Pub Date : 2018-12-11DOI: 10.15356/2076-6734-2018-4-437-447
V. Popovnin, Y. Y. Sergiyevskaya
Releases of avalanches are an important factor of snow accumulation for many mountain glaciers. However, the quantitative estimate of the share of avalanche snow in the incoming part of the mass balance has not yet been standardized due to the lack of a universal methodological scheme for the calculation and collection of actual material. In rare cases, e.g. for the Djankuat Glacier in the Caucasus, this problem is partly solved. Here, the conceptual basis of the required calculations is created, and the input information has been supplied for many years by the route snow-measuring profling performed in the spring close to the date of the maximum of seasonal snow reserves and accompanied by direct feld mapping. Annually, avalanche deposits attributed to additional snow income from outside the glacier are recorded in all high-altitude morphological zones, with the exception of the lowest (< 2850 m) hypsometric belt, although in the half-century history of monitoring there were cases when snow avalanches reached it. Te volume of avalanche deposits was calculated for 15 years afer 1991/92, and each time it correlated with the gross snow accumulation of the corresponding balance year. Te contribution of snow avalanches to the income of substances on the glacier varies from 1.8 to 10.0% and averages 4.7%. Paradoxical (but only at frst glance) conclusion based on the analysis of data on volumes of avalanche and total accumulation is the feedback of these indicators (r= -0.58). It should be noted that the share of avalanche contribution to alimentation of the glacier has a more convincing feedback with accumulation and background snow content of winter (r= -0.72). Probably, the revealed tendency of increasing role of the additional avalanche alimentation in low-snow years (and vice versa) is not limited by the only reference object, and it is true for any glacier prone to the avalanche influence.
{"title":"On a feedback of the share of avalanche alimentation with a glacier accumulation","authors":"V. Popovnin, Y. Y. Sergiyevskaya","doi":"10.15356/2076-6734-2018-4-437-447","DOIUrl":"https://doi.org/10.15356/2076-6734-2018-4-437-447","url":null,"abstract":"Releases of avalanches are an important factor of snow accumulation for many mountain glaciers. However, the quantitative estimate of the share of avalanche snow in the incoming part of the mass balance has not yet been standardized due to the lack of a universal methodological scheme for the calculation and collection of actual material. In rare cases, e.g. for the Djankuat Glacier in the Caucasus, this problem is partly solved. Here, the conceptual basis of the required calculations is created, and the input information has been supplied for many years by the route snow-measuring profling performed in the spring close to the date of the maximum of seasonal snow reserves and accompanied by direct feld mapping. Annually, avalanche deposits attributed to additional snow income from outside the glacier are recorded in all high-altitude morphological zones, with the exception of the lowest (< 2850 m) hypsometric belt, although in the half-century history of monitoring there were cases when snow avalanches reached it. Te volume of avalanche deposits was calculated for 15 years afer 1991/92, and each time it correlated with the gross snow accumulation of the corresponding balance year. Te contribution of snow avalanches to the income of substances on the glacier varies from 1.8 to 10.0% and averages 4.7%. Paradoxical (but only at frst glance) conclusion based on the analysis of data on volumes of avalanche and total accumulation is the feedback of these indicators (r= -0.58). It should be noted that the share of avalanche contribution to alimentation of the glacier has a more convincing feedback with accumulation and background snow content of winter (r= -0.72). Probably, the revealed tendency of increasing role of the additional avalanche alimentation in low-snow years (and vice versa) is not limited by the only reference object, and it is true for any glacier prone to the avalanche influence.","PeriodicalId":43880,"journal":{"name":"Led i Sneg-Ice and Snow","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2018-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90761165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-11DOI: 10.15356/2076-6734-2018-4-537-551
I. Bychkova, V. Smirnov
Te methods of satellite monitoring of dangerous ice formations, namely icebergs in the Arctic seas, representing a threat to the safety of navigation and economic activity on the Arctic shelf are considered. Te main objective of the research is to develop methods for detecting icebergs using satellite radar data and high space resolution images in the visible spectral range. Te developed method of iceberg detection is based on statistical criteria for fnding gradient zones in the analysis of two-dimensional felds of satellite images. Te algorithms of the iceberg detection, the procedure of the false target identifcation, and determination the horizontal dimensions of the icebergs and their location are described. Examples of iceberg detection using satellite information with high space resolution obtained from Sentinel-1 and Landsat-8 satellites are given. To assess the iceberg threat, we propose to use a model of their drif, one of the input parameters of which is the size of the detected objects. Tree possible situations of observation of icebergs are identifed, namely, the «status» state of objects: icebergs on open water; icebergs in drifing ice; and icebergs in the fast ice. At the same time, in each of these situations, the iceberg can be grounded, that prevents its moving. Specifc features of the iceberg monitoring at various «status» states of them are considered. Te «status» state of the iceberg is also taken into account when assessing the degree of danger of the detected object. Te use of iceberg detection techniques based on satellite radar data and visible range images is illustrated by results of monitoring the coastal areas of the Severnaya Zemlya archipelago. Te approaches proposed to detect icebergs from satellite data allow improving the quality and efciency of service for a wide number of users with ensuring the efciency and safety of Arctic navigation and activities on the Arctic shelf.
