- ItemWpływ Oscylacji Północnoatlantyckiej na przepływy rzek w dorzeczu górnej Wisły(Wydawnictwo Poznańskiego Towarzystwa Przyjaciół Nauk, 2015) Wrzesiński, Dariusz; Ogór, Tomasz; Plewa, KatarzynaThis article examines the dependence between monthly and seasonal NAO indices and monthly flows of rivers in the Wisła basin down to Jagodniki. In the analysis, use was made of monthly flow data from 55 gauging stations from 1971–2010. On the basis of 156 coefficients of correlation among the variables analysed, two variants of the clustering of the gauging stations, using Ward’s method, were employed. In both, six river clusters were distinguished. In a majority of cases, the analyses showed there to be the strongest negative correlation between winter NAO indices and May to September flows of the Wisła’s left-bank tributaries. The NAO impact on the flow of the Wisła’s Carpathian tributaries is weaker, though still observable.
- ItemStability of high and low flow periods on European rivers(Wydawnictwo Poznańskiego Towarzystwa Przyjaciół Nauk, 2015) Wrzesiński, DariuszThe aim of this paper is to examine regional differences in the flow regime of European rivers. The stability of a flow regime is defined as the regularity of high and low flow periods during a year (Corbus and Stanescu, 2004). The first, second, and third maximum and minimum values of the mean monthly flows during the year served as regime characteristics, i.e. descriptors of the regime phases. A series of monthly discharges recorded during the years 1951–1990 at 510 stations on 369 European rivers were analysed. The coefficient of stability used in the analysis enables an extension of classical hydrological regime analysis. The proposed approach allows not only to establish the term of high and low flow periods of the river, but it also shows the regularity (stability) of their occurrence.
- ItemKontynentalizm termiczny w Europie(Wydawnictwo Poznańskiego Towarzystwa Przyjaciół Nauk, 2015) Witek, Michał; Bednorz, Ewa; Forycka-Ławniczak, HannaFive indices of thermal continentality were computed for 84 stations in Europe and shown in the maps. The thermal continentality in Europe is spatially variable and increases eastward and southward from the northwestern shores towards Asia. Continental features are distinct in the interior of the Iberian Peninsula and in the northeastern part of the Scandinavian Peninsula, despite their small distance from the Atlantic Ocean. Most continentality indices (Chromow’s, Ewert’s, Conrad’s, Johansson-Ringleb’s) reveal a similar spatial pattern of thermal continentality in Europe, and they allow the continent to be divided into a western and eastern part along meridian 20–25°E. Marsz’s index, which takes into consideration the level of oceanity, indicates a narrow zone along the northwestern shore as oceanic and the remaining part of Europe as continental.
- ItemWizualizacja dynamiki zmian liczby uczestników imprezy masowej z wykorzystaniem dronów(Wydawnictwo Poznańskiego Towarzystwa Przyjaciół Nauk, 2015) Smaczyński, MaciejCurrently the fastest growing segment of equipment for acquisition of photogrammetric images is drones. This article examines the possibilities and the effectiveness of such devices to obtain images during mass events at various time intervals. The aim was to design a visualisation of the dynamics of change in the number of participants of mass events. At the same time, the paper presents an attempt to systematise the process of acquiring data using this type of Unmanned Aerial Vehicle (UAV).
- ItemAnaliza wybranych sytuacji synoptycznych związanych z ekstremalnym opadem w latach 2011-2013 nad obszarem Łodzi(Wydawnictwo Poznańskiego Towarzystwa Przyjaciół Nauk, 2015) Radziun, WojciechThe aim of the study is to analyse the maximum daily rainfall during selected synoptic situations in summer from the period 2011–2013 in Łódź. In this study, data collected from fourteen rain gauges belonging to the Łódź Infrastructure Company were used. The measurement sites were evenly distributed within the city and rainfall was recorded every 5 minutes. The study analysed five synoptic situations during which the observed day totals in the city exceeded 20 mm. The highest rainfall in Łódź occured during days featuring the passage of weather fronts, mostly cold. The maximum rainfall was observed in the southern or south-western part of the city. In four cases, south-western cyclonic circulation occurred, and in such conditions the highest rainfall was recorded in the southern part of the city and diminished towards the north. This unusual trend may be related to the terrain elevation, as the terrain in Łódź slopes north-east to southwest.