Ice and Snow (E-Journal) / Лёд и Снег
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Расчёт характеристик снежного покрова равнинных территорий с использованием модели локального тепловлагообмена SPONSOR и данных реанализа на примере Московской области
Get PDFThe technique for calculating the snow cover characteristics (a water equivalent and a snow cover thickness) with high spatial and time resolution on spacious plains is proposed. The model SPONSOR of local heat- and moisture exchange (Land-Surface Model, LSM) and data of reanalyses NCEP/DOE and ECMWF ERA-Interim were used for calculations. The above characteristics of the snow cover on the test area of the Moscow region were calculated using this method over the period 1979–1996. The results were compared with actual data of the snow gauge stations and with data on snow cover, derived directly from reanalysis. The data from the NCEP/DOE reanalysis did not show satisfactory agreement with data of the observations for both the water equivalent and the thickness (Fig. 1, б and Fig. 2, б): deviations reached 60–70%. Monthly mean values of snow water equivalent from the ERA-Interim reanalysis were in a good agreement with the observations, but the snow thicknesses were reproduced much worse. At the same time, using the LSM SPONSOR with input meteorological data from the reanalyses allowed obtaining the snow cover characteristics which were in a good agreement with data of the observations for both the monthly means and individual daily values. The correlation coefficients with the data of snow gauge surveys increased, on the average, up to 0.83–0.89 for the water equivalent, and up to 0.85–0.91 for the snow depth (see the Тable in the text). Especially good results were obtained when meteorological data from the ERA-Interim reanalysis were used together with the LSM SPONSOR (Fig. 1, д and Fig. 2, д). It allows us to conclude that meteorological data from the ERA-Interim reanalysis together with data of regular observational network can be used as an additional source of information for calculations of the snow characteristics. This conclusion is especially important for areas with sparse network of regular observations.Предложена методика расчёта характеристик снежного покрова с высоким пространственным и временным разрешением с использованием модели локального тепловлагообмена (Land-Surface Model, LSM) SPONSOR и метеоданных реанализов NCEP/DOE и ECMWF ERA-Interim. Выполнены расчёты для тестового региона Московской области за период 1979–1996 гг. и проведено сравнение с данными наблюдений и реанализа. Данные о снежном покрове из реанализа существенно отличаются от данных наблюдений. Использование модели SPONSOR с входными метеоданными, взятыми из реанализа ECMWF ERA-Interim, позволяет получить характеристики снежного покрова с высоким пространственным и временным разрешением, которые хорошо согласуются с данными наблюдений
Система дистанционного мониторинга снеговой нагрузки на кровле зданий
Get PDFObtaining actual data on a change in the value of snow load for a snowfall is an important task the solution of which is usually neglected. The purpose of the work was to obtain a data on dynamics of the snow load change on a roof for a snowfall. A system for remote monitoring of the snow load was developed for this purpose. This system allows continuous gathering and transmission of the data on the snow load change from a unit of area. Obtaining this information gives an indication of the size of snow loading and dynamics of the snow accumulation during snowfall. The developed system provides continuous collection and transmission of data about the changing snow load per unit area. This information makes possible judging values of the snow load and its dynamics during a snowfall. Using of this system allows monitoring of snow accumulation during a snowfall. Discreteness of the system is 1 minute, and the sensitivity to the load change is 50 g. The platform is designed for a load less than 100 kg. When a snowfall ends the platform should be cleaned. In 2015, the system has been just tested, but in future we plan to use the system without cleaning for the whole snow season. In this connection, the more powerful sensors will be used. The system consists of a rectangular platform with an area of 1 m2, and it is equipped with four load cells «TOQUES» BBA at the corners. It was used for two months from late January to mid-March. In total, nine snowfalls were observed. In the winter season of 2014/15, increases of snow loads changed within the range of 10–100 kg/m2. Analysis of the data shows that the maximum snow load exerted on the roof takes place at a snowfall peak, after that it decreases under the influence of external factors. Three main factors influencing formation of the snow loads on a flat roof are as follows: the quantity of solid precipitation, the snow melting, and redistribution of snow by wind. Using of the system allows obtaining actual values of snow load on roofs of buildings instead of data calculated from the snow weight on the ground. These values can be then used to correct standards for the snow loads.