{"title":"Use of satellite data for detecting icebergs and evaluating the iceberg threats","authors":"I. Bychkova, V. Smirnov","doi":"10.15356/2076-6734-2018-4-537-551","DOIUrl":"https://doi.org/10.15356/2076-6734-2018-4-537-551","url":null,"abstract":"Te methods of satellite monitoring of dangerous ice formations, namely icebergs in the Arctic seas, representing a threat to the safety of navigation and economic activity on the Arctic shelf are considered. Te main objective of the research is to develop methods for detecting icebergs using satellite radar data and high space resolution images in the visible spectral range. Te developed method of iceberg detection is based on statistical criteria for fnding gradient zones in the analysis of two-dimensional felds of satellite images. Te algorithms of the iceberg detection, the procedure of the false target identifcation, and determination the horizontal dimensions of the icebergs and their location are described. Examples of iceberg detection using satellite information with high space resolution obtained from Sentinel-1 and Landsat-8 satellites are given. To assess the iceberg threat, we propose to use a model of their drif, one of the input parameters of which is the size of the detected objects. Tree possible situations of observation of icebergs are identifed, namely, the «status» state of objects: icebergs on open water; icebergs in drifing ice; and icebergs in the fast ice. At the same time, in each of these situations, the iceberg can be grounded, that prevents its moving. Specifc features of the iceberg monitoring at various «status» states of them are considered. Te «status» state of the iceberg is also taken into account when assessing the degree of danger of the detected object. Te use of iceberg detection techniques based on satellite radar data and visible range images is illustrated by results of monitoring the coastal areas of the Severnaya Zemlya archipelago. Te approaches proposed to detect icebergs from satellite data allow improving the quality and efciency of service for a wide number of users with ensuring the efciency and safety of Arctic navigation and activities on the Arctic shelf.","PeriodicalId":43880,"journal":{"name":"Led i Sneg-Ice and Snow","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2018-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66930585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-11DOI: 10.15356/2076-6734-2018-4-448-461
O. Solomina, I. Bushueva, P. Polumieva, E. Dolgova, M. Dokukin
On the basis of dendrochronological, lichenometric and historical data with the use of Earth remote sensing materials, the evolution of the Donguz-Orun Glacier has been reconstructed over the past centuries. In this work we used aerial photographs of 1957, 1965, 1981, 1987, satellite image of 2009, as well as descriptions, photographs, maps and plans of the glacier of the 19th and 20th centuries, data of instrumental measurements of the glacier end position in the second half of the 20th – early 21st centuries, dendrochronological dating of pine on the front part of the valley, and juniper to date coastal moraines, and the results of lichenometry studies. It has been established that the Donguz-Orun Glacier in the past had several clearly marked advances about 100, 200 and more than 350 years ago, which are expressed in relief in the form of uneven-aged coastal moraines. Despite the fact that the Donguz-Orun Glacier differs from many mountain-valley glaciers of the Caucasus primarily by its predominantly avalanche feeding and a moraine cover, almost entirely covering its surface, the main periods of its advances are consistent with the known large fluctuations of mountain glaciers during the Little Ice Age in the early 20th, early 19th, and, probably, in the middle of the 17th century. However, unlike most other Caucasian glaciers, the Donguz-Orun Glacier advanced in the 1970s–2000s. Te scale of its degradation from the end of the 19th to the beginning of the 21st century is also uncharacteristic for the Caucasus: the reduction in the length for longer than a century period is only about 100 m.
