A package of momentum and heat transfer coefficientsfor the stable atmospheric surface layer

The polar atmospheric surface layer is often stably stratified, which strongly influences turbulent transport processes between the atmosphere and sea ice/ocean. Transport is usually parametrized applying Monin Obukhov Similarity Theory (MOST) which delivers transfer coefficients as a function of stability parameters (see below). In a series of papers (Gryanik and Lüpkes, 2018; Gryanik et al., 2020,2021; Gryanik and Lüpkes, 2022) it has been shown that differences between existing parametrizations are large, especially for strong stability. One reason is that they are based on different data sets, for which the origin of differences is still unclear. In this situation Gryanik et al. (2021) as well as Gryanik and Lüpkes (2022) proposed a numerically efficient method, which can be used for most of the existing data sets and their specific stability dependences. A package of parametrization resulted that is suitable for its application in weather prediction and climate models. Especially, calculation of fluxes over sea ice were improved. Combined with latest parametrizations of surface roughness it has a large impact on large scale fields as shown recently by Schneider et al. (2021) who applied some members of the package

Results of instrumental aerial survey of ice-associated seals on the ice in the Okhotsk Sea in May 2013

Populations of ice-associated seals in the Okhotsk Sea are assessed using modern instrumental aerial technique. The aerial survey was conducted over a part of the ice-covered area of the Sea on May 1-9, 2013 by means of thermal scan and visual digital photography from the aircraft-laboratory An-38 «Vostok». The ice covered area of the Okhotsk Sea in the time of survey was estimated as 242,000 km2, and 2,993 km2 of it was covered by survey transects with total length 5,617 km. The number of animals on all transects within the equipment swath was counted. Four seal species were identified: bearded, spotted, ribbon, and ringed seals, and their number and distribution were determined. The infra-red scanner recorded 5,730 seals on the ice and 4,360 these animals were photographed including 844 ringed seals, 453 bearded, 721 spotted, 1,805 ribbon, 435 pups non-identified to the species, and 102 non-identified to species adult seals. These assessments were extrapolated over the whole ice-covered area of the Okhotsk Sea using a linear model framework, and the following estimations of the species total abundance were presented (95 % confidence intervals in brackets): 88,253 (64,120-130,320) ringed seals, 39,743 (27,868-60,026) bearded seals, 181,179 (118,392-316,995) ribbon seals, and 84,356 (55,172-113,540) spotted seals. A database on all recorded seals with their «portrait-photos» and accompanying information is created on materials of the aerial survey. The developed instrumental technology can be used as a basis for wider aerial surveys of ice-associated seals in the North Pacific

Ignition of premixed air/fuel mixtures by microwave steamer discharge

A variety of methods exists for fast and efficient combustion of air-fuel mixtures. In this study, a microwave subcritical streamer discharge is used to ignite propane-air mixtures at atmospheric pressure. The streamer is initiated at the inner surface of a dielectric tube with the help of a passive half-wave vibrator. By creating a network of ignition lines, the streamer discharge forms the network of burning channels with large total surface area. This leads to the apparent speed of combustion propagation along the cylinder in excess of 100 m/s, which is more than 200 times the laminar flame propagation speed. The axial propagation of the combustion front in a cylindrical tube filled with the air/propane mixture is investigated by high speed video recording in visible light. A simple model is presented to explain observed results

Methodology for Development of a 600-Year Tree-Ring Multi-Element Record for Larch from the Taymir Peninsula, Russia