Разработана система дистанционного мониторинга снеговой нагрузки на горизонтальную поверхность, которая представляет собой весовую платформу, оснащённую тензодатчиками и подключённую к подсистеме аналого-цифрового преобразования данных с передачей их на компьютер. Анализ данных, полученных на территории г. Южно-Сахалинск зимой 2014/15 г., показал, что максимальная нагрузка на поверхность кровли зданий во время снегопада может существенно превышать среднюю нагрузку, оценённую за весь сезон
К расчёту опреснения минерализованного пористого льда при таянии
Get PDFThe results obtained in this work demonstrate that dynamics of desalination of porous ice depends on a mobility of ions of salts, and the mobility is determined by the diffusion coefficient. The ice was made by freezing of mineralized water of different chemical composition. Model calculations of average mineralization of the porous ice at its thawing were made, and the ion concentrations of different salts were defined. Values of the diffusion coefficients of the salt ions in the film of brine ice pellets were obtained by means of comparison of results of measurements and calculations of dynamics of content of the salt ions in a porous ice at its thawing. The diffusion coefficient of ions Na+, Cl−, SO4 2− is by order of magnitude larger than that of Ca2+ and by two orders of magnitudethan HCO3 −. This results in that the content of ions Na+, Cl−, SO42− decreases in porous ice at its thawing 3 times faster than the content of the ions Ca2+. Basing on analysis of chemical composition of drainage water in some regions in Russia a possibility to desalinate the porous ice formed during the winter sprinkling is demonstrated.Рассмотрена динамика опреснения пористого льда, намороженного из минерализованной воды разного химического состава. Выполнены модельные расчёты минерализации пористого льда при таянии и концентрации в нём ионов различных солей. Путём сравнения измеренной динамики содержания ионов солей в пористом льду при таянии и расчётов определены коэффициенты диффузии ионов солей в плёнке «рассола» ледяных гранул. На основе анализа химического состава дренажных вод в некоторых районах России показана возможность применения опреснения пористого льда, образованного при зимнем дождевании
Ледниковая трагедия
Get PDFReview on the book written by V.M. Kotlyakov, O.V. Rototaeva, G.A. Nosenko, L.V. Desinov, N.I. Osokin, R.A. Chernov «Karmadon catastrophe: what happened and what we should wait for in future». Мoscow: Publishing House «Kodeks», 2014. 184 p.О книге В.М. Котлякова, О.В. Рототаевой, Г.А. Носенко, Л.В. Десинова, Н.И. Осокина, Р.А. Чернова «Кармадонская катастрофа: что случилось и чего ждать дальше». М.: Издательский дом «Кодекс», 2014. 184 с
Геохимические особенности подземных текстурообразующих льдов алмазоносных районов Западной Якутии
No full textThe unique research results of macro-components, trace elements and rare earth elements (REEs) in the structure-forming ground ice in sedimentary and igneous rocks of the diamond-bearing regions of Western Yakutia are presented. It has been found that deep freezing of sedimentary cover in the Yakutian diamond-bearing province gave rise to formation of ice-cement and intrusive ice in the sedimentary strata and kimberlites. Water-rock interaction before the glacial epoch and perennial cryogenesis in the Late Cenozoic resulted in current hydrogeochemical zonality in the diamond-bearing regions and stipulated formation of hydrocarbonate, sulfate-hydrocarbonate, chloride-hydrocarbonate, hydrocarbonate-chloride and chloride types of structure-forming ground ice. Ground ice is enriched in Li, B, Si, S, Br, Sr and is depleted in Sc, Ge, Y, Nb, Th. Concentration of the REE in ground ice is 2–4 orders of magnitude less than in kimberlites and sedimentary rocks, 1–2 orders of magnitude exceed the REE content in the ocean water and approximately equal to the REE content in the river waters. The profiles of REE distribution in the ground ice is characterized by the similar of Ʌ-shape, strongly marked Eu anomaly and approximately equal content of light and heavy REE