{"title":"History of the Donguz-Orun Glacier from bioindication, historical, cartographic sources and remote sensing data","authors":"O. Solomina, I. Bushueva, P. Polumieva, E. Dolgova, M. Dokukin","doi":"10.15356/2076-6734-2018-4-448-461","DOIUrl":"https://doi.org/10.15356/2076-6734-2018-4-448-461","url":null,"abstract":"On the basis of dendrochronological, lichenometric and historical data with the use of Earth remote sensing materials, the evolution of the Donguz-Orun Glacier has been reconstructed over the past centuries. In this work we used aerial photographs of 1957, 1965, 1981, 1987, satellite image of 2009, as well as descriptions, photographs, maps and plans of the glacier of the 19th and 20th centuries, data of instrumental measurements of the glacier end position in the second half of the 20th – early 21st centuries, dendrochronological dating of pine on the front part of the valley, and juniper to date coastal moraines, and the results of lichenometry studies. It has been established that the Donguz-Orun Glacier in the past had several clearly marked advances about 100, 200 and more than 350 years ago, which are expressed in relief in the form of uneven-aged coastal moraines. Despite the fact that the Donguz-Orun Glacier differs from many mountain-valley glaciers of the Caucasus primarily by its predominantly avalanche feeding and a moraine cover, almost entirely covering its surface, the main periods of its advances are consistent with the known large fluctuations of mountain glaciers during the Little Ice Age in the early 20th, early 19th, and, probably, in the middle of the 17th century. However, unlike most other Caucasian glaciers, the Donguz-Orun Glacier advanced in the 1970s–2000s. Te scale of its degradation from the end of the 19th to the beginning of the 21st century is also uncharacteristic for the Caucasus: the reduction in the length for longer than a century period is only about 100 m.","PeriodicalId":43880,"journal":{"name":"Led i Sneg-Ice and Snow","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2018-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80239857","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-11DOI: 10.15356/2076-6734-2018-4-569-573
М.Ю. Москалевский, А. Я. Муравьев
Годовой прирост административно регулируемых цен и тарифов увеличился до 10,8 процента (9,7 процента месяцем ранее). Ускорение роста цен на регулируемые позиции обусловлено повышением цен на топливо, а также стоимости услуг высшего образования и связи. Кроме того, в связи с пересмотром нормативов потребления тепловой энергии на нужды горячего водоснабжения в сентябре 2018 г. выросла стоимость услуг ЖКХ. Вместе с тем в связи с окончанием летних каникул в сторону понижения была пересчитана стоимость услуг детских дошкольных учреждений.
