Changes of the thermal conditions in the selected polish cities

Opracowanie przedstawia fluktuacje średniej maksymalnej i minimalnej temperatury powietrza w dwóch punktach pomiarowych w Krakowie i w Warszawie (centrum miasta, obszar zamiejski). Zmienność średnich temperatur w stosunku do miesięcznych, maksymalnych i minimalnych wartości przebadano dla pór roku zdefiniowanych w sposób standardowy: zima (grudzień-luty) i lato (czerwieo-sierpień). Przy analizie zmienności wyeliminowano krótkotrwałe fluktuacje poprzez wygładzenie z zastosowaniem metody średnich ruchomych 5-letnich.The paper presents the fluctuation of mean maximum and minimum air temperature of two measurement points in Cracow and Warsaw (city centre, rural area). Variability of mean temperatures in relation to monthly, maximum and minimum values was studied for seasons defined in a standard way: winter (December-February) and summer (June-August). In the analysis of variability, short-term fluctuations have been eliminated by smoothing, using the method of 5-year moving averages

Effect of relief and land use on heat stress in Kraków, Poland

Heat stress in urban areas is controlled mainly by the impact of anthropogenic land use on the active surface heat balance. This paper shows the role of land form superimposed on the land-use impact, using the example of Krakow, Poland. The city is located in a concave land form, on the Wisla (Vistula) River. The automatic measurements of air temperature and humidity were realised in Kraków from April to October, in the years 2010-2012. For the day time conditions, ANOVA test and Tukey’s test showed significant differences in the number of very hot days and number of heat waves, between urban areas in the valley and rural areas, both in the valley and on the slope. For the night time, significant differences were found for the number of tropical nights, not only between urban and rural areas, but also between urban areas located in various landforms and between urban areas in the valley floor and rural areas located in various landforms. Both urban and rural measurement points located in the river valley floor experienced the highest numbers of very hot days, heat waves and extreme air temperature duration. For measurement points elevated about 50 m above the valley floor, the indices’ values were lower by about 50 %

The year-long unprecedented European heat and drought of 1540 - a worst case

The heat waves of 2003 in Western Europe and 2010 in Russia, commonly labelled as rare climatic anomalies outside of previous experience, are often taken as harbingers of more frequent extremes in the global warming-influenced future. However, a recent reconstruction of spring-summer temperatures for WE resulted in the likelihood of significantly higher temperatures in 1540. In order to check the plausibility of this result we investigated the severity of the 1540 drought by putting forward the argument of the known soil desiccation-temperature feedback. Based on more than 300 first-hand documentary weather report sources originating from an area of 2 to 3 million km2, we show that Europe was affected by an unprecedented 11-month-long Megadrought. The estimated number of precipitation days and precipitation amount for Central and Western Europe in 1540 is significantly lower than the 100-year minima of the instrumental measurement period for spring, summer and autumn. This result is supported by independent documentary evidence about extremely low river flows and Europe-wide wild-, forest- and settlement fires. We found that an event of this severity cannot be simulated by state-of-the-art climate models

Interdyscyplinarne aspekty nauk o zdrowiu

Praca recenzowana / Peer-reviewed pape

Prediction of hydrological extremes by air circulation indices

The study of air circulation variability is important for a better understanding of river runoff. Research resented in this paper describes an attempt to find a link between air circulation on a large regional scale, and hydrological extremes of Carpathian river discharges in warm and cold seasons. The relationship between the North Atlantic Oscillation in winter, the Scandinavian baric system, and maximum and minimum river discharges was investigated over the period 1951-2000. Multiple correlation analysis was used. Some interesting relationships were found and multiple correlation formulae were developed for a few Carpathian basins. They may be used for hydrological forecasts of Carpathian extreme river discharges and they may allow the implementation of a warning system for extreme river event

Monthly, seasonal and annual temperature reconstructions for Central Europe derived from documentary evidence and instrumental records since AD 1500

Monthly temperature series for Central Europe back to AD 1500 are developed from documentary index series from Germany, Switzerland and the Czech Republic (1500-1854) and 11 instrumental temperature records (1760-2007). Documentary evidence from the Low Countries, the Carpathian Basin and Poland are used for cross-checking for earlier centuries. The instrumental station records are corrected for inhomogeneities, including insufficient radiation protection of early thermometers and the urban heat island effect. For overlapping period (1760-1854), the documentary data series correlate with instrumental temperatures, most strongly in winter (86% explained variance in January) and least in autumn (56% in September). For annual average temperatures, 81% of the variance is explained. Verification statistics indicate high reconstruction skill for most months and seasons. The last 20 years (since 1988) stand out as very likely the warmest 20-year period, accounting for the calibration uncertainty and decreases in proxy data quality before the calibration period. The new reconstruction displays a previously unobserved long-term decrease in DJF, MAM and JJA temperature variability over last five centuries. Compiled monthly, seasonal and annual series can be used to improve the robustness of gridded large-scale European temperature reconstructions and possible impact studies. Further improvement of the reconstruction would be achieved if documentary data from other European countries are further developed.</p