THE USE OF THE TEMPORAL OSCILLATION MODEL TO ASSESS VARIABILITY OF PRECIPITATION

The article presents the variability of precipitation based on the temporal oscillation model. Series of monthly precipitation totals from the years 1955–1980 were used for the analysis. The detailed research referred to the selected 10 measurement stations in central Poland and 17 in southern Poland. Data series from all the measurement stations were verified in terms of their statistical homogeneity. Furthermore, in accordance with the model guidelines, the tendency was assessed. This was followed by calculation of seasonal and accidental oscillations of precipitation. The results were used to present the variability of precipitation in the two areas studied. The measurement stations in southern Poland showed a much higher mean variation of seasonal oscillations of monthly precipitation. Accidental precipitation, however, is much more significant for the total variability of precipitation in southern Poland

The variability of maximum daily precipitation and the underlying circulation conditions in Kraków, southern Poland

This article studies the intra-annual and long-term variability in the maximum daily precipitation totals and their association with atmospheric circulation in Kraków. It investigates daily precipitation maxima by year and by month. The research is based on daily precipitation totals in the years 1863-2021 and draws on the calendar of atmospheric circulation types by Niedźwiedź. It examines the frequency of precipitation maxima in individual months and their variation from one year to another. No statistically significant trend of change in precipitation over the study period has been found. All annual maximum daily precipitation totals in Kraków fall into the category of heavy precipitation (>10 mm), and almost 99% qualify as very heavy (>20 mm). In the summer months, these are about 3-4 times higher than in winter. The share of the daily precipitation maximum in the monthly total exceeds 30% in all months. The maximum daily precipitation occurring on 5 August 2021 was the highest in the period that extends from the start of instrumental measurements. The study period saw 12 cases of maximum precipitation that belong to "flood-inducing" categories (over 70 mm/day). Such cases of the very heaviest precipitation occurred in cyclonic situations: Cc, Bc, Nc, NEc, Ec and SEc. Most spring and summer maxima were seen on days with a cyclonic circulation. The instances of high daily precipitation in the Kraków area led to the flooding of residential and historic buildings, as well as of municipal infrastructure

Anomalnie wysokie miesięczne opady atmosferyczne w Polskich Karpatach i na ich przedpolu (1881–2010)

Anomalously high monthly precipitation totals in the Polish Carpathian Mountains and their foreland (1881–2010)The study addresses the problem of river flooding and other dangerous natural processes as well as phenomena resulting from persistent heavy rainfall. Annual and multi-annual records of anomalously heavy precipitation were investigated using data from 16 weather stations in the Polish Carpathian Mountains and their foreland from the period 1881–2010. The anomalously high precipitation was studied in terms of its annual and multi-annual pattern, time of occurrence, spatial extent and the coinciding atmospheric circulation. The anomalously high monthly totals were defined as those, which exceeded the upper quartile plus 1.5x the interquartile range. It was found that during the 130 years of the study period, there were 200 anomalously heavy precipitation months (AHMs), which occurred in 106 years. Most of them were only recorded at either a single station or at two neighbouring stations, which would suggest that precipitation of this magnitude depends not just on circulation circumstances, but also on local factors. No statistical change was found in the long-term A H M occurrence pattern. There were two instances, where an A H M was recorded simultaneously at all 16 stations, in May 1940 and 2010, and they both contributed to catastrophic floods. The latter of the events involved both the highest absolute totals (exceeding 500 mm) and the highest relative totals (i.e. the percentage of the long-term average close to 500%). The A H Ms tended to coincide with cyclonic circulation. Between October and March, this was the western cyclonic circulation ( Wc ), while for the remaining part of the year it was cyclonic trough (Bc)

Zmienność czasowa najwyższych miesięcznych sum opadów atmosferycznych w Polskich Karpatach Zachodnich (1951-2005)

W artykule zbadano wieloletni i roczny przebieg najwyższych miesięcznych sum opadów atmosferycznych w Polskich Karpatach Zachodnich na podstawie danych z 6 stacji: Nowy Sącz, Sanok, Bielsko-Biała, Maków Podhalański, Krynica i Zakopane z okresu 1951–2005 oraz wyznaczono ich wartości prawdopodobne. Wykazano, że najwyższe miesięczne sumy opadów mogą występować w ciągu całego roku, z największą częstością w miesiącach letnich. Nie stwierdzono istotnych statystycznie trendów zmian wieloletnich, a jedynie krótkookresowe fluktuacje

Application of 2D RST method for spatial distribution of annual precipitation determination in the Upper Vistula Basin