{"title":"Полярная конференция и Гляциологический симпозиум в Сочи (сентябрь 2018 г.)","authors":"М.Ю. Москалевский, А. Я. Муравьев","doi":"10.15356/2076-6734-2018-4-569-573","DOIUrl":"https://doi.org/10.15356/2076-6734-2018-4-569-573","url":null,"abstract":"Годовой прирост административно регулируемых цен и тарифов увеличился до 10,8 процента (9,7 процента месяцем ранее). Ускорение роста цен на регулируемые позиции обусловлено повышением цен на топливо, а также стоимости услуг высшего образования и связи. Кроме того, в связи с пересмотром нормативов потребления тепловой энергии на нужды горячего водоснабжения в сентябре 2018 г. выросла стоимость услуг ЖКХ. Вместе с тем в связи с окончанием летних каникул в сторону понижения была пересчитана стоимость услуг детских дошкольных учреждений.","PeriodicalId":43880,"journal":{"name":"Led i Sneg-Ice and Snow","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2018-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66930515","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-11DOI: 10.15356/2076-6734-2018-4-552-558
V. Baklagin
Studying of characteristics of the Lake Onega ice regime and investigating of the climate influence on the formation and destruction of the ice cover requires a continuous chronological series of data on the Lake ice coverage. Ice cover is the percentage of the ice area to the total area of the lake. In 1955–1990, calculations of the ice coverage of the Lake were based on the use of the results of airborne ice reconnaissance. On average for this period, from 5 to 15 values were annually obtained, which was not enough for a comprehensive analysis of the ice coverage variability. In this paper, for the frst time, a daily series of values of the ice coverage of the Lake Onega for the period 2000–2018 had been formed basing on the results of a combined analysis of the following satellite data sets: NSIDC, NOAA NESDIS, corrected by data of the satellite MODIS sensor. Values from November to May were grouped from the above data sets without regards for years of observations, and then the regression analysis of these values made possible to create a model (a polynomial of the 8th degree) of the chronological course of the ice coverage during the period of the ice phenomena existence on the Lake Onega. Te coefcient of determination of the model is 0.74, and the error in determining the ice coverage is 21%. Te average dates of the beginning, end, and duration of periods of the formation (from November 25th to January 19th), the destruction (from April 13th to May 17th) of the ice cover, as well as the total freeze-up time (from January 20th to April 12th) on the Lake Onega for the period 2000–2018 was determined. Te period of ice phenomena on the Lake Onega on average lasts for almost half a year (175 days), of which a signifcant part of the time is a complete freeze-up (84 days). It was found that the rate of formation of the ice cover (1.76% per day) on the Lake Onega is 1.65 times smaller than the rate of its destruction (2.90% per day), which approximately corresponds to similar results obtained for the Lake Ladoga (1.5 times).
{"title":"Variability of the Lake Onega ice coverage in the period 2000-2018 according to the satellite data","authors":"V. Baklagin","doi":"10.15356/2076-6734-2018-4-552-558","DOIUrl":"https://doi.org/10.15356/2076-6734-2018-4-552-558","url":null,"abstract":"Studying of characteristics of the Lake Onega ice regime and investigating of the climate influence on the formation and destruction of the ice cover requires a continuous chronological series of data on the Lake ice coverage. Ice cover is the percentage of the ice area to the total area of the lake. In 1955–1990, calculations of the ice coverage of the Lake were based on the use of the results of airborne ice reconnaissance. On average for this period, from 5 to 15 values were annually obtained, which was not enough for a comprehensive analysis of the ice coverage variability. In this paper, for the frst time, a daily series of values of the ice coverage of the Lake Onega for the period 2000–2018 had been formed basing on the results of a combined analysis of the following satellite data sets: NSIDC, NOAA NESDIS, corrected by data of the satellite MODIS sensor. Values from November to May were grouped from the above data sets without regards for years of observations, and then the regression analysis of these values made possible to create a model (a polynomial of the 8th degree) of the chronological course of the ice coverage during the period of the ice phenomena existence on the Lake Onega. Te coefcient of determination of the model is 0.74, and the error in determining the ice coverage is 21%. Te average dates of the beginning, end, and duration of periods of the formation (from November 25th to January 19th), the destruction (from April 13th to May 17th) of the ice cover, as well as the total freeze-up time (from January 20th to April 12th) on the Lake Onega for the period 2000–2018 was determined. Te period of ice phenomena on the Lake Onega on average lasts for almost half a year (175 days), of which a signifcant part of the time is a complete freeze-up (84 days). It was found that the rate of formation of the ice cover (1.76% per day) on the Lake Onega is 1.65 times smaller than the rate of its destruction (2.90% per day), which approximately corresponds to similar results obtained for the Lake Ladoga (1.5 times).","PeriodicalId":43880,"journal":{"name":"Led i Sneg-Ice and Snow","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2018-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66930321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-11DOI: 10.15356/2076-6734-2018-4-559-568
A. N. Chetyrbotsky, A. U. Lazaryuk
Analysis of sample distributions of temperature and salinity within depths of sea ice allowed revealing a high negative correlation between temperature of the surface air layer and the salinity vertical distribution across the ice thickness. Tis situation is explained by the fact that when temperature inside the ice rises the vertically oriented pores flled with brine, and this causes increased flow of brine. But when the temperature of the thickness drops, volumes of these pores signifcantly decrease, and as a result of that stresses near the pores grow and brine is squeezed out to both above and under the ice. Comparison of individual cases of the sample salinity distributions made possible to determine that the temperature of the surface air layer signifcantly influences the freezing intensity. When developing a model of spatiotemporal dynamics of the temperature, the diffusion mechanism of its vertical distribution is adopted, where the thermal conductivity coefcient is a linear function of temperature. A computational scheme for solving the model equations had been developed. Te procedure to estimate the model parameters is given. Te results of the parameter estimations had proved the adequacy of both the sample and the model distributions. A degree of the adequacy is the correlation coefcient between the above distributions. It is shown that the numerical simulation of the spatiotemporal salinity dynamics can be performed in framework of the diffusion mechanism of the vertical distribution, where the diffusion coefcient is a linear function of temperature. Te results of the parameter estimations did also show the adequacy of both the sample and the model distributions.
