scholarly journals 7Be, 210Pbatm and 137Cs in Snow Deposits in the Arctic Part of Western Siberia (Yamal-Nenets Autonomous District)

Atmosphere ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 825
Author(s):  
Kseniya Mezina ◽  
Mikhail Melgunov ◽  
Dmitriy Belyanin

Radioactive isotopes (7Be, 210Pbatm and 137Cs) are used as indicators of processes associated with the transfer of matter from the atmosphere. Studying snow cover can provide information about the seasonal deposition flux of the isotopes to the Earth’s surface over the entire period of snow accumulation. The purpose of this study is to identify the features of 7Be, 210Pbatm and 137Cs deposition with the atmospheric precipitation in winter in the Arctic part of Western Siberia and to study the contribution of the particulate fractions of suspended matter in snow water to the total content of the radionuclides in samples of integrated seasonal snowfall. Snow samples were taken over a wide area along the highways around Novy Urengoy in April 2019. The suspended matter in snow samples was divided into three fractions. The isotopic composition was determined by high-resolution semiconductor gamma-spectrometry. The seasonal deposition flux of 7Be and 210Pbatm in the winter at the time of sampling averaged 58.7 and 25.2 Bq m−2 season−1, respectively. The average specific activity of 7Be and 210Pbatm in the snow water was 248.0 and 104.5 mBq L−1. The deposition flux of 137Cs from the atmosphere was low compared to 7Be and 210Pbatm and did not exceed 0.39 Bq m−2 season−1 at all sampling points. This indicates an insignificant modern flux of the radionuclide from the atmosphere. The separation of suspended matter in snow water by particulate fractions shows that the studied isotopes are present in all the extracted fractions: >3, 0.45–3 and <0.45 μm. The main part of 210Pbatm in all studied samples is in the coarse-grained fraction >3 μm. Most 7Be is contained in finely dispersed aerosols, colloids, or a dissolved component (where the fraction <0.45 μm). A significant increase in the contribution of coarse-grained fractions of suspended matter in snow water to the total activity of 7Be in snow precipitation was observed in territories with a higher anthropogenic impact.

Geologos ◽  
2015 ◽  
Vol 21 (1) ◽  
pp. 71-78 ◽  
Author(s):  
Vera M. Podobina

Abstract The present paper discusses foraminiferal assemblages and biozones established on the basis of studies of samples from ten borehole sequences of the Khanty-Mansiysk Horizon in the Samotlor area of the northern palaeobiogeographical district of western Siberia (Russia). In this region, middle and late Albian foraminiferal assemblages were first distinguished in western Siberia. Levels from which these assemblages have been recovered, are here referred to the following foraminiferal zones, the Ammobaculites fragmentarius-Gaudryinopsis filiformis Zone (middle Albian) and the Ammotium braunsteini-Verneuilinoides borealis assanoviensis Zone (upper Albian). Zonal assemblages are dominated by representatives of the orders Ammodiscida, Textulariida and Ataxophragmiida. Species of the ataxophragmiid genera Verneuilinoides, Pseudoverneuilina and Gaudryinopsis are the most characteristic, inclusive of several key index forms. Foraminiferal tests consist of agglutinated quartz-silica, the wall microstructure being almost exclusively medium and coarse grained. In specific composition, the Albian assemblages from the Samotlor area are similar to those from Transuralia (Russia) and to the Canadian Province, which, together with West-Siberian Province, forms the Arctic palaeobiogeographical realm


Author(s):  
G. A. Leonova ◽  
◽  
M. S. Melgunov ◽  
K. A. Mezina ◽  
A. E. Maltsev ◽  
...  

