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Number of results: 5
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Abstract

The aim of this study was to provide an estimation of climate variability in the Hornsund area in Southern Spitsbergen in the period 1976-2100. The climatic variables were obtained from the Polar-CORDEX initiative in the form of time series of daily air temperature and precipitation derived from four global circulation models (GCMs) following representative concentration pathways (RCP) RCP 4.5 and RCP 8.5 emission scenarios. In the first stage of the analysis, simulations for the reference period from 1979 to 2005 were compared with observations at the Polish Polar Station Hornsund from the same period of time. In the second step, climatic projections were derived and monthly and annual means/sums were analysed as climatic indices. Following the standard methods of trend analysis, the changes of these indices over three time periods - the reference period 1976-2005, the near-future period 2021-2050, and far-future period 2071-2100 - were examined. The projections of air temperature were consistent. All analysed climate models simulated an increase of air temperature with time. Analyses of changes at a monthly scale indicated that the largest increases were estimated for winter months (more than 11°C for the far future using the RCP 8.5 scenario). The analyses of monthly and annual sums of precipitation also indicated increasing tendencies for changes with time, with the differences between mean monthly sums of precipitation for the near future and the reference period similar for each months. In the case of changes between far future and reference periods, the highest increases were projected for the winter months.
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Authors and Affiliations

Marzena Osuch
Tomasz Wawrzyniak
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Abstract

The thermal state of permafrost is a crucial indicator of environmental changes occurring in the Arctic. The monitoring of ground temperatures in Svalbard has been carried out in instrumented boreholes, although only few are deeper than 10 m and none are located in southern part of Spitsbergen. Only one of them, Janssonhaugen, located in central part of the island, provides the ground temperature data down to 100 m. Recent studies have proved that significant warming of the ground surface temperatures, observed especially in the last three decades, can be detected not only just few meters below the surface, but reaches much deeper layers. The aim of this paper is evaluation of the permafrost state in the vicinity of the Polish Polar Station in Hornsund using the numerical heat transfer model CryoGrid 2. The model is calibrated with ground temperature data collected from a 2 m deep borehole established in 2013 and then validated with data from the period 1990-2014 from five depths up to 1 m, measured routinely at the Hornsund meteorological station. The study estimates modelled ground thermal profile down to 100 m in depth and presents the evolution of the ground thermal regime in the last 25 years. The simulated subsurface temperature trumpet shows that multiannual variability in that period can reach 25 m in depth. The changes of the ground thermal regime correspond to an increasing trend of air temperatures observed in Hornsund and general warming across Svalbard.
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Authors and Affiliations

Tomasz Wawrzyniak
Marzena Osuch
Jarosław Napiórkowski
Sebastian Westermann
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Abstract

River intermittence was studied based on data from hydrological monitoring in Poland. We screened the entire state database and two another data sources applying the criterion for zero-flow event: discharge less than 0.0005 m 3∙s –1, and found five intermittent rivers with catchment area from 9.2 to 303.7 km 2. We aimed at finding associations between intermittence and climatic driving forces (temperature and precipitation), and between intermittence and anthropogenic activity. We used the Spearman correlation coefficient, circular statistics, and statistical tests for trend.
The concentration of zero-flow days, mostly in summer, and the decreasing trend in the standardised precipitation evapotranspiration index ( SPEI) in all catchments at various aggregation levels, and an increasing trend in the total number of zero-flow days and in the maximum length of zero flow events in two rivers, were detected. The strong negative correlation (–0.62 ≤ ρ < 0) between intermittence and the SPEI backward lagged in time showed that intermittence resulted from prolonged deficits in climatic water balance due to increasing evapotranspiration. The reaction of the Noteć catchment, amplified by the anthropogenic pressure (brown coal mines), was reflected in the atypical shape of the rose diagram and in inhomogeneities in river discharges.
The results show that the rose diagram can serve as an indicator of the degree of anthropogenic impact on runoff conditions.