{"title":"Temperature and salinity distribution of sea ice cover according to experimental and model data (case study of Novik Bay of the Sea of Japan)","authors":"A. N. Chetyrbotsky, A. U. Lazaryuk","doi":"10.15356/2076-6734-2018-4-559-568","DOIUrl":"https://doi.org/10.15356/2076-6734-2018-4-559-568","url":null,"abstract":"Analysis of sample distributions of temperature and salinity within depths of sea ice allowed revealing a high negative correlation between temperature of the surface air layer and the salinity vertical distribution across the ice thickness. Tis situation is explained by the fact that when temperature inside the ice rises the vertically oriented pores flled with brine, and this causes increased flow of brine. But when the temperature of the thickness drops, volumes of these pores signifcantly decrease, and as a result of that stresses near the pores grow and brine is squeezed out to both above and under the ice. Comparison of individual cases of the sample salinity distributions made possible to determine that the temperature of the surface air layer signifcantly influences the freezing intensity. When developing a model of spatiotemporal dynamics of the temperature, the diffusion mechanism of its vertical distribution is adopted, where the thermal conductivity coefcient is a linear function of temperature. A computational scheme for solving the model equations had been developed. Te procedure to estimate the model parameters is given. Te results of the parameter estimations had proved the adequacy of both the sample and the model distributions. A degree of the adequacy is the correlation coefcient between the above distributions. It is shown that the numerical simulation of the spatiotemporal salinity dynamics can be performed in framework of the diffusion mechanism of the vertical distribution, where the diffusion coefcient is a linear function of temperature. Te results of the parameter estimations did also show the adequacy of both the sample and the model distributions.","PeriodicalId":43880,"journal":{"name":"Led i Sneg-Ice and Snow","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2018-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66930429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-11DOI: 10.15356/2076-6734-2018-4-473-485
A. Komarov, Y. Seliverstov, P. Grebennikov, S. Sokratov
Te paper presents the results of studies aimed at investigation of the spatial and temporal variability of snow coverstructure on the basis of strength values and its variations obtained by means of the high-resolution penetrometer SnowMicroPen. Te possibilities of fast and independent from the observer identifcation of layers (including identifcation of weakened, potentially avalanche-dangerous layers) were estimated under the climatic conditions of Moscow and the Khibiny mountains. Horizontal areas with homogeneous underlying surface and vegetation were selected for the stratigraphic studies that made it possible to avoid a possible influence of slope relief and exposure from the obtained data on the spatial and temporal variability of the snow depth structure. Te analysis of the information obtained in winter seasons 2014/15 and 2016/17 allowed constructing detailed schemes of the snow cover evolution at the Moscow site as well as assessing the inter-annual and intra-seasonal variability of its structure. Afer the SnowMicroPen data were recorded in the course of the feld works carried out in winter 2015/16 on the Khibiny educational and scientifc base of the Lomonosov Moscow State University (city of Kirovsk), the 10-meter trench on the same profle was described in details, and direct data on the snow cover structure were obtained. Te strength values resulted from the above studies characterize the layers composed of crystals of various shapes and sizes, and they are considered as the frst step to methodology of operational defnition of the spatially-inhomogeneous stratigraphy and stability of snowpack without snowpit observations. Te data analysis showed high spatial and temporal variability of the structure and properties of snow cover even at a homogeneous area, usually described by a single snowpit.