КЛИМАТИЧЕСКИЕ ПОСЛЕДСТВИЯ ЭКСПАНСИИ ПРЕСНЫХ ВОД В ГРЕНЛАНДСКОЕ МОРЕ И СЕВЕРНУЮ АТЛАНТИКУ
No full textIn second part of XX century there are three valuable salinity anomalies in North Atlantic, so-called «The Great Salinity Anomaly» (GSA), which can be characterized as a large, near-surface pool of fresher water [31–33, 36, 37]. There are GSA’70s, GSA’80s and GSA’90s. Dickson [37] described this event as one of dramatic and prolonged changes in ocean’s climate in XX century. In this paper, we have shown genesis of GSA’70s connected with ice production in Arctic flaw leads. Formation of GSAs’ in 1980s and 1990s has, at least, two main reasons. First is fresh water pools and huge amounts of ice carried out fromArcticBasin. The second one is recirculation of previous salinity anomaly inSubarcticBasin. Phenomenological model of climate change formation in polar and subpolar zone of North Hemisphere is presented in the paper. Examination conditions of previous GSA’s appearance and analysis of valuable fresh water intrusions in North Atlantic allow us to conclude that conditions for GSA’2010s are formed already and started to propagate inNorth Atlantic. For the first time we described GSA during its appearance, not post factum. Thus, we are standing at the break point of relatively long cooling inArctic.Во второй половине ХХ в. в Северной Атлантике отмечено три значимых аномалии распреснения поверхностных вод. В иностранной литературе они получили собственное имя – Великая соленосная аномалия (ВСА) [31–33, 36, 37]. Выделяют ВСА-1970-х, ВСА-1980-х и ВСА-1990-х годов. Р. Диксон [37] описал это явление как одно из наиболее резко и продолжительно влияющих на изменения климата океана в ХХ в. По мнению авторов настоящей статьи, генезис ВСА-1970-х связан с ледопродуктивностью арктических заприпайных полыней. В этой статье даётся феноменологическая модель формирования климатических изменений в зоне полярных и умеренных широт Северного полушария, обусловленных периодическими выбросами в Северную Атлантику аномально больших объёмов распреснённых вод из Северного Ледовитого океана. Делается вывод, что в настоящий момент уже сформировалась ВСА-2010-х и началось её распространение в Северной Атлантике. Впервые аномалия описывается не постфактум, а в момент зарождения. Таким образом, мы стоим на пороге достаточно длительного периода похолодания
Климатически обусловленные изменения вклада снега в формирование опасных гидрологических явлений на реках
No full textUnder current climate change the amount of snow plays a fundamental role in occurrence of hazardous hydrological events causing a steady growth in frequency of hazardous snow melt floods in mountain and piedmont areas in the south of Siberia and the Urals and coastal areas of the Far East. For these areas as well as for the Caucasus the following is also typical: greater influence of snow on occurrence of hazardous snow-rainfall floods, higher frequency of hazardous snowfalls and avalanching. Small amount of snow is one of the factors causing higher frequency of extreme lacks of water in summer low water periods on rivers of Asian Russia. On rivers of European Russia increased frequency of thaws and longer periods of snow melt reduce flood risk and enhance the role of snow in feeding underground waters to impede the growth in frequency of extreme lacks of water during low water periods.При современных изменениях климата снегозапасы, играющие важную роль в формировании экстремальных гидрологических явлений, служат причиной устойчивого повышения опасных наводнений в половодье на реках горных и предгорных районов юга Сибири и Урала, а также приморских и островных районов Дальнего Востока. Для многих регионов характерно также повышение доли снеговой составляющей в формировании опасных снегодождевых паводков. Вместе с тем малоснежность – одна из причин участившегося экстремального снижения уровня воды (экстремальных маловодий) в летнюю межень на реках азиатской территории. На реках Европейской части России увеличение повторяемости оттепелей и продолжительности снеготаяния уменьшает опасность наводнений и повышает роль снега в питании подземных вод, что снижает повторяемость экстремальных маловодий на реках в межень.
