scholarly journals On the accuracy of aurora visible boundaries in the OVATION Prime (PC) model

2021 ◽  
pp. 171-182
Author(s):  
А.В. Николаев ◽  
С.А. Долгачёва ◽  
С.А. Черняева
Keyword(s):  
Chemical Composition ◽  
Space Weather ◽  
Plasma Layer ◽  
Auroral Oval ◽  
Information Resources ◽  
The Arctic ◽  
Inner Magnetosphere ◽  
Aurora Borealis ◽  
Monitoring And Forecasting ◽  
Auroral Particle Precipitation

Оценка положения экваториальных границ аврорального овала при разных магнитосферных условиях, несёт в себе информацию о формирующихся плазменных структурах, глубине их проникновения во внутреннюю магнитосферу, движении внутренней границы плазменного слоя и т.д. Развитие алгоритмов определения положения видимой экваториальной границы аврорального овала является важной частью исследований, связанных с разработкой моделей химического состава ионосферы, моделей авроральных высыпаний частиц и оценки точности этих моделей. Немаловажную роль исследования полярных сияний (прогноз, интенсивность, положение) играют и для развития туристического сегмента в Арктике и информационных ресурсов служб мониторинга и прогноза космической погоды. В рамках исследования оценки точности положения видимых границ овала сияний в моделях авроральных высыпаний частиц была выбрана наземная наблюдательная сеть оптических камер всего неба проекта THEMIS, запущенная в 2008 г., и модифицированная модель OVATION Prime (PC), разработанная в отделе Геофизики ФГБУ «ААНИИ использующая в качестве входного параметра наземный индекс полярной шапки (PC-индекс). The location of the equatorial boundaries of the auroral oval under different magnetospheric conditions contains information about the forming plasma structures, the depth of their penetration into the inner magnetosphere, the motion of the inner boundary of the plasma layer, etc. The development of methods and algorithms for determining the position of the visible equatorial boundary of the auroral oval is an important part of research related to the development of models of the chemical composition of the ionosphere, models of auroral particle precipitation, and assessment of the accuracy of these models. Research of aurora borealis (forecast, intensity, position) also plays an important role for the development of the tourist segment in the Arctic and information resources of space weather monitoring and forecasting services.

Chemical Composition of Atmospheric Aerosol in the Arctic Region and Adjoining Seas along the Routes of Marine Expeditions in 2018–2019

2020 ◽  
Vol 33 (5) ◽  
pp. 480-489
Author(s):  
L. P. Golobokova ◽  
T. V. Khodzher ◽  
O. N. Izosimova ◽  
P. N. Zenkova ◽  
A. O. Pochyufarov ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Atmospheric Aerosol ◽  
Arctic Region ◽  
The Arctic ◽  
The Arctic Region

scholarly journals Effects of SO<sub>2</sub> oxidation on ambient aerosol growth in water and ethanol vapours

2005 ◽  
Vol 5 (3) ◽  
pp. 767-779 ◽  
Author(s):  
T. Petäjä ◽  
V.-M. Kerminen ◽  
K. Hämeri ◽  
P. Vaattovaara ◽  
J. Joutsensaari ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Sulphuric Acid ◽  
Cloud Condensation Nuclei ◽  
Aerosol Particles ◽  
The Arctic ◽  
Ambient Conditions ◽  
Similar Chemical ◽  
Ethanol Vapours ◽  
Hygroscopic Particles ◽  
Ultrafine Aerosol

Abstract. Hygroscopicity (i.e. water vapour affinity) of atmospheric aerosol particles is one of the key factors in defining their impacts on climate. Condensation of sulphuric acid onto less hygroscopic particles is expected to increase their hygrocopicity and hence their cloud condensation nuclei formation potential. In this study, differences in the hygroscopic and ethanol uptake properties of ultrafine aerosol particles in the Arctic air masses with a different exposure to anthropogenic sulfur pollution were examined. The main discovery was that Aitken mode particles having been exposed to polluted air were more hygroscopic and less soluble to ethanol than after transport in clean air. This aging process was attributed to sulphur dioxide oxidation and subsequent condensation during the transport of these particle to our measurement site. The hygroscopicity of nucleation mode aerosol particles, on the other hand, was approximately the same in all the cases, being indicative of a relatively similar chemical composition despite the differences in air mass transport routes. These particles had also been produced closer to the observation site typically 3–8 h prior to sampling. Apparently, these particles did not have an opportunity to accumulate sulphuric acid on their way to the site, but instead their chemical composition (hygroscopicity and ethanol solubility) resembled that of particles produced in the local or semi-regional ambient conditions.

