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Abstrakt

Lacustrine deposits from Ortel Królewski II (Eastern Poland) represent the Holsteinian Interglacial (MIS 11c). They are characterized by an extremely rich occurrence of ostracod and mollusc fauna. Collected samples represent pre-optimal part of the Holsteinian Interglacial corresponding to Picea–Alnus, Taxus and Pinus–Larix zones. Based on ostracod assemblage analysis a depth of the paleolake, the energy of the environment and the average January and July air temperature were reconstructed. Ostracods from Ortel Królewski II indicate a lake with possible periodic overflow sur- rounded by periodically flooded grasslands, which existed in the study area during the pre-optimal part of Holsteinian Interglacial.
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The article discusses changes in Polish regulations concerning assessment of the climate hazard in underground mines. Currently, the main empirical index representing the heat strain, used in qualification of the workplace to one of the climate hazard levels in Poland is the equivalent climate temperature. This simple heat index allows easy and quick assessment of the climate hazard. To a major extent, simple heat indices have simplifications and are developed for a specific working environments. Currently, the best methods used in evaluation of microclimate conditions in the workplace are those based on the theory of human thermal balance, where the physiological parameters characterising heat strain are body water loss and internal core temperature of the human body. The article describes the results of research on usage of equivalent climate temperature to heat strain evaluation in underground mining excavations. For this purpose, the numerical model of heat exchange between man and his environment was used, taken from PN-EN ISO 7933:2005. The research discussed in this paper has been carried out considering working conditions and clothing insulation in use in underground mines. The analyses performed in the study allowed formulation of conclusions concerning application of the equivalent climate temperature as a criterion of assessment of climate hazards in underground mines.
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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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Climate atlases summarize large sets of quantitative and qualitative data and are results of complex analytical cartographic work. These special geographical publications summarize long term meteorological observations, provide maps and figures which characterise different climate elements. Visual information is supplemented with explanatory texts. A lot of information on short and long term changes of climate elements were provided in published Lithuanian atlases (Atlas of Lithuanian SDR, 1981; Climate Atlas of Lithuania, 2013), as well as in prepared but unpublished Lithuanian Atlas (1989) and in upcoming new national atlas publications (National Atlas of Lithuania. 1 st part, 2014). Climate atlases has to be constantly updated to be relevant and to describe current climate conditions. Comprehensive indicators of Lithuanian climate are provided in different cartographic publications. Different time periods, various data sets and diverse cartographic data analysis tools and visualisation methods were used in these different publications.
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A sediment core, 350 cm long recovered from Młynek Lake, northern of Poland (Warmia and Masuria Region) was analyzed with respect to their content of diatoms and chrysophyte cysts. The aim was to reconstruct the lake water level and climatic changes during the past 2500 years. The recognized diatom assemblages displayed marked floristic changes along the sediment core samples. The main change in diatom composition consists of a shift from an assemblage dominated by benthic Fragilaria sensu lato species through marked intervals to a planktonic one in distinct zones. A high proportion of benthic to plankton taxa has been reported as indicative for a lowering of the lake level with long ice cover in a cold dry climate and a shift from benthic to planktonic diatom taxa reflects arising water level with longest growing season and reduced ice cover on the lake during a warm wet climate. Multivariate statistical analysis included hierarchical ascending clustering distinguished four diatom ecological groups. The analyzed core section was divided into 11 diatom zones according to a distribution of ecological groups and variation in abundance of dominant species supported by 14C data. The results displayed a developmental history of the Młynek Lake that can be divided into 6 main phases of alternating warm wet and cold dry shifts. A distinct dominance of planktonic eutrophic indicator diatoms accompanied by a low abundance of chrysophyte cysts indicates increased lake trophicity and a general trend for the increasing anthropogenic impact.
