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2021 ◽  
Author(s):  
Michael Warscher ◽  
Thomas Marke ◽  
Ulrich Strasser

Abstract. According to the living data process in ESSD, this publication presents extensions of a comprehensive hydrometeorological and glaciological data set for several research sites in the Rofental (1891–3772 m a.s.l., Ötztal Alps, Austria). Whereas the original dataset has been published in a first original version in 2018 (https://doi.org/10.5194/essd-10-151-2018), the new time series presented here originate from meteorological and snow-hydrological recordings that have been collected from 2017 to 2020. Some data sets represent continuations of time series at existing locations, others come from new installations complementing the scientific monitoring infrastructure in the research catchment. Main extensions are a fully equipped automatic weather and snow monitoring station, as well as extensive additional installations to enable continuous observation of snow cover properties. Installed at three high Alpine locations in the catchment, these include automatic measurements of snow depth, snow water equivalent, volumetric solid and liquid water content, snow density, layered snow temperature profiles, and snow surface temperature. One station is extended by a particular arrangement of two snow depth and water equivalent recording devices to observe and quantify wind-driven snow redistribution. They are installed at nearby wind-exposed and sheltered locations and are complemented by an acoustic-based snow drift sensor. The data sets represent a unique time series of high-altitude mountain snow and meteorology observations. We present three years of data for temperature, precipitation, humidity, wind speed, and radiation fluxes from three meteorological stations. The continuous snow measurements are explored by combined analyses of meteorological and snow data to show typical seasonal snow cover characteristics. The potential of the snow drift observations are demonstrated with examples of measured wind speeds, snow drift rates and redistributed snow amounts in December 2019 when a tragic avalanche accident occurred in the vicinity of the station. All new data sets are provided to the scientific community according to the Creative Commons Attribution License by means of the PANGAEA repository (https://www.pangaea.de/?q=%40ref104365).


2021 ◽  
Author(s):  
Don Perovich ◽  
Ian Raphael ◽  
Ryleigh Moore ◽  
David Clemens-Sewall

<p>Four seasonal ice mass balance buoys were deployed as part of the MOSAiC distributed network. These instruments measured vertical profiles of snow and ice temperature, as well as snow depth and ice thickness every six hours. Ice growth, surface melt, and bottom melt, as well as temporally averaged estimates of ocean heat fluxes, were calculated from these measurements. The buoys were installed in October 2019, with durations ranging from February 2020 to July 2020. Three of the buoys were destroyed in ridging events in February, March, and June 2020. The fourth buoy lasted until floe breakup in July 2020. The sites were separated by tens of kilometers, but had very similar air temperatures. While air temperatures were similar, snow – ice interface temperatures at different buoys varied by as much as 15 C due to differences in snow depth and ice thickness. Initial ice thicknesses ranged from 0.30 to 1.36 meters. During the growth season snow depths typically were around 0.1 to 0.2 meters, except for one case where the buoy was in a snow drift and the snow depth exceeded 0.5 meter. Peak growth rates of about 0.8 cm per day occurred in January. In mid-January there was a rapid increase in ice thickness associated with an aggregation of platelet ice. This aggregation only lasted for two weeks. In mid-April, air temperatures increased to nearly 0 C, almost ending the growth season.</p>


2021 ◽  
Author(s):  
Michael Warscher ◽  
Florian Hanzer ◽  
Carsten Becker ◽  
Ulrich Strasser

<p>The Rofental is a high Alpine environmental research basin in the Ötztal Alps (Austria, 1890 - 3770 m a.s.l.). The existing measurement network has recently been extended by new stations and sensors that focus on automated recordings of snow cover properties. Core of the network are three automatic weather stations (AWS) that incorporate 10 min. recordings of snow depth (SD), snow water equivalent (SWE), layered snow temperatures, snow surface temperature, snow density, as well as solid and liquid water content of the snowpack. One AWS is extended by a particular setup of two SD and SWE measurements at nearby wind-exposed and sheltered locations, complemented by an acoustic-based snow drift sensor to quantify wind-driven snow redistribution.</p><p>We here present analyses of the publicly available data that focus on snow drift events in an avalanche-prone winter season. The two nearby SWE measurements show differences of around 500% of measured peak SWE at a horizontal distance of only 25 m caused by wind-driven redistribution. In addition, the presented data is used to develop and validate the new open source, distributed snow cover model openAMUNDSEN. We evaluate different integrated energy balance and snow layer schemes and compare the data to results of the ESM-SnowMIP project.</p>