scholarly journals Mineral Phase-Element Associations Based on Sequential Leaching of Ferromanganese Crusts, Amerasia Basin Arctic Ocean

Minerals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 460 ◽  
Author(s):  
Natalia Konstantinova ◽  
James Hein ◽  
Amy Gartman ◽  
Kira Mizell ◽  
Pedro Barrulas ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Arctic Ocean ◽  
The Arctic ◽  
Global Ocean ◽  
Residual Fraction ◽  
Ferromanganese Crusts ◽  
Sequential Leaching ◽  
Bottom Waters ◽  
Complementary Techniques ◽  
Chukchi Borderland

Ferromanganese (FeMn) crusts from Mendeleev Ridge, Chukchi Borderland, and Alpha Ridge, in the Amerasia Basin, Arctic Ocean, are similar based on morphology and chemical composition. The crusts are characterized by a two- to four-layered stratigraphy. The chemical composition of the Arctic crusts differs significantly from hydrogenetic crusts from elsewhere of global ocean by high mean Fe/Mn ratios, high As, Li, V, Sc, and Th concentrations, and high detrital contents. Here, we present element distributions through crust stratigraphic sections and element phase association using several complementary techniques such as SEM-EDS, LA-ICP-MS, and sequential leaching, a widely employed method of element phase association that dissolves mineral phases of different stability step-by-step: Exchangeable cations and Ca carbonates, Mn-oxides, Fe-hydroxides, and residual fraction. Sequential leaching shows that the Arctic crusts have higher contents of most elements characteristic of the aluminosilicate phase than do Pacific crusts. Elements have similar distributions between the hydrogenetic Mn and Fe phases in all the Arctic and Pacific crusts. The main host phases for the elements enriched in the Arctic crusts over Pacific crusts (Li, As, Th, and V) are the Mn-phase for Li and Fe-phase for As, Th, and V; those elements also have higher contents in the residual aluminosilicate phase. Thus, higher concentrations of Li, As, Th, and V likely occur in the dissolved and particulate phases in bottom waters where the Arctic crusts grow, which has been shown to be true for Sc, also highly enriched in the crusts. The phase distributions of elements within the crust layers is mostly consistent among the Arctic crusts, being somewhat different in element concentrations in the residual phase.

scholarly journals Measurement report: The chemical composition of and temporal variability in aerosol particles at Tuktoyaktuk, Canada, during the Year of Polar Prediction Second Special Observing Period

2021 ◽  
Vol 21 (18) ◽  
pp. 14199-14213
Author(s):  
John MacInnis ◽  
Jai Prakash Chaubey ◽  
Crystal Weagle ◽  
David Atkinson ◽  
Rachel Ying-Wen Chang
Keyword(s):  
Air Quality ◽  
Chemical Composition ◽  
Aerosol Particles ◽  
Road Dust ◽  
Quality Standard ◽  
The Arctic ◽  
Similar Range ◽  
The Government ◽  
Government Of Canada ◽  
Mass Concentrations

Abstract. The chemical composition, sources, and concentrations of aerosol particles vary on a seasonal basis in the Arctic. While existing research has focused on understanding the occurrence of aerosol particles during the Arctic winter and spring, less is known of their occurrence during the Arctic summer. In this study, atmospheric aerosol particle chemical composition and concentration were determined during July–September 2018 at Tuktoyaktuk, NT, Canada (69.4∘ N, 133.0∘ W), to coincide with the Year of Polar Prediction's Second Special Observing Period in the Arctic. The chemical composition of fine (PM2.5) and coarse (PM10–2.5) aerosol filter samples suggests the ocean, mineral and/or road dust, and combustion were sources of the sampled aerosol particles. Mass concentrations of PM2 and PM10, estimated from optical particle counter measurements, remained within a similar range during the study. However, elevated mass concentrations coincided with a festival in the community of Tuktoyaktuk, suggesting local human activity was an important source of aerosol particles. Mass concentrations of PM2, which promote negative health effects in humans, were significantly lower at Tuktoyaktuk than the national air quality standard recommended by the government of Canada. These measurements provide an important baseline to compare with future measurements associated with the assessment of aerosol chemistry and air quality in the Arctic.