We developed a long (600-year) dataset for the concentrations of 26 elements in tree rings of larch from the Taymir Peninsula, the northernmost region in the world (ca. 72°N) where trees grow. Tree rings corresponding to the time period from 1300 to 1900 A.D. were studied. Eleven wood strips, each from a different larch tree, were cut into ca. 100 mg samples usually consisting of ten consecutive tree rings (but occasionally five). Between 19 and 40 consecutive samples resulted from each tree, yielding a total of 277 samples. The replication of each time interval ranged from three (for periods 1300-1400 A.D. and 1600-1700 A.D.) to six (for 1450-1600 A.D.). Wood samples were digested with concentrated HNO 3 for measurement of Li, B, Na, Mg, Al, Si, P, Cl, K, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Rb, Sr, Y, Zr, Nb, Mo, Ag, Cd, Sn, Sb, I, Ba, La, Ce, Nd, W, Au, Pb, Bi, Th, and U using solution Inductively Coupled Plasma Mass Spectrometry (ICPMS). Fourteen elements (V, Co, As, Y, Nb, Mo, Sb, La, Ce, Nd, W, Au, Th, and U) with extremely low concentrations were eliminated from consideration as unreliable. Here we report our sample preparation and measurement procedure, as well as the observed concentrations in tree rings, emphasizing considerations for developing representative and reliable denrodochemical datasets.Нами был получен длительный массив данных (600 лет) концентраций 26 элементов в годичных кольцах лиственницы с полуострова Таймыр, самого северного региона в мире (около 72° с.ш.), где возможен рост деревьев. Изучались годичные кольца, соответствующие промежутку времени с 1300 по 1900 год н.э. Одиннадцать древесных выпилов, по одному для каждой лиственницы, нарезались на образцы массой около 100 мг, которые, как правило, состояли из десяти годичных колец (но в некоторых случаях из пяти). Из каждого дерева было получено от 19 до 40 последовательных образцов, что дало в общей сложности 277 образцов. Повторность для каждого временного интервала варьировала от трех (для периодов 1300-1400 г.н.э. и 1600-1700 г.н.э.) до шести (для периода 1450-1600 г.н.э.). Древесные образцы растворяли в концентрированной HNO 3 для последующего измерения Li, B, Na, Mg, Al, Si, P, Cl, K, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Rb, Sr, Y, Zr, Nb, Mo, Ag, Cd, Sn, Sb, I, Ba, La, Ce, Nd, W, Au, Pb, Bi, Th и U при помощи масс-спектрометрии с индуктивно связанной плазмой (ICP-MS) для растворов. Четырнадцать элементов (V, Co, As, Y, Nb, Mo, Sb, La, Ce, Nd, W, Au, Th и U) с очень низкими концентрациями были исключены из рассмотрения как недостоверные. В данной статье, основной целью которой являлась отработка методики получения репрезентативных и достоверных дендрохимических данных, приводится использованная нами процедура пробоподготовки и измерений, а также полученные концентрации в годичных кольцах

Влияние неинвазивных методик респираторной поддержки на частоту летального исхода у взрослых пациентов с тяжелой дыхательной недостаточностью, вызванной новой коронавирусной инфекцией

