecosystems. Furthermore, alkalinity and the humic-like peaks showed a general downcore accumulation trend, which implies the production of humic-like DOM via a biological pathway also in the glaciomarine sediments from the Arctic fjords.


2021 ◽  
Vol 9 (2) ◽  
pp. 317
Author(s):  
Dolors Vaqué ◽  
Julia A. Boras ◽  
Jesús Maria Arrieta ◽  
Susana Agustí ◽  
Carlos M. Duarte ◽  
...  

The ocean surface microlayer (SML), with physicochemical characteristics different from those of subsurface waters (SSW), results in dense and active viral and microbial communities that may favor virus–host interactions. Conversely, wind speed and/or UV radiation could adversely affect virus infection. Furthermore, in polar regions, organic and inorganic nutrient inputs from melting ice may increase microbial activity in the SML. Since the role of viruses in the microbial food web of the SML is poorly understood in polar oceans, we aimed to study the impact of viruses on prokaryotic communities in the SML and in the SSW in Arctic and Antarctic waters. We hypothesized that a higher viral activity in the SML than in the SSW in both polar systems would be observed. We measured viral and prokaryote abundances, virus-mediated mortality on prokaryotes, heterotrophic and phototrophic nanoflagellate abundance, and environmental factors. In both polar zones, we found small differences in environmental factors between the SML and the SSW. In contrast, despite the adverse effect of wind, viral and prokaryote abundances and virus-mediated mortality on prokaryotes were higher in the SML than in the SSW. As a consequence, the higher carbon flux released by lysed cells in the SML than in the SSW would increase the pool of dissolved organic carbon (DOC) and be rapidly used by other prokaryotes to grow (the viral shunt). Thus, our results suggest that viral activity greatly contributes to the functioning of the microbial food web in the SML, which could influence the biogeochemical cycles of the water column.


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