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It is contended that, in essence, climate policy is sustainable development policy, given that it postulates the use of renewable resources, and an increase in the effectiveness of use of non-renewable ones. Furthermore, it serves the security of future generations more than present ones; for while unfavourable impacts of climate change are already making their presence felt, truly negative consequences of considerable signifi cance are likely to be more of a matter for the second half of the present century. This is why, in analysing the evolution of the approach to climate policy through the late 20th century and into the 21st, it is also possible to appraise changes in the approach to the sustainable-development concept. This article has therefore sought to offer the author’s analysis of how the approach to sustainable development has evolved, by reference to Poland’s climate policy from 1988 through to 2016. As this is done, an attempt is also made to identify the conditioning that has decided upon and will go on determining the shape of national policy in this domain. Climate policy in Poland has been developing since the early 1990s. At the outset, it was not a source of controversy, with the consequence that the country rather rapidly signed up to and then ratifi ed the Kyoto Protocol to the UN Framework Convention on Climate Change. However, as early as in the late 1990s, reservations began to be expressed, to the effect that actions to protect the climate might pose a threat to Poland’s economy. A key turning point as regards the approach came with the growing dispute over the EU 2020 Climate and Energy Package. It was also at this time that a thesis began to take shape, holding that the goals of climate policy where at best unfavourable and at worst dangerous for Poland. This approach in fact held sway in successive years, leaving this country’s cooperation with the EU over this matter severely hindered. The main reason for this change of approach to climate policy can be considered to lie in the politicisation thereof, and hence the increasing dominance of the short-term interests of the Polish political elite over either the public interest or the security of future generations.
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A 2.5−metre−long marine core from Isvika bay in Nordaustlandet (80 ° N, 18 ° E) was AMS 14 C dated and analysed for its sedimentological and magnetic parameters. The studied record was found to cover the entire Holocene and indicates major turnovers in the palaeohydrography and sedimentary depositional history. The area was deglaciated at around 11,300 BP. The early Holocene has indications of rapid melting of glaciers and frequent deposition of ice−rafted debris (IRD). The climatic optimum terminated with a probable glacier re−advance event occurring ca. 5800 cal BP. This event caused the deposition of a diamicton unit in Isvika bay, followed by a shift towards a colder and a more stratified hydrographic set − ting. The reduction in IRD indicates gradual cooling, which led to the stratification of the bay and eventually to more persistent fast sea−ice conditions by 2500 cal BP. For the last 500 years, Isvika has again been seasonally open.
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Climate change has been affecting plants over the last century and caused changes in life history features such as the flowering time. Herbarium specimens provide a snapshot of the past environmental conditions during their collection. The collection date in a herbarium specimen is a good proxy to determine the flowering period (phenology). In this study, phenological data from subarctic plant specimens collected over 100 years were gathered by using one of the largest herbarium databases in the World. The collection dates of 7146 herbarium specimens were analyzed and significant shifts in the phenology of subarctic plants were detected. In this study, most of the analyzed 142 species in a subarctic biogeographic region tended to flower earlier in the 1950–2018 period compared to the 1900–1949 as a possible result of the climate change. Flowering time shifted from 8 to 26 days in some species. Changes in flowering time may alter species interactions, community composition, and species distribution in a region. Therefore, results of this study may shed light on the possible shifts in phenology and plant responses under the climate change.
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This paper presents the first results of measurements of global solar radiation, albedo, ground surface and 2−m air temperature, relative humidity, and wind speed and direction carried out in the central part of Spitsbergen Island in the period 2008–2010. The study site was located on the coastal ice−free zone of Petuniabukta (north−western branch of Billefjorden), which was strongly affected by local topography, character of the ground surface, and sea ice extent. Temporal analysis of the selected meteorological parameters shows both strong seasonal and inter−diurnal variation affected by synoptic−scale weather systems, channelling and drainage effects of the fjords and surrounding glaciers. The prevailing pattern of atmospheric circulation primarily determined the variation in global solar radiation, wind speed, ground surface and 2−m air temperatures. Furthermore, it was found that thermal differences between Petuniabukta and the nearest meteorological station (Svalbard Lufthavn) differ significantly due to differences in sea ice concentrations and ice types in the fjords during the winter and spring months.