Specific activities of natural (7Be, 210Pb) and technogenic (137Cs) radioisotopes in the suspended matter of snow melted water have been determined and the density of their fallout on the surface of the Sherstobitovo and Ubinskoye peat bogs of the Baraba forest-steppe at the points of snow flow in winter period is estimated. It has been established that the main concentrator of the 7Be radioisotope is a finely dispersed fraction of suspended matter (<0.45 μm), consisting of colloids and dissolved component, 210Pbatm is a coarse-grained fraction (> 3 μm), consisting of dust particles. On the example of vertical profile of the Sherstobitovo peat bog, the first data on the distribution of natural (238U, 210Pb, 226Ra, 40K) and technogenic (137Cs) isotopes were obtained for peat bogs of forest –steppe zone of the Western Siberia. Both 226Ra and 238U show the same pattern of vertical distribution that is also usual for 137Cs and 40K. The increase of activity of these radionuclides is observed in the horizon of 6-12 cm as well as in the lower section part (25-35 cm). According to our assumption it is due to the same processes. Migration of 37Cs deep into peat accumulation is significantly determined by moor water fluctuations in the seasonal and long-term cycle, and it is closely related to the microrelief of bog surface. Besides, 137Cs, being a geochemical analogue of the 40K biophile, is pulled up from the underlying peat horizons by plant roots during the dry season. An additional contribution to the high activity of 137Cs in upper horizons is probably due to the input of 137Cs to the surface of the Sherstobitovo peat bog as a result of peat and forest fires.


Atmosphere ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 363
Author(s):  
George Duffy ◽  
Fraser King ◽  
Ralf Bennartz ◽  
Christopher G. Fletcher

CloudSat is often the only measurement of snowfall rate available at high latitudes, making it a valuable tool for understanding snow climatology. The capability of CloudSat to provide information on seasonal and subseasonal time scales, however, has yet to be explored. In this study, we use subsampled reanalysis estimates to predict the uncertainties of CloudSat snow water equivalent (SWE) accumulation measurements at various space and time resolutions. An idealized/simulated subsampling model predicts that CloudSat may provide seasonal SWE estimates with median percent errors below 50% at spatial scales as small as 2° × 2°. By converting these predictions to percent differences, we can evaluate CloudSat snowfall accumulations against a blend of gridded SWE measurements during frozen time periods. Our predictions are in good agreement with results. The 25th, 50th, and 75th percentiles of the percent differences between the two measurements all match predicted values within eight percentage points. We interpret these results to suggest that CloudSat snowfall estimates are in sufficient agreement with other, thoroughly vetted, gridded SWE products. This implies that CloudSat may provide useful estimates of snow accumulation over remote regions within seasonal time scales.


2005 ◽  
Vol 51 (175) ◽  
pp. 637-654 ◽  
Author(s):  
Vladimir B. Aizen ◽  
Elena Aizen ◽  
Koji Fujita ◽  
Stanislav A. Nikitin ◽  
Karl J. Kreutz ◽  
...  

AbstractIn the summers of 2001 and 2002, glacio-climatological research was performed at 4110–4120 m a.s.l. on the Belukha snow/firn plateau, Siberian Altai. Hundreds of samples from snow pits and a 21 m snow/firn core were collected to establish the annual/seasonal/monthly depth–accumulation scale, based on stable-isotope records, stratigraphic analyses and meteorological and synoptic data. The fluctuations of water stable-isotope records show well-preserved seasonal variations. The δ18O and δD relationships in precipitation, snow pits and the snow/firn core have the same slope to the covariance as that of the global meteoric water line. The origins of precipitation nourishing the Belukha plateau were determined based on clustering analysis of δ18O and d-excess records and examination of synoptic atmospheric patterns. Calibration and validation of the developed clusters occurred at event and monthly timescales with about 15% uncertainty. Two distinct moisture sources were shown: oceanic sources with d-excess <12‰, and the Aral–Caspian closed drainage basin sources with d-excess >12‰. Two-thirds of the annual accumulation was from oceanic precipitation, of which more than half had isotopic ratios corresponding to moisture evaporated over the Atlantic Ocean. Precipitation from the Arctic/Pacific Ocean had the lowest deuterium excess, contributing one-tenth to annual accumulation.