{"title":"Spatio-temporal heterogeneity of the snow cover from data of the penetrometer SnowMicroPen","authors":"A. Komarov, Y. Seliverstov, P. Grebennikov, S. Sokratov","doi":"10.15356/2076-6734-2018-4-473-485","DOIUrl":"https://doi.org/10.15356/2076-6734-2018-4-473-485","url":null,"abstract":"Te paper presents the results of studies aimed at investigation of the spatial and temporal variability of snow coverstructure on the basis of strength values and its variations obtained by means of the high-resolution penetrometer SnowMicroPen. Te possibilities of fast and independent from the observer identifcation of layers (including identifcation of weakened, potentially avalanche-dangerous layers) were estimated under the climatic conditions of Moscow and the Khibiny mountains. Horizontal areas with homogeneous underlying surface and vegetation were selected for the stratigraphic studies that made it possible to avoid a possible influence of slope relief and exposure from the obtained data on the spatial and temporal variability of the snow depth structure. Te analysis of the information obtained in winter seasons 2014/15 and 2016/17 allowed constructing detailed schemes of the snow cover evolution at the Moscow site as well as assessing the inter-annual and intra-seasonal variability of its structure. Afer the SnowMicroPen data were recorded in the course of the feld works carried out in winter 2015/16 on the Khibiny educational and scientifc base of the Lomonosov Moscow State University (city of Kirovsk), the 10-meter trench on the same profle was described in details, and direct data on the snow cover structure were obtained. Te strength values resulted from the above studies characterize the layers composed of crystals of various shapes and sizes, and they are considered as the frst step to methodology of operational defnition of the spatially-inhomogeneous stratigraphy and stability of snowpack without snowpit observations. Te data analysis showed high spatial and temporal variability of the structure and properties of snow cover even at a homogeneous area, usually described by a single snowpit.","PeriodicalId":43880,"journal":{"name":"Led i Sneg-Ice and Snow","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2018-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"66929829","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-10DOI: 10.15356/2076-6734-2018-4-498-506
N. Koronkevich, A. Georgiadi, S. Dolgov, E. Barabanova, E. A. Kashutina, I. Milyukova
In recent decades, in the southern macro-slope (catchment) of Te Russian Plain, mainly within the basins of the Volga and the Don rivers, the spring flood flow decreased due to both anthropogenic and climatic factors. Of anthropogenic factors, the creation of reservoirs played a signifcant role in changing the water regime of the Volga and the Don. Another important factor, affecting the river runoff, is agricultural activities on flat interfluves and slopes. Compared with the conventional-natural period (for the Volga from 1879, and for the Don from 1876 to 1929) to the date (for the period 1930–2014), the flood flow of the Volga has been decreased by more than 4300 km3, and the Don – by almost 900 km3. Te contribution of anthropogenic factors to this decrease in the Volga basin exceeded 70%, and for the Don it was equal to 45%, while the climatic ones contributed 30 and 55%, respectively. During the period of instrumental observations on the rivers of the region, long-lasting phases of high/low water content with duration from 15–20 to 90 years or longer, caused by the climatic changes, were determined. Tese are a characteristic feature of long-term changes in flood flow (and in a runoff of other seasons) on both medium and large rivers of the southern macro-slope of the Russian Plain. Te period since early 2000s was a start of the decreased flood flow everywhere, i.e. on medium and large rivers. It is most clearly (by tens of percent) manifested in the decrease of the spring surface flow due to the following factors: more frequent thaws, reduction of the depth of soil freezing, increase of infltration, especially in the forest-steppe and steppe zones. Increase in flow of the infltration origin does only partially compensate the decrease of the flow in rivers.