2021 ◽  
Author(s):  
Mohammad Salahshour

In many biological populations, individuals face a complex strategic setting, where they need to make strategic decisions over a diverse set of issues. To study evolution in such a complex strategic context, here we introduce evolutionary models where individuals play two games with different structures. Individuals decide upon their strategy in a second game based on their knowledge of their opponent's strategy in the first game. By considering a case where the first game is a social dilemma, we show that, as long as the second game has an asymmetric Nash equilibrium, the system possesses a spontaneous symmetry-breaking phase transition above which the symmetry between cooperation and defection breaks. A set of cooperation supporting moral norms emerges according to which cooperation stands out as a valuable trait. Notably, the moral system also brings a more efficient allocation of resources in the second game. This observation suggests a moral system has two different roles: Promotion of cooperation, which is against individuals' self-interest but beneficial for the population, and promotion of organization and order, which is at both the population's and the individual's self-interest. Interestingly, the latter acts like a Trojan horse: Once established out of individuals' self-interest, it brings the former with itself. Furthermore, we show that in structured populations, recognition noise can have a surprisingly positive effect on the evolution of moral norms and facilitates cooperation in the Snow Drift game.


2020 ◽  
Vol 80 (4) ◽  
pp. 36-41
Author(s):  
G. Tulekova ◽  
S. Kudaibergenov ◽  
◽  

There are many examples of crises and catastrophes in the history of mankind. Almost the entire spectrum of natural disasters is possible in Kazakhstan. In particular, earthquakes, floods, fires in forests and steppes, snowstorms, and others. In all mountain and foothill zones, there is a danger of landslides, the threat of snow drift. In addition, there are situations that have arisen for man-made reasons. These catastrophes are the result of human activity. Such extreme situations require the concentration of all physical and psychological capabilities of a person. This is especially important for military personnel who often operate in extreme or critical conditions. Psychological readiness to solve such situations gives the individual confidence in the correctness of their own actions and, in the end, leads to a successful result. The purpose of this article is to present the results of research in the framework of a master's thesis. The main focus is on the analysis of the features of psychological training of military personnel to act in an extreme situation. The studied problem is revealed by the authors from the point of view of modern approaches to the psychological training of military personnel in a critical situation. The research methods used (analysis, generalization, experiment) allowed us to reveal the depth of the problem relevant to military psychology. The research is based on the results of modern research by Kazakh and foreign scientists. Approaches to the interpretation of the essence of the content of the concept "extreme situation" are considered, and the factors that determine the specifics of psychological training of military personnel to act in a crisis are highlighted. The concept of "psychological readiness of military personnel to work in critical (extreme) situations" is defined. Statistical results of the experiment are presented. The experimental activity carried out in the course of experimental work has a high practical significance, since it was successfully tested through the implementation of the work of the military unit 3176 "K" in Pavlodar and can be used in the psychological training of military personnel. The article is devoted to the actual problem of psychology. The results presented in the article may be useful for military psychologists.


2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Xintong Jiang ◽  
Zhixiang Yin ◽  
Hanbo Cui

A long-span sports centre generally comprises multiple stadiums and gymnasiums, for which mutual interference effects of wind-induced snow motion are not explicitly included in the specifications of various countries. This problem is addressed herein by performing wind tunnel tests and numerical simulations to investigate the snow distribution and mutual interference effect on the roofs of long-span stadiums and gymnasiums. The wind tunnel tests were used to analyse the influences of the opening direction (0°, 90°, 180°, and 270°) and spacing (0.3 L, 0.5 L, 1 L, 1.5 L, 2 L, and 2.5 L, where L is the gymnasium span) of the stadium and gymnasium. The wind tunnel tests and numerical simulations were used to analyse the influence of the wind direction angle (from 0° to 315°, there are a total of eight groups in 45° intervals). The following results were obtained. The stadium opening had a significant effect on the snow distribution on the surface of the two structures. An even snow distribution was obtained when the stadium opened directly facing the gymnasium, which corresponded to the safest condition for the structures’ surfaces. As the spacing between the buildings increased, the interference effect between the two structures was reduced. The interference was negligible for a spacing of 2 L. The stadium had the most significant amplification interference effect on the gymnasium for a wind direction angle of 45°, which was extremely unfavourable to the safety of the structure. The most favourable wind direction angle was 270°, where there were both amplification interference and blockage interference.