2002 ◽  
Vol 35 ◽  
pp. 181-186 ◽  
Author(s):  
Alexey A. Ekaykin ◽  
Vladimir Ya. Lipenkov ◽  
Narcisse I. Barkov ◽  
Jean Robert Petit ◽  
Valerie Masson-Delmotte

AbstractContinuous, detailed isotope (δD and δ18O) profiles were obtained from eight snow pits dug in the vicinity of Vostok station, Antarctica, during the period 1984– 2000. In addition, snow samples taken along the 1km long accumulation-stake profile were measured to determine spatial variability in isotope composition of recent snow. the stacked δD time series spanning the last 55 years shows only weak correlation with the mean annual air temperature recorded at Vostok station. Significant oscillations of both snow accumulation and snow isotope composition with the periods 2.5, 5, 20 and, possibly, ~102 years observed at single points are interpreted in terms of drift of snow-accumulation waves of various scales on the surface of the ice sheet.


2021 ◽  
Author(s):  
V.A. Marinov ◽  
A.V. Khramtsova ◽  
A.E. Igolnikov ◽  
O.S. Urman ◽  
E.A. Potapova ◽  
...  

Geophysics ◽  
2016 ◽  
Vol 81 (1) ◽  
pp. WA183-WA193 ◽  
Author(s):  
W. Steven Holbrook ◽  
Scott N. Miller ◽  
Matthew A. Provart

The water balance in alpine watersheds is dominated by snowmelt, which provides infiltration, recharges aquifers, controls peak runoff, and is responsible for most of the annual water flow downstream. Accurate estimation of snow water equivalent (SWE) is necessary for runoff and flood estimation, but acquiring enough measurements is challenging due to the variability of snow accumulation, ablation, and redistribution at a range of scales in mountainous terrain. We have developed a method for imaging snow stratigraphy and estimating SWE over large distances from a ground-penetrating radar (GPR) system mounted on a snowmobile. We mounted commercial GPR systems (500 and 800 MHz) to the front of the snowmobile to provide maximum mobility and ensure that measurements were taken on pristine snow. Images showed detailed snow stratigraphy down to the ground surface over snow depths up to at least 8 m, enabling the elucidation of snow accumulation and redistribution processes. We estimated snow density (and thus SWE, assuming no liquid water) by measuring radar velocity of the snowpack through migration focusing analysis. Results from the Medicine Bow Mountains of southeast Wyoming showed that estimates of snow density from GPR ([Formula: see text]) were in good agreement with those from coincident snow cores ([Formula: see text]). Using this method, snow thickness, snow density, and SWE can be measured over large areas solely from rapidly acquired common-offset GPR profiles, without the need for common-midpoint acquisition or snow cores.


2016 ◽  
Vol 5 (1) ◽  
pp. 163-179 ◽  
Author(s):  
Leena Leppänen ◽  
Anna Kontu ◽  
Henna-Reetta Hannula ◽  
Heidi Sjöblom ◽  
Jouni Pulliainen

Abstract. The manual snow survey program of the Arctic Research Centre of the Finnish Meteorological Institute (FMI-ARC) consists of numerous observations of natural seasonal taiga snowpack in Sodankylä, northern Finland. The easily accessible measurement areas represent the typical forest and soil types in the boreal forest zone. Systematic snow measurements began in 1909 with snow depth (HS) and snow water equivalent (SWE). In 2006 the manual snow survey program expanded to cover snow macro- and microstructure from regular snow pits at several sites using both traditional and novel measurement techniques. Present-day snow pit measurements include observations of HS, SWE, temperature, density, stratigraphy, grain size, specific surface area (SSA) and liquid water content (LWC). Regular snow pit measurements are performed weekly during the snow season. Extensive time series of manual snow measurements are important for the monitoring of temporal and spatial changes in seasonal snowpack. This snow survey program is an excellent base for the future research of snow properties.


