A Simple Snow-Cover Model for Avalanche Warning in Japan

One of the principal aims of avalanche warning is to prevent slab avalanches triggered by skiers. Other than explosives, the best practical tool for stability evaluation is the Rutschblock test. Whether the slab may be triggered by a skier depends on various slab characteristics. Important factors seem to be depth of the weak layer, slab hardness and sublayering of the slab. The stress distribution induced by a skier is calculated by the finite element method for typical snow-cover configurations. The additional shear stress is of the same order of magnitude as the shear strength of weak layers. Besides the critical weak layer — prerequisite for a slab avalanche — hard layers seem to be important. The analysis suggests that a shear failure is most probable at the transition from a hard to a soft layer. This corresponds well to observations of slab-avalanche profiles. The results may help to improve and quantify the analysis of snow profiles.

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Application of the snow cover model SNOWPACK to snow avalanche warning in Niseko, Japan

Cold Regions Science and Technology ◽

10.1016/j.coldregions.2005.05.007 ◽

2005 ◽

Vol 43 (1-2) ◽

pp. 62-70 ◽

Cited By ~ 14

Author(s):

Kouichi Nishimura ◽

Emiko Baba ◽

Hiroyuki Hirashima ◽

Michael Lehning

Keyword(s):

Snow Cover ◽

Snow Avalanche ◽

Avalanche Warning

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pSNOWPACK: a forecasting tool for avalanche warning services

The Cryosphere Discussions ◽

10.5194/tcd-5-2253-2011 ◽

2011 ◽

Vol 5 (4) ◽

pp. 2253-2278

Author(s):

S. Bellaire ◽

J. B. Jamieson ◽

C. Fierz

Keyword(s):

Snow Cover ◽

Model Comparison ◽

Weather Forecasting ◽

Meteorological Data ◽

Single Point ◽

Additional Information ◽

Stability Data ◽

Avalanche Warning ◽

Warning Services ◽

Model Chain

Abstract. Avalanche danger is often estimated based on snow cover stratigraphy and snow stability data. In Canada, single forecasting regions are very large (>50 000 km2) and snow cover data are often not available. To provide additional information on the snow cover and its seasonal evolution the Swiss snow cover model SNOWPACK was therefore coupled with a regional weather forecasting model GEM15. We assess the capability of this model chain (pSNOWPACK) to forecast three key factors of snow cover instability at a single point: new snow amounts, surface hoar formation and crust formation. The output of GEM15 was compared to meteorological data from Mt. Fidelity, British Columbia, Canada, for five winters between 2005 and 2010. Forecasted precipitation amounts were generally over-estimated. The forecasted data were therefore filtered and used as input for the snow cover model. Comparison between the model output and manual observations showed that after pre-processing the input data the snow depth, new snow events and amounts were well modelled. Relevant critical layers, i.e. melt-freeze crusts and surface hoar layers were reproduced. Overall, the model chain pSNOWPACK shows promising potential as a forecasting tool for avalanche warning services in Canadian data sparse areas and could thus well be applied to similarly large regions elsewhere.

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Forcing the snow-cover model SNOWPACK with forecasted weather data

The Cryosphere ◽

10.5194/tc-5-1115-2011 ◽

2011 ◽

Vol 5 (4) ◽

pp. 1115-1125 ◽

Cited By ~ 39

Author(s):

S. Bellaire ◽

J. B. Jamieson ◽

C. Fierz

Keyword(s):

Snow Cover ◽

Snow Depth ◽

Model Comparison ◽

Weather Forecasting ◽

Single Point ◽

Weather Data ◽

Additional Information ◽

Avalanche Warning ◽

Warning Services ◽

Model Chain

Abstract. Avalanche danger is often estimated based on snow cover stratigraphy and snow stability data. In Canada, single forecasting regions are very large (>50 000 km2) and snow cover data are often not available. To provide additional information on the snow cover and its seasonal evolution the Swiss snow cover model SNOWPACK was therefore coupled with a regional weather forecasting model GEM15. The output of GEM15 was compared to meteorological as well as snow cover data from Mt. Fidelity, British Columbia, Canada, for five winters between 2005 and 2010. Precipitation amounts are most difficult to predict for weather forecasting models. Therefore, we first assess the capability of the model chain to forecast new snow amounts and consequently snow depth. Forecasted precipitation amounts were generally over-estimated. The forecasted data were therefore filtered and used as input for the snow cover model. Comparison between the model output and manual observations showed that after pre-processing the input data the snow depth and new snow events were well modelled. In a case study two key factors of snow cover instability, i.e. surface hoar formation and crust formation were investigated at a single point. Over half of the relevant critical layers were reproduced. Overall, the model chain shows promising potential as a future forecasting tool for avalanche warning services in Canadian data sparse areas and could thus well be applied to similarly large regions elsewhere. However, a more detailed analysis of the simulated snow cover structure is still required.