Space Weather Phenomenon of Polar Ionosphere Over the Arctic Region

2021 ◽  
pp. 325-341
Author(s):  
A.K. Gwal ◽  
Suryanshu Choudhary ◽  
Himanshu Chaurasia
Keyword(s):  
Space Weather ◽  
Arctic Region ◽  
The Arctic ◽  
Polar Ionosphere ◽  
Weather Phenomenon ◽  
The Arctic Region

scholarly journals Tracking patchy pulsating aurora through all-sky images

2017 ◽  
Vol 35 (4) ◽  
pp. 777-784 ◽  
Author(s):  
Eric Grono ◽  
Eric Donovan ◽  
Kyle R. Murphy
Keyword(s):  
Time History ◽  
Image Data ◽  
Auroral Oval ◽  
Automatic Identification ◽  
Inner Magnetosphere ◽  
Wide Range ◽  
History Of ◽  
Initial Results ◽  
Automatic Technique

Abstract. Pulsating aurora is frequently observed in the evening and morning sector auroral oval. While the precipitating electrons span a wide range of energies, there is increasing evidence that the shape of pulsating auroral patches is controlled by structures in near-equatorial cold plasma; these patches appear to move with convection, for example. Given the tremendous and rapidly increasing amount of auroral image data from which the velocity of these patches can be inferred, it is timely to develop and implement techniques for the automatic identification of pulsating auroral patch events in these data and for the automatic determination of the velocity of individual patches from that data. As a first step towards this, we have implemented an automatic technique for determining patch velocities from sequences of images from the Time History of Events and Macroscale Interactions during Substorms (THEMIS) all-sky imager (ASI) and applied it to many pulsating aurora events. Here we demonstrate the use of this technique and present the initial results, including a comparison between ewograms (east–west keograms) and time series of patch position as determined by the algorithm. We discuss the implications of this technique for remote sensing convection in the inner magnetosphere.

scholarly journals Spatial Distribution of Atmospheric Aerosol Physicochemical Characteristics in the Russian Sector of the Arctic Ocean

Atmosphere ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 1170
Author(s):  
Sergey Sakerin ◽  
Dmitry Kabanov ◽  
Valery Makarov ◽  
Viktor Pol’kin ◽  
Svetlana Popova ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Chemical Composition ◽  
Arctic Ocean ◽  
Black Carbon ◽  
Forest Fires ◽  
Barents Sea ◽  
The Arctic ◽  
The North ◽  
The Barents Sea ◽  
The Arctic Ocean

The results from studies of aerosol in the Arctic atmosphere are presented: the aerosol optical depth (AOD), the concentrations of aerosol and black carbon, as well as the chemical composition of the aerosol. The average aerosol characteristics, measured during nine expeditions (2007–2018) in the Eurasian sector of the Arctic Ocean, had been 0.068 for AOD (0.5 µm); 2.95 cm−3 for particle number concentrations; 32.1 ng/m3 for black carbon mass concentrations. Approximately two–fold decrease of the average characteristics in the eastern direction (from the Barents Sea to Chukchi Sea) is revealed in aerosol spatial distribution. The average aerosol characteristics over the Barents Sea decrease in the northern direction: black carbon concentrations by a factor of 1.5; particle concentrations by a factor of 3.7. These features of the spatial distribution are caused mainly by changes in the content of fine aerosol, namely: by outflows of smokes from forest fires and anthropogenic aerosol. We considered separately the measurements of aerosol characteristics during two expeditions in 2019: in the north of the Barents Sea (April) and along the Northern Sea Route (July–September). In the second expedition the average aerosol characteristics turned out to be larger than multiyear values: AOD reached 0.36, particle concentration up to 8.6 cm−3, and black carbon concentration up to 179 ng/m3. The increased aerosol content was affected by frequent outflows of smoke from forest fires. The main (99%) contribution to the elemental composition of aerosol in the study regions was due to Ca, K, Fe, Zn, Br, Ni, Cu, Mn, and Sr. The spatial distribution of the chemical composition of aerosols was analogous to that of microphysical characteristics. The lowest concentrations of organic and elemental carbon (OC, EC) and of most elements are observed in April in the north of the Barents Sea, and the maximal concentrations in Far East seas and in the south of the Barents Sea. The average contents of carbon in aerosol over seas of the Asian sector of the Arctic Ocean are OC = 629 ng/m3, EC = 47 ng/m3.