{"title":"Change in snow flood flow in the southern macro-slope of the Russian Plain in the period 1930-2014","authors":"N. Koronkevich, A. Georgiadi, S. Dolgov, E. Barabanova, E. A. Kashutina, I. Milyukova","doi":"10.15356/2076-6734-2018-4-498-506","DOIUrl":"https://doi.org/10.15356/2076-6734-2018-4-498-506","url":null,"abstract":"In recent decades, in the southern macro-slope (catchment) of Te Russian Plain, mainly within the basins of the Volga and the Don rivers, the spring flood flow decreased due to both anthropogenic and climatic factors. Of anthropogenic factors, the creation of reservoirs played a signifcant role in changing the water regime of the Volga and the Don. Another important factor, affecting the river runoff, is agricultural activities on flat interfluves and slopes. Compared with the conventional-natural period (for the Volga from 1879, and for the Don from 1876 to 1929) to the date (for the period 1930–2014), the flood flow of the Volga has been decreased by more than 4300 km3, and the Don – by almost 900 km3. Te contribution of anthropogenic factors to this decrease in the Volga basin exceeded 70%, and for the Don it was equal to 45%, while the climatic ones contributed 30 and 55%, respectively. During the period of instrumental observations on the rivers of the region, long-lasting phases of high/low water content with duration from 15–20 to 90 years or longer, caused by the climatic changes, were determined. Tese are a characteristic feature of long-term changes in flood flow (and in a runoff of other seasons) on both medium and large rivers of the southern macro-slope of the Russian Plain. Te period since early 2000s was a start of the decreased flood flow everywhere, i.e. on medium and large rivers. It is most clearly (by tens of percent) manifested in the decrease of the spring surface flow due to the following factors: more frequent thaws, reduction of the depth of soil freezing, increase of infltration, especially in the forest-steppe and steppe zones. Increase in flow of the infltration origin does only partially compensate the decrease of the flow in rivers.","PeriodicalId":43880,"journal":{"name":"Led i Sneg-Ice and Snow","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2018-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90805689","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-10DOI: 10.15356/2076-6734-2018-4-462-472
R. Chernov, A. Muraviev
Climate warming in Svalbard, starting in the 1920s, caused a signifcant reduction in the mountain glaciation of the Nordenskjold Land. Te most extensive changes took place in the Western part of this territory due to the influence of the warm Spitsbergen current creating here the high temperature background. In addition, due to elevation of the level of the climatic snow line, many glaciers have actually lost the area of accumulation. From 1936 to 2017, the area of glaciers in the Western part of this region decreased by 169.5 km2 or 49.5%. Large valley glaciers and numerous small glaciers have lost the greatest area. Te relative losses of the area of glaciers were revealed to be proportional to sizes of them. In average over the past 80 years, glaciers with areas smaller 0.5 km² reduced by 76%, while big glaciers with areas larger 5 km2 – by only 34%. At present, there are 152 glaciers with a total area of 172.73±9.31 km2 in the Western territory of the Land of Nordenskjold (West of the Bolterdalen valley). According to the aerial photography of 2008–2009, the total area of glaciation of the Land of Nordenskjold covers 428 km2. High present-day rates of the retreating of local glaciers are apparently caused by extreme thinning of glacial tongues. At the same time, shrinking of glaciers located in the West of the Peninsula turned out to be more intensive than that of glaciers in its center. Although the Eastern territories receive less precipitation than glaciers near the coast of the Greenland Sea, the Eastern glaciers were found to be more resistant to reduction due to higher locations of them.