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How environmental conditions influence current distributions of organisms at the local scale in sensitive High Arctic freshwaters is essential to understand in order to better comprehend the cascading consequences of the ongoing climate change. This knowledge is also important background data for paleolimnological assessments of long-Term limnoecological changes and in describing the range of environmental variability. We sampled five limnologically different freshwater sites from the Fuglebergsletta marine terrace in Hornsund, southern Svalbard, for aquatic invertebrates. Invertebrate communities were tested against non-climatic environmental drivers as limnological and catchment variables. A clear separation in the communities between the sites was observed. The largest and deepest lake was characterized by a diverse Chironomidae community but Cladocera were absent. In a pond with marine influence, crustaceans, such as Ostracoda, Amphipoda, and calanoid Copepoda were the most abundant invertebrates. Two nutrient-rich ponds were dominated by a chironomid, Orthocladius consobrinus, whereas themost eutrophic pond was dominated by the cladoceran Daphnia pulex, suggesting decreasing diversity along with the trophic status. Overall, nutrient related variables appeared to have an important influence on the invertebrate community composition and diversity, the trophic state of the sites being linked with their exposure to geese guano. Other segregating variables included water color, presence/absence of fish, abundance of aquatic vegetation and lake depth. These results suggest that since most of these variables are climate-driven at a larger scale, the impacts of the ongoing climate change will have cumulative effects on aquatic ecosystems.
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Thirty-two species of echinoderms from epibenthic sledges, dredges, scuba diving, and other samples (in total: 467 samples and c. 20 000 specimens) from fjords and coastal waters off Spitsbergen were analysed between 1996 and 2014. The most numerous group of echinoderms in the coastal waters off Spitsbergen is brittle stars (78% of the total individuals). The echinoderms do not form any clear assemblages according to depth or distance from glacial sedimentation and substrate. Some species prefer hard bottom (Strongylocentrotus droebachiensis) or water free from glacial suspensions (Ophiopholis aculeata). In contrast to the species listed above, we also found opportunistic species such as the starfish Urasterias lincki and the brittle star Ophiocten sericeum. These two species are distributed quite uniformly, regardless of the environmental factors. The majority of the species prefer a soft bottom below 200 m.
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Improving energy efficiency is key to moving toward sustainable development. It contributes to the reduction of energy consumption and carbon emissions, as well as to climate change mitigation. Indicators of energy efficiency play an important role in this field because their improvement is targeted by policy makers. Indicators based on the ratio between energy consumption and gross domestic product (GDP) are currently used by multiple key organizations, including Eurostat and the World Bank, as the main energy efficiency indicators. This study examines the most widely used indicators and identifies their deficiencies. Over the last decades, these indicators tend to show a continuous strong improvement, signifying positive progress toward energy efficiency, even in cases when the physical consumption of energy has increased significantly. This phenomenon is based on GDP adjustment. The energy intensity of economies, used currently to measure energy efficiency, masks problems and has led to the green labeling of wealthier economies. An analysis of energy efficiencies reported for multiple countries and the structure of their energy spending shows that the reported values are counterproductive for comparing economies in the context of environmental protection. The indicators sanction economies with low energy consumption and low or moderate GDP. The economies belonging to the group of the largest energy spenders per capita are labeled highly efficient because of GDP adjustment. Decision makers are therefore prompted to focus on GDP growth even at the cost of a major increase in energy consumption. An additional problem in the indicators is that they do not properly model international trade. The responsibility for energy spending is shifted toward the producers of energy-intensive goods and services. Energy intensity is a useful indicator to measure the resistance of an economy to the volatilities of energy prices. However, the challenges in the fields of environmental pollution and climate change are related to physical processes and energy consumption rather than to changes in the GDP or the monetary valuation of products and services. Indicators measuring energy efficiency as GDP per unit of energy use are inadequate and misleading as principal tools to measure energy efficiency.