scholarly journals Interhemispheric asymmetries in the occurrence of magnetically conjugate sub-auroral polarisation streams

2005 ◽  
Vol 23 (4) ◽  
pp. 1371-1390 ◽  
Author(s):  
M. L. Parkinson ◽  
M. Pinnock ◽  
J. A. Wild ◽  
M. Lester ◽  
T. K. Yeoman ◽  
...  
Keyword(s):  
Electric Field ◽  
Auroral Oval ◽  
Particle Interactions ◽  
Magnetospheric Substorms ◽  
Polarisation Field ◽  
Energetic Ions ◽  
Inner Magnetosphere ◽  
Flux Tubes ◽  
Ion Drift ◽  
Magnetic Flux Tubes

Abstract. Earthward injections of energetic ions and electrons mark the onset of magnetospheric substorms. In the inner magnetosphere (L4), the energetic ions drift westward and the electrons eastward, thereby enhancing the equatorial ring current. Wave-particle interactions can accelerate these particles to radiation belt energies. The ions are injected slightly closer to Earth in the pre-midnight sector, leading to the formation of a radial polarisation field in the inner magnetosphere. This maps to a poleward electric field just equatorward of the auroral oval in the ionosphere. The poleward electric field is subsequently amplified by ionospheric feedback, thereby producing auroral westward flow channels (AWFCs). In terms of electric field strength, AWFCs are the strongest manifestation of substorms in the ionosphere. Because geomagnetic flux tubes are essentially equi-potentials, similar AWFC signatures should be observed simultaneously in the Northern and Southern Hemispheres. Here we present magnetically conjugate SuperDARN radar observations of AWFC activity observed in the pre-midnight sector during two substorm intervals including multiple onsets during the evening of 30 November 2002. The Northern Hemisphere observations were made with the Japanese radar located at King Salmon, Alaska (57, and the Southern Hemisphere observations with the Tasman International Geospace Environment Radar (TIGER) located at Bruny Island, Tasmania (55. LANL geosynchronous satellite observations of energetic ion and electron fluxes monitored the effects of substorms in the inner magnetosphere (L6). The radar-observed AWFC activity was coincident with activity observed at geosynchronous orbit, as well as westward current surges in the ionosphere observed using ground-based magnetometers. The location of AWFCs with respect to the auroral oval was inferred from FUV auroral images recorded on board the IMAGE spacecraft. DMSP SSIES ion drift measurements confirmed the presence of AWFCs equatorward of the auroral oval. Systematic asymmetries in the interhemispheric signatures of the AWFCs probably arose because the magnetic flux tubes were distorted at L shells passing close to the substorm dipolarisation region. Transient asymmetries were attributed to the development of nearby field-aligned potential drops and currents.

scholarly journals Chemical equilibrium of groundwater with minerals of the host rocks in Upper Jurassic sediments (Arctic regions of Western Siberia)

2019 ◽  
Vol 98 ◽  
pp. 01037 ◽  
Author(s):  
Dmitry A. Novikov
Keyword(s):  
Chemical Composition ◽  
Chemical Equilibrium ◽  
Western Siberia ◽  
Upper Jurassic ◽  
The Arctic ◽  
Geochemical Environment ◽  
Rock System ◽  
Arctic Regions ◽  
Host Rocks ◽  
Mineral Changes

The results of thermodynamic calculations for a water-rock system in the Upper Jurassic deposits of the Arctic regions of Western Siberia are presented. In the area under investigation the groundwaters have been identified with mineralization up to 63.3 g/L and various chemical composition and genesis. Despite the long interaction with the rock (150-160 ma) equilibrium with endogenous minerals (albite, microcline and anorthite) is practically not observed. At the same time, groundwaters are in equilibrium with clay minerals and micas, such as: Caand Na-montmorillonites, kaolinite, paragonite, margarite, illite, muscovite and Mg-chlorite. The establishment of a balance of groundwater with primary aluminosilicate minerals is also affected by interactions with carbonate minerals. The differences in composition of groundwater in equilibrium with certain aluminosilicates and carbonates indicate that the mineral changes are formed from a solution of a strictly defined chemical composition in an appropriate geochemical environment.

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