The objective: to evaluate the effect of high-flow oxygen and non-invasive ventilation on the mortality rate in adults with severe respiratory failure caused by the new coronavirus infection in the intensive care unit (ICU).Subjects and methods. A one-center retrospective study was conducted. Electronic medical files of patients treated in the ICU from April 1 to May 25, 2020, were analyzed. Totally, 101 medical files were selected, further, they were divided into two groups. Group 1 (n = 49) included patients who received oxygen insufflation, and should it fail, they received traditional artificial ventilation. No non-invasive respiratory therapy was used in this group. Group 2 (n = 52) included patients who received high-flow oxygen therapy and non-invasive ventilation. The mortality rate in the groups made a primary endpoint for assessing the impact of high-flow oxygen therapy and non-invasive ventilation. The following parameters were also analyzed: drug therapy, the number of patients in whom non-invasive techniques were used taking into account the frequency of cases when these techniques failed, and the number of patients in whom artificial ventilation was initiated.Results. In Group 2, non-invasive methods of respiratory therapy were used in 31 (60%) cases. High-flow oxygen therapy was used in 19 (36%) of them; in 13 cases this method allowed weaning them from the high flow. Non-invasive ventilation was used in 18 cases, in 12 patients it was used due to progressing severe respiratory failure during humidified oxygen insufflation, in 6 patients – after the failed high-flow oxygen therapy. In Group 1, 25 (51%) patients were intubated and transferred to artificial ventilation, in Group 2, 10 (19.2%) underwent the same. The lethal outcome was registered in 23 (47%) cases in Group 1, and in 10 (19.2%) in Group 2 (p = 0.004). Analysis of drug therapy in the groups revealed the difference in the prescription of pathogenetic therapy. Logistic regression demonstrated the effectiveness of the combination of tocilizumab + a glucocorticoid in reducing the frequency of lethal cases (p = 0.001).Conclusion. The use of non-invasive respiratory support in adults with severe respiratory failure caused by the new coronavirus infection combined with therapy by tocilizumab + a glucocorticoid can reduce the incidence of lethal cases.Цель исследования: оценить влияние высокопоточной оксигенотерапии и неинвазивной вентиляции легких на частоту летального исхода у взрослых пациентов с тяжелой дыхательной недостаточностью, вызванной новой коронавирусной инфекцией, в отделении реанимации и интенсивной терапии (ОРИТ).Материалы и методы. Проведено одноцентровое ретроспективное исследование. Проанализированы электронные медицинские карты пациентов, находившихся на лечении в ОРИТ с 1 апреля по 25 мая 2020 г. Общее количество отобранных медицинских карт составляло 101, далее они были разделены на две группы. В группу № 1 (n = 49) включены пациенты, которым проводили инсуффляцию кислорода, а в случае неэффективности ‒ традиционную искусственную вентиляцию легких. В данной группе не применяли неинвазивные методики респираторной терапии. Группу № 2 (n = 52) составили пациенты, у которых использовали высокопоточную оксигенотерапию и неинвазивную вентиляцию легких. Первичной конечной точкой оценки влияния высокопоточной оксигенотерапии и неинвазивной вентиляции легких считали частоту летального исхода в исследуемых группах. Анализировали также медикаментозную терапию, количество пациентов, у которых применяли неинвазивные методики, учитывали частоту их неэффективного использования, число пациентов, которым инициировали искусственную вентиляцию легких.Результаты. Неинвазивные методики респираторной терапии в группе № 2 использованы в 31 (60%) случае. Высокопоточную оксигенотерапию применяли у 19 (36%) пациентов из них; в 13 случаях использование данного метода позволило отлучить от высокого потока. Неинвазивная вентиляция легких применена в 18 случаях, у 12 пациентов ее использовали при нарастании клиники тяжелой дыхательной недостаточности на фоне инсуффляции увлажненного кислорода, у 6 пациентов ‒ после неэффективности высокопоточной оксигенотерапии. Интубация трахеи и перевод на искусственную вентиляцию легких выполнены у 25 (51%) пациентов группы № 1, 10 (19,2%) пациентов группы № 2. Летальный исход в группе № 1 зарегистрирован в 23 (47%) случаях, в группе № 2 ‒ в 10 (19,2%) (p = 0,004). Анализ медикаментозной терапии в исследуемых группах показал различие в назначении патогенетической терапии. Логистическая регрессия продемонстрировала эффективность использования комбинации тоцилизумаб + глюкокортикоид в снижении частоты летального исхода (p = 0,001).Вывод. Использование неинвазивных методик респираторной поддержки у взрослых пациентов с тяжелой дыхательной недостаточностью, вызванной новой коронавирусной инфекцией, в сочетании с терапией в комбинации тоцилизумаб + глюкокортикоид позволяет снизить частоту развития летального исхода

New modified and extended stability functions for the stable boundary layer based on SHEBA data

The calculation of the near-surface turbulent fluxes of energy and momentum in climate and weather prediction models requires transfer coefficients. Currently used parametrizations of these coefficients are based on stability functions derived from measurements over land and not over sea ice. However, recently, a non-iterative parametrization has been proposed by Gryanik and Lüpkes (2018), which can be applied to climate and weather prediction models as well but uses stability functions of Grachev et al. (2007). These functions had been obtained from measurements during the Surface Heat Budget over the Arctic Ocean campaign (SHEBA) and thus from measurements over sea ice. A drawback of the scheme of Gryanik and Lüpkes (2018) is that there is still some complexity due to the complexity of the SHEBA based functions. Thus new stability functions are proposed for the stable boundary layer, which are also based on the SHEBA measurements but avoid the complexity. It is shown that the new functions are superior to the former ones with respect to the representation of the measured relationship between the Obukhov length and the bulk Richardson number. Moreover, the resulting transfer coefficients agree slightly better with the SHEBA observations in the very stable range. Nevertheless, the functions fulfill the same criteria of applicability as the earlier functions and contain furthermore as an extension a dependence on the neutral Prandtl number. Applying the new functions, an efficient non-iterative parametrization of the near-surface turbulent fluxes of momentum and heat is developed where transfer coefficients result as a function of the bulk Richardson number (Rib) and roughness parameters. The new transfer coefficients, which are recommended for weather and climate models, agree well with the SHEBA data in a large range of stability (0< Rib<0.5) and with those based on the Dyer-Businger functions in the range Rib <0.08