Characteristics of atmosphere - sea ice energy exchange in the Central Arctic

Analysis of an interaction between long-term ice cover and atmosphere in different regions of the Arctic Ocean is conducted. For comparison the energy exchange characteristics in the western and eastern periphery of the Beaufort Gyre, the central part of the Arctic Ocean and in the area to the north of the Kara and Barents seas have been analyzed. The results of calculations based on special observations at Russian drifting station "North Pole-4" and its interpretation using a simple thermodynamic model of sea ice were used. As modern in situ data, meteorological observations at drifting stations "North Pole-35" (2007-2008) and "North Pole-39" (2011-2012) were used. Calculations of turbulent heat fluxes in the region of the drift of the American station "SHEBA" were performed. A good agreement between the calculated fluxes based on the historical data and NP-39 data for the summer period is shown. Monthly mean values and standard deviations of meteorological parameters for winter period are presented on the basis of data from drifting stations "North Pole-35" – "North Pole-40" (2007-2013)

Meteorological winter conditions in the Central Arctic according to the drifting stations “North Pole 35-40”

The effect of clouds, wind speed and long-wave radiative balance on the surface and near-surface air temperature in the Arctic during polar night is presented. The most pronounced bimodality in frequency distributions of the cloud fraction corresponding to cloudy and clear-sky situations is found for the stations NP-35 (2007-2008), NP-37 (2009-2010) and NP-38 (2010-2011). A strong impact of the presence or absence of clouds on the air-surface temperature difference is shown. For clear-sky situations nonmonotonic dependency of near-surface air temperature on wind speed is found

Многолетняя изменчивость характеристик климата Северной Якутии — экстремумы температуры воздуха

The article continues the series of publications, describing the modern climate of atmospheric surface layer in the Northern Yakutia and, in details, in the area of Tiksi Hydrometeorological observatory. Climatic characteristics of minimal and maximal air temperatures are estimated with data of standard meteorological measurements, executed at 22 marine and continental meteorological stations in 1978–2010 years, and at HMO Tiksi — during 1936–2015 years. These estimates supplement the information of climatic reference books, based on the data executed before 1980 year, and for some meteorological stations — before 1965 year. The basic characteristics of extremes by months, maps of its spatial distribution and conjugation, annual extremes (the largest and smallest values, its distributions by months, and trends), climatic parameters of seasonal amplitude, and estimates of extreme temperatures, possible one time during 5, 10, 50 and 100 years periods are presented. In addition, the synoptic conditions of storms and sharp temperature changes are investigated.Статья продолжает цикл работ по описанию современного климата приземной атмосферы Cеверной Якутии и, более подробно, района Гидрометеорологической обсерватории Тикси. Климатические характеристики минимальной и максимальной температуры воздуха получены по данным стандартных метеорологических измерений с 1978 по 2010 г. на 22 морских и континентальных ГМС, а для ГМО Тикси — по всем доступным данным c 1936 по 2015 г. Приведенные оценки дополняют информацию климатических справочников, основанную на данных, полученных до 1980 г., а на ряде ГМС и до 1965 г. Представлены таблицы основных характеристик экстремумов по месяцам, карты пространственного распределения и сопряженности, годовые экстремумы (наибольшие и наименьшие значения, их распределение по месяцам и тренды), климатические параметры амплитуды годового хода, оценки экстремальных значений температуры, возможных один раз в 5, 10, 25, 50 и 100 лет. Дополнительно исследованы синоптические условия возникновения штормов и резких перепадов температуры

Growth of the fast ice and its influence on the freezing of bottom sediments in the Buor-Khaya Bay coastal zone, Laptev Sea (in Russian)