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Rock glaciers are lobate or tongue-shaped landforms which consist of rock debris and have either an ice core or an ice-cemented matrix. Characteristics such as the landscape setting, morphology, material and current geomorphological state are universally used to classify rock glaciers. In Antarctica, rock glaciers have only been surveyed on the Antarctic Peninsula, Ellsworth Mountains and in Victoria Land. This paper presents the first data on the identification and description of rock glaciers in the Jutulsessen nunataks, Dronning Maud Land, East Antarctica. The rock glaciers in the Jutulsessen exhibit a variety of morphologies and states. Our data suggests that the rock glaciers in Brugdedalen and Jutuldalen are active, while the features at Vassdalen and Grjotlia are considered inactive, and a feature at Grjotøyra is considered relict. The described rock glaciers do not fit into existing classification systems and appear to be different to alpine, Arctic and Andean rock glaciers. They further present examples that fit both the ‘glaciogenic’ and ‘permafrost’ development theories.
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Dynamic climate changes have become noticeable in recent decades, especially in the vulnerable region of the West Antarctic. The relatively simple food web of this area relies on krill – Euphausia superba . Presumably, as a result of climatic fluctuations, a de− crease in the number of this crustacean has been recorded, followed by an increase in the population of the gelatinous zooplankter Salpa thompsoni . In the research presented herein, population and morphometric analyses of Salpa thompsoni have been conducted. Specimens for this research were collected from the Drake Passage, using a Bongo net in the summer season of 2010. It has been found that the horizontal distribution of this gelatinous zooplankter was significantly irregular (Kruskal−Wallis test, p < 0.001). In the northern part of the investigated area, both blastozooids and oozooids were recorded, which confirms the dynamic development of this species. The central part of the Drake Passage was characterized by the dominance of blastozooids, with embryos found at different stages of the development. Only in the region of the South Shetland Islands, the salpid population was characterized by reduced or even stopped reproduction. The immense reproductive efficiency observed in the Salpa thompsoni population was mostly induced by the favourable thermal conditions. These observations may suggest that the ongoing climat changes in the West Antarctic will promote the population expansion of this species.
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Landscape changes of the Gåsbreen glacier and its vicinity since 1899 are described. Maps at 1:50 000 scale of changes of the glacier's elevation and extent for the periods 1938-1961, 1961-1990, 1990-2010, and 1938-2010 are analyzed in comparison with results of the authors' field work in the summer seasons 1983, 1984, 2000, 2005 and 2008. During all the 20th century, the progressive recession of the glacier revealed in a dramatic decrease in the thickness of its lower part, with a small reduction of its area and length. However, further shrinkage produced significant shortening and reduction in area which resulted in final decline of the Goësvatnet glacial dammed lake in 2002. Hence, the lowest (and very thick, up to 150-160 m) part of the former glacier tongue and dammed lake were transformed into a new terraced river valley south of the glacier and a typical marginal zone with glacial landforms north of the glacier. Since 1961, the equilibrium line altitude of the Gåsbreen glacier has risen from ca 350 to ca 500 m a.s.l. and now is located below the very steep rocky walls of the Mehesten mountain ridge, 1378 m a.s.l. Hence, the glacier is being fed by snow avalanches from these rocky walls and much more snow melts during the warmer summer seasons, stimulating a quicker recession of the lowest part of the glacier. This recession may be stopped only by significant climate cooling or increase in snow.
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Vegetation succession in front of five retreating glaciers was studied using phytosociological relevés (60) located at different distances between the Little Ice Age (LIA) moraines and the present glacier fronts around Petunia Bay. Approximate dating of succession stages was based on a study of the changing position of glacier fronts in the past approximately 100 years. The described succession corresponds to the uni−directional, non−replacement model of succession. All constituent species, except one, present in the nearby old tundra have colonized the glacier forelands since the end of the LIA. The first species appeared about 5 years after deglaciation. The latest succession stages closely resemble the old tundra.
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