Georesursy ◽  
2019 ◽  
Vol 21 (3) ◽  
pp. 125-135
Author(s):  
Valery I. Isaev ◽  
Galina A. Lobova ◽  
Alexander N. Fomin ◽  
Valery I. Bulatov ◽  
Stanislav G. Kuzmenkov ◽  
...  

The possibilities of Geothermy as a geophysical method are studied to solve forecast and prospecting problems of Petroleum Geology of the Arctic regions and the Paleozoic of Western Siberia. Deep heat flow of Yamal fields, whose oil and gas potential is associated with the Jurassic-Cretaceous formations, and the fields of Tomsk Region, whose geological section contents deposits in the Paleozoic, is studied. The method of paleotemperature modeling was used to calculate the heat flow density from the base of a sedimentary section (by solving the inverse problem of Geothermy). The schematization and mapping of the heat flow were performed, taking into account experimental determinations of the parameter. Besides, the correlation of heat flow features with the localization of deposits was revealed. The conceptual and factual basis of research includes the tectonosedimentary history of sedimentary cover, the Mesozoic-Cenozoic climatic temperature course and the history of cryogenic processes, as well as lithologic and stratigraphic description of the section, results of well testing, thermometry and vitrinite reflectivity data of 20 deep wells of Yamal and 37 wells of Ostanino group of fields of Tomsk region. It was stated that 80 % of known Yamal deposits correlate with anomalous features of the heat flow. Bovanenkovskoe and Arkticheskoe fields are located in positive anomaly zones. 75 % of fields of Ostanino group relate to anomalous features of the heat flow. It is shown that the fields, which are characterized by existence of commercial deposits in the Paleozoic, are associated with the bright gradient zone of the heat flow. The forecast of commercial inflows in the Paleozoic for Pindzhinskoe, Mirnoe and Rybalnoe fields is given. The correlation between the intensity of naftidogenesis and the lateral inhomogeneity of the deep heat flow is characterized as a probable fundamental pattern for Western Siberia.


2021 ◽  
Vol 100 (6) ◽  
pp. 610-616
Author(s):  
Sergey V. Andronov ◽  
Andrey A. Lobanov ◽  
Irina V. Kobel’kova ◽  
Andrey I. Popov ◽  
Luo Luo ◽  
...  

Introduction. The nutrition of the Nenets in the Arctic zone of Western Siberia is mainly based on traditional products (raw (thermally unprocessed) local fish and venison), which is the most important factor of survival in the Arctic. Storing up food products for an extended period is not relevant for the Nenets. Climate change and industrial development in the Arctic primarily affect the seasonality of consumption. Changing the calendar of fish and venison harvesting leads to greater use of imported and canned local food, increasing the length of the periods when local food completely disappears from the diet of the Nenets. Material and methods. During the expeditions to the national villages of the Yamal-Nenets Autonomous Okrug, cross-sectional screening studies were performed, in which 985 Nenets people took part. Nutritional analysis was conducted using the questionnaire method based on an album of portions and dishes. Retrospective information was collected on the seasonality of consumption of reindeer products and local fisheries (the length of the period when unserved fish and venison are available). Results. The consumption of reindeer and river fishery products is seasonal. The duration of the season of venison consumption was from 150±14.0 to 180±21.0, and raw fish - from 120±14.0 to 200±21.0 days. Despite the high level of consuming reindeer products per season, the average annual consumption of venison by Nenets in the Arctic zone of Western Siberia was 240 g/day/person that is less than in the central regions of the Russian Federation and industrially developed countries. In the studied area, the average annual consumption of fish (171.5 g/day/person) is three times higher than the average consumption in the Russian Federation. However, increased consumption of traditional food is typically only during the season of fishing or slaughtering reindeer. The average annual consumption reduced; during the off-season, the share of easily digestible carbohydrates in the diet increased. Conclusion. The creation of fish and venison stocks in villages and their year-round sale to the population is a necessary step in ensuring the food security of the Nenets people.


Sign in / Sign up

Export Citation Format

Share Document