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Authors and Affiliations

Agnieszka Rutkowska
1
ORCID: ORCID
Marzena Osuch
2
ORCID: ORCID
Mirosław Żelazny
3
ORCID: ORCID
Kazimierz Banasik
4 5
ORCID: ORCID
Mariusz Klimek
3
ORCID: ORCID

  1. University of Agriculture in Krakow, Department of Applied Mathematics, Balicka St, 253C, 30-198 Kraków, Poland
  2. Institute of Geophysics Polish Academy of Sciences, Warsaw, Poland
  3. Jagiellonian University in Kraków, Institute of Geography and Spatial Management, Kraków, Poland
  4. Warsaw University of Life Sciences – SGGW, Department of Water Engineering and Applied Geology, Warsaw, Poland
  5. Institute of Technology and Life Sciences – National Research Institute, Falenty, Poland
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Abstract

This article presents the results of a geophysical survey from which detailed images of glacial and periglacial landforms and subsurface structures were obtained. Sediments and landforms on newly deglaciated terrain can be used to reconstruct the extent and character of glaciers in the past and add to the understanding of their response to climate and environmental changes. To derive spatial information from complex geomorphological terrain, joint interpretation of three non-intrusive geophysical methods were applied: Electrical Resistivity Tomography (ERT), Ground Penetrating Radar (GPR), and time-lapse Seismic Tomography. These were used to identify subsurface structures in the forefield of the retreating Hans Glacier in SW Spitsbergen, Svalbard. Three main zones were distinguished and described: outwash plain, terminal moraine from the last glacial maximum, and glacial forefield proximal to the glacier front. Geophysical profiles across these zones reveal information on glacio-fluvial sediment thickness and structure, ice thickness and structure, and bedrock topography. The freezing-thawing effect of the active layer has a strong and deep impact, as demonstrated by variations in VP (P-wave velocity) in the obtained outcomes. The results are discussed in the context of the current climate in Svalbard. This study provides a snapshot of ground parameters and the current state of the subsurface in southern Spitsbergen. The boundary between sediment-bedrock layers was estimated to be from 5 to 20 m in depth. It is the first such extensive description of periglacial structures in the forefield of the Hans Glacier, utilising the longest ERT profile (1500 m) in Svalbard together with deep GPR and precise seismic tomography.
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Authors and Affiliations

Artur Marciniak
1
ORCID: ORCID
Marzena Osuch
1
ORCID: ORCID
Tomasz Wawrzyniak
1
ORCID: ORCID
Bartosz Owoc
1
ORCID: ORCID
Wojciech Dobiński
2
ORCID: ORCID
Michał Glazer
2
Mariusz Majdański
1
ORCID: ORCID

  1. Institute of Geophysics, Polish Academy of Sciences, Warsaw, 01-452, Poland
  2. Faculty of Natural Sciences, University of Silesia, Sosnowiec, 41-200, Poland
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Abstract

An analysis of a suite of climatological indices was undertaken on the basis of long-term (1979–2019) climatological data from the Polish Polar Station in Hornsund, SW Spitsbergen. It was followed by an attempt to assess the scale of their impact on the local environment. The temperature and precipitation indices were based on percentiles of the variables calculated for a population of daily values from the climate normals for 1981–2010. A greater share of both cyclonic and anticyclonic circulations from the S and SW sectors, forcing the advection of warm air masses from the south, was decisive for the trends of change in comparison with the long-term mean. Both extreme precipitation and drought events depend on the 500 hPa geopotential height and precipitable water anomalies, determined by the baric field over the North Atlantic. Climate changes impact on the dynamics of local geoecosystems by causing faster glacier ablation and retreat, permafrost degradation, intensification of the hydrological cycle in glaciated and unglaciated catchments, and changes in the condition and growth of tundra vegetation.
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Authors and Affiliations

Krzysztof Migała
1
ORCID: ORCID
Elżbieta Łepkowska
2
ORCID: ORCID
Marzena Osuch
3
ORCID: ORCID
Łukasz Stachnik
1
ORCID: ORCID
Tomasz Wawrzyniak
3
ORCID: ORCID
Dariusz Ignatiuk
2
ORCID: ORCID
Piotr Owczarek
1
ORCID: ORCID

  1. Institute of Geography and Regional Development, University of Wroclaw, Plac Uniwersytecki 1, 50-137 Wroclaw, Poland
  2. Institute of Earth Sciences, Faculty of Natural Sciences, University of Silesia in Katowice, ul. Będzińska 60, 41-200 Sosnowiec, Poland
  3. Institute of Geophysics, Polish Academy of Sciences, ul. Księcia Janusza 6 , 01-452 Warszawa, Poland

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