Results of the ice and hydrological measurements carried out in the winter of 2014/15 in theTiksiGulf(Buor-KhayaBay) are described. These data served a basis for development of a conceptual thermodynamic model of seasonal freezing of the sea water layers and underlying bottom sediments in the sea-shore zone. The model uses two methods of localization of the phase transition zones: a classical (frontal) one is used for water, while another one within the range of temperatures – for the bottom. For real atmospheric conditions, we investigated specific features of the water freezing through in the shallow coastal zone of theLaptev Sea. The quantitative characteristics of the process were obtained. The calculations demonstrated that the distinguishing feature of the process is a stabilization of the ice thickness, taking place due to essential increasing of a salinity of the sea water. As a result of this, a shallow water body does not frozen through down to the bottom at even the very low air temperatures. Cooled salt waters does not allow liquid to be frozen in pores of the bottom ground. Salinization of the under-ice water layer can cause the melting of fast ice in the shallow water with its simultaneous increase away from the coast. Ice formation in water layers and bottom sediments begins at the same time, although it proceeds differently at different depths. Due to salinization of the bottom ground a continuous frozen zone is not formed, and the whole layer of freezing precipitation is a two-phase (partially frozen) area. As a whole, the model estimates of the process parameters including the motions of the phase fronts agree with known data of direct measurements. Despite such conformity, the model data should be considered as only evaluative ones. If a bottom is flat, the horizontal mixing and advection, which are not reproduced by a one-dimensional model in principle, the actual salinity parameters will most likely not reach the calculated values. However, for small values of the tides in theBuor-KhayaBayand insignificant reverse flows of salt, effect of the last ones does not apparently exert significant influence on the intensity of cooling of the under-ice water layer as well as on the ice formation in upper layers of the bottom within such time scales as a season

Припайный лёд в прибрежной части пролива Шокальского

Field investigations of coastal fast ice near the research station Ice Base on the «Cape Baranova», carried out in 2013–2014, made possible to reveal a number of characteristics of the sea ice cover formation. It has been shown that during winter and early spring the sea ice thickness, being formed due to intensive snow drift and caused by that flooding of the ice cover just near the coast of the Bolshevik Island, substantially grows at its upper boundary, that is typical for the Antarctic seas. At the same time, similar process of the ice growth at a relatively short distance from the coast shows all features characteristic for the ice cover in the Arctic seas, and that is well reproduced by the conceptual numerical sea ice model. Thus, the region of the Ice Base «Cape Baranova» represents a natural laboratory for studying the processes of the sea ice formation in both, the Arctic and Antarctic seas under condition of the same atmospheric forcing. Transformation of the fast ice structure during the summer time is described. Results of the investigations has demonstrated that despite the radical changes in the structure thicknesses of the fast ice remained almost unchanged due to the ice growth on the bottom boundary of the ice cover until a destruction of it in August.Приведены результаты исследований припайных льдов пролива Шокальского в районе научно‑исследовательского стационара «Ледовая база «Мыс Баранова». Установлена роль снежного покрова в процессах формирования ледяного покрова в зимний период, характерных как для арктических, так и антарктических морей. Описана трансформация структуры льда в летний период. Показано, что, несмотря на радикальное изменение структуры, толщина припайных льдов практически не изменяется вплоть до взлома припая в августе в результате нарастания льда на нижней границе ледяного покрова

Динамика сезонного протаивания мерзлоты в районе научно-исследовательского стационара «Ледовая база “Мыс Баранова”» (о. Большевик, арх. Северная Земля)

The results of permafrost observations in the northern part of theBolshevikIsland(Severnaya Zemlya Archipelago) started in February 2016 at the meteorological site of the research station “Ice Base “CapeBaranov” are presented. Features of two-year measurements of temperature, heat flux and humidity in the soil active layer due to the processes of its seasonal thawing/freezing, including the so-called “zero curtain effect” are described. The review of climatic and landscape characteristics of the research area, as well as the parameterization of thermophysical properties of the three main types of arctic soils (sandy, sandy loamy and clayey) in the frozen and thawed state was performed. Using the stationary model, realizing the Kudryavtsev’s algorithm, the data of atmospheric reanalysis and direct meteorological observations, interannual variability of seasonal thawing depth as well as mean annual temperature of permafrost surface for various soil types on theBolshevikIslandwere obtained. It is shown that the permafrost-climatic changes during last 70 years, despite significant interannual fluctuations, reflecting the variability of atmospheric conditions at the Severnaya Zemlya Archipelago, are consistent with global temperature increase, and taken into account variations in the snow layer thicknesses and vegetation cover are close to the same measured in 2016–2017 years.Представлены результаты первых мерзлотных наблюдений в северной части о. Большевик (арх. Северная Земля), начатых в феврале2016 г. на НИС «Ледовая база “Мыс Баранова”». Описаны особенности температурной структуры и влажности деятельного слоя грунта, обусловленные процессами сезонного протаивания/промерзания, включая так называемый «эффект нулевого занавеса». Выполнена параметризация теплофизических свойств основных типов арктических грунтов в мерзлом и талом состоянии. С помощью стационарной модели, основанной на известном алгоритме Кудрявцева, данных атмосферного реанализа и прямых метеонаблюдений получены оценки многолетней изменчивости глубины сезонного протаивания грунтов о. Большевик. Показано, что мерзлотно-климатические изменения последних 70 лет, несмотря на существенные межгодовые колебания, согласуются с ходом глобального повышения температуры