2020 ◽  
Vol 20 (6) ◽  
pp. 1847-1865
Author(s):  
Anita Verpe Dyrrdal ◽  
Ketil Isaksen ◽  
Jens Kristian Steen Jacobsen ◽  
Irene Brox Nilsen

Abstract. A number of seaside communities in Troms, northern Norway, are vulnerable to sudden weather-induced access disruptions due to high-impact weather and dependency on one or few roads. In this paper we study changes in winter weather known to potentially cause access disruptions in Troms, for the present climate (1958–2017) and two future periods (2041–2070; 2071–2100). We focus on climate indices associated with snow avalanches and weather that may lead to for example slippery road conditions. In two focus areas, the most important results show larger snow amounts now compared to 50 years ago, and heavy snowfall has become more intense and frequent. This trend is expected to turn in the future, particularly at low elevations where snow cover during winter might become a rarity by 2100. Strong snow drift, due to a combination of snowfall and wind speed, has slightly increased in the two focus areas, but a strong decrease is expected in the future due to less snow. Events of heavy rain during winter are rather infrequent in the present winter climate of Troms, but we show that these events are likely to occur much more often in all regions in the future.


2020 ◽  
Author(s):  
Jean-Luc Velotiana Ralaiarisoa ◽  
Florence Naaim-Bouvet ◽  
Kenji Kosugi ◽  
Masaki Nemoto ◽  
Yoichi Ito ◽  
...  

<p>Aeolian transport of particles occurs in many geophysical contexts such as wind-blown sand or snow drift and is governed by a myriad of physical mechanisms. Most of drifting particle are transported within de saltation layer and has been largely studied for cohesionless particles whether for snow or for sand. Thus, the theoretical description of aeolian transport has been greatly improved for the last decades. In contrast cohesive particles-air system have received much less attention and there remain many important physical issues to be addressed.  </p><p>        In the present study, the characteristics of drifting cohesive snow phenomena is investigated experimentally Several wind tunnel experiments were carried out in the Cryopsheric Environment simulator at Shinjo (Sato et al., 2001). Spatial distribution of wind velocity and the mass flux of drifting snow were measured simultaneously by an ultrasonic anemometer and a snow particle counter. The SPC measures the size of each particle passing through a sampling area. The size is classified into 32 classes between 50 and 500µm. Compacted snow was sifted on the floor. Then snow bed is left for a determined duration time to become cohesive by sintering.Two kinds of snow beds with different compression hardness were used (“hard snow” with a compression hardness of about 60 kPa and “semi hard snow” with a compression hardness of about 30 kPa). Wind tunnel velocity varied from 7 m/s to 15 m/s. Moreover steady snow drifting can be produced by seeding snow particles at a constant rate at the upwind of the test section. The results are compared with those obtained for loose surfaces. It was shown that :</p><p>- on hard snow cover, aerodynamic entrainment does not occur and saltating particles from the seeder just rebounded without splashing particles composing the snow surface (Kosugi et al.,2004). b, the inverse of the gradient of the mass flux decay with height is proportional to the friction velocity. The mass flux profiles exhibit a focus point. It is also confirmed (Kosugi et al., 2008) that the saltation height increased with increasing particle diameter throughout the full range of investigated wind tunnel velocity. Such characteristics are not observed for cohesionless snow particles (Sugiura et al.,1998)</p><p>-on semi hard snow cover, the inter-particle cohesion makes the transport unsteady and spatially inhomogeneous. A steady state is never obtained. It makes experimental protocol and experiments repeatability tricky. Without seeder, the same trends are observed compared to the previous experiments on hard snow. With seeder, the drifting snow flux dramatically increases, even for low wind speed, leading to snow cover vanish.</p>


2020 ◽  
Vol 32 (1) ◽  
pp. 29-42
Author(s):  
Matti Leppäranta ◽  
Arto Luttinen ◽  
Lauri Arvola

AbstractShallow Antarctic surface lakes belong to the most extreme aquatic environments on the Earth. In Vestfjella, proglacial surface lakes and ponds are characterized by a 2–5 month long period with liquid water and depths < 2 m. We give a detailed description of nine seasonal lakes and ponds situating at three nunataqs (Basen, Plogen and Fossilryggen) in western Dronning Maud Land. Their physical and geochemical properties are provided based on observations in four summers. Three main ‘lake categories‘ were found: 1) supraglacial lakes, 2) epiglacial ponds and 3) nunataq ponds. Category 3 lakes can be divided into two subgroups with regards to whether the meltwater source is glacial or just seasonal snow patches. Supraglacial lakes are ultra-oligotrophic (electrical conductivity < 10 μS cm−1, pH < 7), while in epiglacial ponds the concentrations of dissolved and suspended matter and trophic status vary over a wide range (electrical conductivity 20–110 μS cm−1, pH 6–9). In nunataq ponds, the maxima were an electrical conductivity of 1042 μS cm−1 and a pH of 10.1, and water temperature may have wide diurnal and day-to-day fluctuations (maximum 9.3°C) because snowfall, snow drift and sublimation influence the net solar irradiance.


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