Геохимия снежного покрова таёжных и горных мерзлотных ландшафтов Якутии
No full textThe work is devoted to results of study the chemical composition of snow in mountain taiga and permafrost landscapes of Yakutia. We studied snow cover in different mountain-belt types of landscapes. The composition and calculated volumes of chemical elements and compounds are studied in snow. The chemical composition of snow in mountain taiga and permafrost landscape has remained relatively constant (hydrocarbonate chloride-bicarbonate or sodium-calcium, low sulfate content). The dominant influence on the chemical composition of snow at plains and mountain permafrost landscapes has a continental origin, mainly carbon compounds. In mountain desert, where there is predominantly regional transfer, along with the carbon significant role in atmospheric precipitation in cold season belongs to the nitrogen compounds, mainly ammonium. The total density of the entry of soluble and insoluble components in the form of snow decreases regularly with change of altitude. The distribution of trace elements in the snow cover is not a subject to altitudinal zonation. The maximum content of heavy metals (Mn, Cu, Pb, Cd), F, and Sr in the snow cover is observed in the landscapes of mountain woodlands and mountain tundra, where the route crossed research Sette-Daban metallogenic zone of stratiform Cu and Pb-Zn mineralization
Моделирование переноса загрязнений потоками в деформируемых руслах в условиях криолитозоны
No full textA common problem for the Arctic region is pollution by persistent organic compounds and other substances that have accumulated over the years in these areas. With temperature increasing, these substances can get out of the snow, ice, permafrost in the human environment. With climate warming and permafrost degradation the risk of toxic substances from the burial sites of chemical and radioactive waste increases. The work is devoted to research the pollution propagation in the rivers flowing in the permafrost taking into account the possible deformations of the channels caused by the melting of the permafrost with increasing temperature of the river flow water. We also consider the distribution of pollutants released during erosion of the coastal slopes, caused thermal erosion. Numerical experiments confirmed the quantitative assessment obtained from the field observations of the erosion rate increases with increasing temperature. Study the impact of thermal and mechanical erosion of the distribution of impurities led to the conclusion that as a result of the formation of taliks uniform flow conditions are violated, resulting in a non-stationary distribution of impurities. The increase in the volume of the test section of the river due to the appearance of cavities in the coastal slope leads to an increase in impurity concentration. Analysis of the results of modeling the spread of contamination during thawing sources in the frozen shores, demonstrated the relationship in the process of distribution of impurities from the position of the source and allowed to give a preliminary quantitative assessment.Представлена трёхмерная математическая модель распространения загрязнений в реках, протекающих в условиях криолитозоны, с учётом возможных деформаций русел, вызванных таянием слагающих их многолетнемёрзлых пород при повышении температуры воды речного потока. Рассматривается также распространение загрязняющих веществ, освобождаемых при размыве береговых склонов, обусловленном термоэрозией. Математическая модель состоит из четырёх блоков: гидродинамического, термического, деформационного и распространения примеси. Сравниваются результаты численного моделирования с данными натурных наблюдений и лабораторных экспериментов. На основе численных экспериментов сделаны выводы о характере распространения загрязнений при нахождении их источника в тающих ледяных пластинах, расположенных в береговом откосе
Деградация оледенения Джунгарского (Жетысу) Алатау во второй половине ХХ в.
No full textThe features of spatial and temporal changes of glaciation in Djungarian Alatau for 44 years (1956–2000) are discussed in the paper. The evaluation of the glacier evolution based on the comparison of their morphometric characteristics, obtained by cataloging in 1956, 1990 and 2000. The aerial photographs are used for the first two periods, and Landsat satellite imageries with resolution of 15 m – for 2000. In addition the maps of glaciation in scale 1:25 000 were used for 1990 and 2000. The result of this work showed that during 44 years 341 glaciers melted, 227 glaciers dissolved, and their total number decreased from 1412 to 1298. The area of glaciers reduced from 841 to 528 km² (37.2%, to 0.85 %/year). The altitude of the firn line lifted by 65 m, from 3550 m up to 3615 m. Total ice volume diminished from 39.3 down to 20.2 km³ (39.2%, to 0.89 %/year). The average value of the glacier mass balance now equals –37,6 g/cm². The total area of glaciers in the region in 2010 is estimated at 465 km². According to the author’s forecast, glaciers in Djungarian Alatau may disappear to 2090.Рассматриваются пространственно-временные изменения оледенения Джунгарского (Жетысу) Алатау за 44 года (1956–2000 гг.). Основой для суждения о направленности эволюции ледников послужило сравнение их морфометрических характеристик, полученных при каталогизации в 1956, 1990 и 2000 гг. Установлено, что за 44 года площадь оледенения сократилась на 313 км2 (37,2%). Объём ледников стал меньше на 13,1 км3 (39,2%). Среднее значение баланса массы оледенения составило −37,6 г/см2. Безвозвратная потеря массы со всей площади ледников равна 17 м в слое воды. В 2010 г. площадь оледенения в регионе оценивалась в 465 км2. По прогнозу, основанному на экстраполяции выявленных тенденций сокращения площади, ледники Джунгарского Алатау могут исчезнуть через 80 лет, т.е. к 2090 г