Bąble spekulacyjne jako anomalia współczesnych rynków finansowych

W artykule przedstawiono zjawisko bąbli spekulacyjnych, które jest nieodłącznym elementem współczesnych rynków finansowych. Najczęściej pod pojęciem bąbla spekulacyjnego rozumie się ruch cen aktywów, który nie sposób wyjaśnić fundamentalnymi przesłankami bądź innymi racjonalnymi czynnikami, mającymi istotny wpływ na cenę tych aktywów. W pracy skupiono się przede wszystkim na ukazaniu behawioralnego aspektu tego zjawiska. Psychologia bowiem w dobie załamania współczesnych rynków finansowych zdaje się odgrywać niebagatelną rolę. Na przykładzie bąbli spekulacyjnych, takich jak: tulipomania, bąble biotechnologiczne czy też internetowa bańka spekulacyjna, z łatwością dostrzec można takie psychologiczne aspekty tego zjawiska, jak: zachowania stadne, kaskada informacyjna, nadmierna pewność siebie, błąd post factum, iluzja sprawowania kontroli. Zjawiska te towarzyszące pojawieniu się bąbli spekulacyjnych są bardzo bliskie każdemu uczestnikowi rynku parającemu się grą na giełdzie, o której w ostatnim czasie mówi się bardzo dużo

Classification of the Tatra Mountain lakes in terms of the duration of their ice cover (Poland and Slovakia)

This paper presents the results of a classification of the Tatra lakes based on the duration of their ice cover, altitude, volume, and potential incoming solar radiation (PISR). It is embedded in the context of the impact of current climate change on the mountain environment. A digital elevation model, morphometric data, satellite imagery from the winter seasons of 2015-2017 and the Wroc#aw taxonomy method were used in the study. It was found that the order of freezing and thawing of the lakes investigated may change from year to year. The relationship between ice cover duration and altitude is clearly weakened by variations in lake volumes, with insolation having a noticeably lesser effect. Determining the duration of ice cover of the lakes over several seasons facilitates identifying the similarities and dissimilarities between them. Five groups of lakes displaying similar characteristics were identified as well as 2 groups of lakes with highly individual characteristics. Based on the data obtained, it can be concluded that the duration of ice cover on the Tatra lakes has been shortening noticeably over the last 100 years. Small high-altitude lakes seem to be most vulnerable to climate change

Conditions of spatiotemporal variability of the thickness of the ice cover on lakes in the Tatra Mountains

This research aimed to identify the impact of local climatic and topographic conditions on the formation and development of the ice cover in highmountain lakes and the representativeness assessment of periodic point measurements of the ice cover thickness by taking into consideration the role of the avalanches on the icing of the lakes. Field works included measurement of the ice and snow cover thickness of seven lakes situated in the Tatra Mountains (UNESCO biosphere reserve) at the beginning and the end of the 2017/2018 winter season. In addition, morphometric, topographic and daily meteorological data of lakes from local IMGW (Polish Institute of Meteorology and Water Management) stations and satellite images were used. The obtained results enabled us to quantify the impact of the winter eolian snow accumulation on the variation in ice thickness. This variation was ranging from several centimetres up to about 2 meters and had a tendency to increase during the winter season. The thickest ice covers occurred in the most shaded places in the direct vicinity of rock walls. The obtained results confirm a dominating role of the snow cover in the variation of the ice thickness within individual lakes