РОСТ ПРИПАЯ И ЕГО ВЛИЯНИЕ НА ЗАМЕРЗАНИЕ ВЕРХНЕГО СЛОЯ ДОННЫХ ОТЛОЖЕНИЙ В ПРИБРЕЖНОЙ ЗОНЕ ГУБЫ БУОР-ХАЯ (МОРЕ ЛАПТЕВЫХ)

Results of the ice and hydrological measurements carried out in the winter of 2014/15 in theTiksiGulf(Buor-KhayaBay) are described. These data served a basis for development of a conceptual thermodynamic model of seasonal freezing of the sea water layers and underlying bottom sediments in the sea-shore zone. The model uses two methods of localization of the phase transition zones: a classical (frontal) one is used for water, while another one within the range of temperatures – for the bottom. For real atmospheric conditions, we investigated specific features of the water freezing through in the shallow coastal zone of theLaptev Sea. The quantitative characteristics of the process were obtained. The calculations demonstrated that the distinguishing feature of the process is a stabilization of the ice thickness, taking place due to essential increasing of a salinity of the sea water. As a result of this, a shallow water body does not frozen through down to the bottom at even the very low air temperatures. Cooled salt waters does not allow liquid to be frozen in pores of the bottom ground. Salinization of the under-ice water layer can cause the melting of fast ice in the shallow water with its simultaneous increase away from the coast. Ice formation in water layers and bottom sediments begins at the same time, although it proceeds differently at different depths. Due to salinization of the bottom ground a continuous frozen zone is not formed, and the whole layer of freezing precipitation is a two-phase (partially frozen) area. As a whole, the model estimates of the process parameters including the motions of the phase fronts agree with known data of direct measurements. Despite such conformity, the model data should be considered as only evaluative ones. If a bottom is flat, the horizontal mixing and advection, which are not reproduced by a one-dimensional model in principle, the actual salinity parameters will most likely not reach the calculated values. However, for small values of the tides in theBuor-KhayaBayand insignificant reverse flows of salt, effect of the last ones does not apparently exert significant influence on the intensity of cooling of the under-ice water layer as well as on the ice formation in upper layers of the bottom within such time scales as a season.Представлены и проанализированы данные стандартных ледовых наблюдений зимой 2014/15 г. в бухте Тикси (губа Буор-Хая, южная часть моря Лаптевых). Описаны особенности изменчивости поля температур в припайном льду и подлёдном слое моря. Данные наблюдений дополнены модельными оценками замерзания слоя воды и верхних слоёв донных отложений

Аэрозольная составляющая приводного слоя атмосферы по данным наблюдений экспедиции «Север-2015»

The results of the atmospheric sea surface layer aerosol composition studies executed during expedition “Sever-2015” on the route from Arkhangelsk to the Severnaya Zemlya archipelago from October 9 to 26, 2015 are presented. The data about mass concentration of black carbon (EBC) obtained with high spatial-temporal resolution in the White, Barents and Kara Seas showed its signifi cant variability: from background values about 20 ng/m3 to values of more than 1000 ng/m3 during periods of air mass transfer from the continent. Cluster analysis of the microstructure of natural arctic aerosols gave possibility to identify the dominant groups of particles of sea salt and calcium sulfate. In case the increase of EBC up to 250 ng/m3 the groups of carbon-containing aerosols and particles rich in sulfur, characteristic for emissions from the combustion of natural fuel were revealed.Приведены результаты исследований аэрозольного состава приводного слоя атмосферы, выполненных в ходе экспедиции «Север-2015» на маршруте от порта Архангельск до архипелага Северная Земля в период 9–26 октября 2015 г. Полученные с высоким пространственно-временным разрешением данные о массовой концентрации черного углерода (EBC) на акваториях Белого, Баренцева и Карского морей показали ее значительную изменчивость: от фоновых значений порядка 20 нг/м3 до значений более 1000 нг/м3 в периоды переноса воздушных масс с континента. Кластерный анализ микроструктуры природных арктических аэрозолей позволил выделить доминирующие группы частиц морской соли и сульфатов кальция. При увеличении EBC до 250 нг/м3 обнаружено появление групп углеродосодержащих аэрозолей и частиц, богатых серой, характерных для эмиссий при сжигании природных топлив