{"title":"Contemporary changes in the area of glaciers in the western part of the Nordenskjold Land (Svalbard)","authors":"R. Chernov, A. Muraviev","doi":"10.15356/2076-6734-2018-4-462-472","DOIUrl":"https://doi.org/10.15356/2076-6734-2018-4-462-472","url":null,"abstract":"Climate warming in Svalbard, starting in the 1920s, caused a signifcant reduction in the mountain glaciation of the Nordenskjold Land. Te most extensive changes took place in the Western part of this territory due to the influence of the warm Spitsbergen current creating here the high temperature background. In addition, due to elevation of the level of the climatic snow line, many glaciers have actually lost the area of accumulation. From 1936 to 2017, the area of glaciers in the Western part of this region decreased by 169.5 km2 or 49.5%. Large valley glaciers and numerous small glaciers have lost the greatest area. Te relative losses of the area of glaciers were revealed to be proportional to sizes of them. In average over the past 80 years, glaciers with areas smaller 0.5 km² reduced by 76%, while big glaciers with areas larger 5 km2 – by only 34%. At present, there are 152 glaciers with a total area of 172.73±9.31 km2 in the Western territory of the Land of Nordenskjold (West of the Bolterdalen valley). According to the aerial photography of 2008–2009, the total area of glaciation of the Land of Nordenskjold covers 428 km2. High present-day rates of the retreating of local glaciers are apparently caused by extreme thinning of glacial tongues. At the same time, shrinking of glaciers located in the West of the Peninsula turned out to be more intensive than that of glaciers in its center. Although the Eastern territories receive less precipitation than glaciers near the coast of the Greenland Sea, the Eastern glaciers were found to be more resistant to reduction due to higher locations of them.","PeriodicalId":43880,"journal":{"name":"Led i Sneg-Ice and Snow","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2018-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83329488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-10DOI: 10.15356/2076-6734-2018-4-486-497
T. B. Titkova, E. Cherenkova, V. Semenov
Te space-time dynamics of the occurrence of winter extreme events is investigated on the territory of Russia in 1970-2015 on the basis of daily observations at weather stations. It was found that a whole on the territory a noticeable increase in the occurrence of days with extremely high daily temperatures and daily precipitation and a decrease in the occurrence of extremely cold days was noted. Te most noticeable changes happened in the European part of Russia, where at the beginning of the XXI century occurrence of the extremes was greater than during the previous thirty years. Note also that at the beginning of XXI century in Southern Siberia increase of occurrences of both daily maximum and daily minimum temperature was concurrent. Tis combination appears to be caused by the increase in temperature variability in the region due to the alternation of winters with extreme frosts and warmer and wet winters. Te increase in the frequency of extremely high temperatures in the European part of Russia could have been caused by both general warming and the increased influence of AMO. An increase in the frequency of extreme high and low temperatures in the south of Siberia may be due to the formation of an anticyclonic circulation anomaly with a center near the coast of the Kara Sea, which is responsible for advection of cold air masses from the northeast. As well as cyclonic formation in southern Siberia, along the eastern periphery of which temperate latitudes can receive anomalously warm air from the subtropics.
{"title":"Regional features of changes in winter extreme temperatures and precipitation in Russia in 1970–2015","authors":"T. B. Titkova, E. Cherenkova, V. Semenov","doi":"10.15356/2076-6734-2018-4-486-497","DOIUrl":"https://doi.org/10.15356/2076-6734-2018-4-486-497","url":null,"abstract":"Te space-time dynamics of the occurrence of winter extreme events is investigated on the territory of Russia in 1970-2015 on the basis of daily observations at weather stations. It was found that a whole on the territory a noticeable increase in the occurrence of days with extremely high daily temperatures and daily precipitation and a decrease in the occurrence of extremely cold days was noted. Te most noticeable changes happened in the European part of Russia, where at the beginning of the XXI century occurrence of the extremes was greater than during the previous thirty years. Note also that at the beginning of XXI century in Southern Siberia increase of occurrences of both daily maximum and daily minimum temperature was concurrent. Tis combination appears to be caused by the increase in temperature variability in the region due to the alternation of winters with extreme frosts and warmer and wet winters. Te increase in the frequency of extremely high temperatures in the European part of Russia could have been caused by both general warming and the increased influence of AMO. An increase in the frequency of extreme high and low temperatures in the south of Siberia may be due to the formation of an anticyclonic circulation anomaly with a center near the coast of the Kara Sea, which is responsible for advection of cold air masses from the northeast. As well as cyclonic formation in southern Siberia, along the eastern periphery of which temperate latitudes can receive anomalously warm air from the subtropics.","PeriodicalId":43880,"journal":{"name":"Led i Sneg-Ice and Snow","volume":null,"pages":null},"PeriodicalIF":0.7,"publicationDate":"2018-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83559766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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