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The influence of the layered character of snow cover on the triggering of slab avalanches

Annals of Glaciology ◽

10.1017/s0260305500011496 ◽

1993 ◽

Vol 18 ◽

pp. 193-198 ◽

Cited By ~ 23

Author(s):

Jürg Schweizer

Keyword(s):

Finite Element Method ◽

Snow Cover ◽

Shear Failure ◽

Stability Evaluation ◽

The Finite Element Method ◽

Soft Layer ◽

Weak Layer ◽

Order Of Magnitude ◽

Practical Tool ◽

Avalanche Warning

One of the principal aims of avalanche warning is to prevent slab avalanches triggered by skiers. Other than explosives, the best practical tool for stability evaluation is the Rutschblock test. Whether the slab may be triggered by a skier depends on various slab characteristics. Important factors seem to be depth of the weak layer, slab hardness and sublayering of the slab. The stress distribution induced by a skier is calculated by the finite element method for typical snow-cover configurations. The additional shear stress is of the same order of magnitude as the shear strength of weak layers. Besides the critical weak layer — prerequisite for a slab avalanche — hard layers seem to be important. The analysis suggests that a shear failure is most probable at the transition from a hard to a soft layer. This corresponds well to observations of slab-avalanche profiles. The results may help to improve and quantify the analysis of snow profiles.

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Impacts of Fractional Snow Cover on Surface Air Temperature in the NCAR Community Atmosphere Model (NCAR-CAM2)

Engineering, Construction, and Operations in Challenging Environments ◽

10.1061/40722(153)38 ◽

2004 ◽

Author(s):

Zong-Liang Yang ◽

Guo-Yue Niu ◽

Qianru Zeng

Keyword(s):

Snow Cover ◽

Air Temperature ◽

Surface Air Temperature ◽

Community Atmosphere Model ◽

Fractional Snow Cover ◽

Atmosphere Model

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ЭКОЛОГО-ГЕОХИМИЧЕСКОЕ РАЙОНИРОВАНИЕ ТЕРРИТОРИИГ. БИРОБИДЖАНА ПО УРОВНЮ ЗАГРЯЗНЕНИЯ СНЕЖНОГО ПОКРОВА

10.33833/tig.2019.81.41.013 ◽

2019 ◽

Author(s):

V.B. Kalmanova

Keyword(s):

Heavy Metals ◽

Snow Cover ◽

Urban Area ◽

Constructive Method ◽

Comparative Characteristic ◽

Ecological State ◽

Sources Of Pollution ◽

Mobile Sources ◽

Arcview Gis ◽

Very High

В статье представлены результаты исследования экологогеохимического состояния снежного покрова как индикатора качества атмосферного воздуха г. Биробиджана. Выявлены основные природные и антропогенные факторы, предопределяющие экологическое состояние городской территории в зимний период (климатические, планировочная структура, стационарные и мобильные источники загрязнения). Определено, что выбросы основных загрязнителей во время отопительного сезона превышает летний в 6,5 раз. Проведены геохимические исследования снежного покрова на 60 экспериментальных площадках, заложенных в различных функциональных зонах города. Выявлено значительное превышение тяжелых металлов над фоновым уровнем: железа до 60, марганца до 50, меди до 40, цинка до 20, никеля до 12, свинца до 10, кобальта до 6 раз. С 2003 по 2018 годы содержание химических элементов в снеге увеличилось в 2 раза за счет мобильных источников загрязнения, ТЭЦ, котельных. Проведена сравнительная характеристика накопления тяжелых металлов в снеге за 2003 и 2018 годы и установлен ранжированный ряд загрязняющих токсичных веществ. Разработана шкала оценки загрязнения депонирующих сред по суммарному показателю концентрации тяжелых металлов, согласно которой в Биробиджане выявлено 5 уровней загрязнения снежного покрова. В целом экологическое состояние урбанизированной территории признано неудовлетворительным (8 площади территории относится к очень высокому, 14 к высокому, 21 к выше среднему, 27 к среднему уровням загрязнения, 30 к относительно чистым районам города). По полученным результатам разработана карта в программе ArcView GIS Экологогеохимическое районирование территории г. Биробиджана по уровню загрязнения снежного покрова с выделением наиболее загрязненных участков (70 от общей площади города является загрязненной). По результатам проведенных исследований предложены конструктивные методы планирования урбанизированной территории с целью улучшения ее экологического состояния: проведение геомониторинга (контроль загрязнения снежного покрова и своевременный его вывоз на специально оборудованные полигоны). Snow cover is taken as an indicator of air quality using Birobidzhan, a middlesize city in the Russian Far East, as a case study. The main natural and manmade determinants influencing the ecological state of the urban area in winter are identified: climate, a planning structure, and the stationary and mobile sources of pollution. During the heating season the emission of major pollutants exceeds the summer level by 6.5 times. The geochemical study of snow cover was performed at 60 experimental sites in different functional urban areas. A significant excess of heavy metals over the regional background level was revealed: iron up to 60 times, manganese up to 50, copper up to 40, zinc up to 20 , nickel up to 12, lead up to 10, cobalt up to 6 times. From 2003 to 2018 the content of chemical elements in snow increased in 2 times due to the mobile sources of pollution, thermal power plants, and boilers. The comparative characteristic of accumulation of heavy metals in snow for 2003 and 2018 is carried out, and the ranked number of polluting toxic substances is established. The scale of pollution assessment in depositing environments was developed using the cumulative indicator of heavy metal concentration. Five levels of snow cover pollution are found in Birobidzhan: low, moderate, above moderate, high and very high. As a whole, the ecological state of the urban area is considered as unsatisfactory (8 of the area with a very high level of pollution, 14 with high, 21 above moderate, 27 a moderate level of pollution, 30 a relatively clean area). According to the results, a map was developed in the ArcView GIS program Ecological and geochemical zoning of Birobidzhan, using the level of the snow cover pollution with the allocation of the most polluted areas (70 of the total area of the city is polluted). According to the results, a constructive method of planning in an urban area is proposed in order to improve its environmental condition: geomonitoring as a control of pollution in snow cover and its prompt removal to specially equipped landfills.

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