Трансарктика-2019: зимняя экспедиция в Северный Ледовитый океан на НЭС «Академик Трёшников»

Preliminary results of the Transarktika-2019 winter expedition in the Arctic Ocean on the R/V “Akademik Tryoshnikov” are presented. The expedition program included studies on meteorology, hydrology, hydrochemistry, hydrobiology, geology, geophysics and an extensive complex of ice measurements in the Northern Barents Sea from the drifting ice and from the ship. During the expedition, it was possible to complete a wide range of tasks. The data obtained comprise a unique material for a comprehensive study of the current state of the environmental conditions in the Barents Sea. This paper highlights the most significant preliminary results of multidisciplinary observations in various environments, which will be further comprehensively analyzed and published in separate thematic articles.Представлены предварительные результаты зимней экспедиции «Трансарктика-2019» в Северном Ледовитом океане на НЭС «Академик Трёшников». Программа экспедиции включала в себя исследования по метеорологии, гидрологии, гидрохимии, гидробиологии, геологии, геофизике и обширному комплексу измерений ледяного покрова в северной части Баренцева моря с дрейфующего льда и с борта судна. Во время экспедиции удалось выполнить широкий круг задач. Полученные данные представляют собой уникальный материал для всестороннего изучения текущего состояния условий окружающей среды в Баренцевом море. В статье обозначены наиболее значимые предварительные результаты междисциплинарных наблюдений в различных средах, которые в дальнейшем будут всесторонне проанализированы и опубликованы в отдельных тематических статьях

Опыт дистанционного температурно-влажностного зондирования атмосферы в период дрейфа НЭС «Академик Трешников»

For the first time experience was gained with the operation of Russian equipment for water content and temperature remote sensing of the lower atmosphere in the Arctic. The comparison the results of measurements by radiometric systems with data of radiosoundings in wide range of meteorological conditions had been executed. It is shown that mean difference between integral atmospheric water content, measured by water vapor radiometer WVR, and calculated from radiosoundings data does not exceed 6 % with standard deviation 0.54 kg/m2 and significant correlation coefficient 0,92. Analysis the data of meteorological temperature profiler MTR-5 allows to conclude that in general its adequately reproduce air temperature profiles in the atmospheric lower 1000 m layer. Some deviations take place only in cases of large temperature gradients. Preliminary analysis of WVR data showed that monthly mean value of integral atmospheric water content in area under study in April 2019 year practically coincides with calculated from radiosoundings, performed in 1983—1988 years at the polar station Barentsburg, nearest to the drift region, 3.61 and 3.62 kg/m2 respectively. Same time hourly mean values of integral atmospheric water content during drift varied from 2 to 10 kg/m2, with extreme values recorded between April 15 and April 20, probably due to intensive transport of air masses of the Atlantic origin. Based on MTR-5 data it was concluded that despite differences in sounding technology, the place and time of observations, the statistics of inversions registered during drift correspond well to statistics of inversions, recorded on the Arctic coastal stations and over sea ice cover of the Weddell Sea in winter.Приведено описание работы комплекса аппаратуры влажностно-температурного дистанционного зондирования нижнего слоя атмосферы (радиометр РВП и метеорологический профилемер МТР-5РЕ) в условиях Арктики. Выполнено сравнение результатов измерений радиометрических систем с данными аэрологического зондирования в широком спектре метеорологических условий. Получены оценки интегрального влагосодержания атмосферы и характеристик инверсий в нижнем 1000-метровом слое атмосферы в период дрейфа НЭС «Академик Трёшников» в северной части Баренцева моря