Spatial distribution of annual precipitation is important element of engineering hydrology. To prepare precipitation maps for larger areas, proper methods of spatial interpolation and long-term precipitation records are needed. For analysed Upper Vistula Basin, 403 such representative stations with records for years 1952-1981 have been chosen and verifi ed. Regularized Spline with Tension method of interpolation have been selected (2D version) to intepolate spatial distribution of annual precipitation in Soła watershed, and cross-validation method for results verifi cation

Periods without precipitation and with low precipitation in the Polish Carpathians in the years of 1984-2013

W pracy zbadano ciągi dni bez opadów oraz ze słabymi opadami atmosferycznymi z uwzględnieniem ich uwarunkowań cyrkulacyjnych. Dokonano również oceny częstości okresów posuchy atmosferycznej, które wyznaczone zostały metodą opracowaną przez Koźmińskiego (1986) oraz Konopko (1988), na podstawie wartości dobowych sum opadów z okresu 30-letniego 1984–2013 z 49 stacji pomiarowych położonych w polskich Karpatach. Uwzględnione dobowe sumy opadów atmosferycznych z okresu badań uzyskano z IMGW-PIB. Na badanym obszarze największa średnia liczba dni w roku bez opadów atmosferycznych miała miejsce w Świdniku-Tęgoborzu – 214 dni, a najmniejsza w Wiśle-Malince – 157. Najwięcej sekwencji bezopadowych dostrzeżono w pojedynczych dobach – we wszystkich stacjach pomiarowych ich liczba w trzydziestoleciu przekroczyła 550. Najdłuższy, 40-dniowy, okres bez-opadowy wystąpił w Ciśnie (29 IV–7 VI 1991) oraz w Szczyrku (21 X–29 XI 2011). W każdym roku, oceniając według metody Koźmińskiego (1986), na obszarze polskich Karpat średnio wystąpiły 2–3 posuchy atmosferyczne trwające 11–15 dni, 1–2 posuchy trwające 16–20 dni. Natomiast średnio 1 posucha w roku o czasie trwania powyżej 20 dni wystąpiła we wszystkich stacjach pomiarowych, z wyjątkiem stacji położonych w zlew-ni Małej Wisły i Soły. W analizowanym wieloleciu nie stwierdzono istotnych zmian liczby posuch niezależnie od czasu ich trwania. Najdłuższy okres bez opadów atmosferycznych lub ze słabymi opadami w okresie badań wystąpił w typach cyrkulacji antycyklonalnej – południowej (Sa), zachodniej (Wa) oraz kli-nie antycyklonalnym (Ka).This paper describes the sequences of days without any precipitation as well as those with small precipitation consid-ering their circulation determinants. The frequency of the dry spells identified with the method developed by Koźmiński (1986) and Konopko (1988) was also examined. The sequenc-es of days without any precipitation or with small precipitation were determined based on the daily sums of precipitation over 30 years, i.e. within the years 1984–2013 from 49 measuring stations located in Polish Carpathian Mountains. The data of daily precipitation sums were obtained from the IMGW-PIB. In the study area the highest average number of days without any precipitation – over 200 days was in Świdnik-Tęgoborze– 214 days, and the lowest in Wisła-Malinka – 157 days. Most of the cases without precipitation were as single days and the number of these days in all measuring stations during analysing period exceeded 550 days. The longest, forty-day, period of sequential days without precipitation was noticed in Cisna (29 IV–7 VI 1991) and in Szczyrk (21 X–29 XI 2011). In every year according to Koźmiński’s method (1986) in the area of Polish Carpathian Mountains there occurred on aver-age 2–3 dry spells lasting 11–15 days, 1–2 dry spells lasting 16–20 days. On the other hand, on average 1 dry spell last-ing over 20 days took place in all measuring stations, except in the measuring stations located in the catchment of Small Vistula and Sola River. In analysing period it was not certi-fied the significant changes number of dry spells independently of their duration. In the study area, the longest period without precipitation or low precipitation was regarded to anticyclonic circulation types – southern (Sa), western (Wa) as well as the anticyclonic wedge (Ka) type

Niedobory opadów atmosferycznych w okresie wegetacyjnym w zlewni Małej Wisły (1984–2013)

Zbadano ciągi dni bez opadów, które wyznaczono na podstawie wartości dobowych opadów atmosferycznych z 12 stacji pomiarowych położonych w zlewni Małej Wisły. Dokonano również oceny niedoborów miesięcznych opadów atmosferycznych, wykorzystując wskaźnik względny opadu (RPI) oraz wskaźnik standaryzowanego opadu (SPI). Uwzględnione dane, sumy dobowe opadów atmosferycznych z lat 1984–2013 pochodzą z IMGW-PIB. Wykazano, że średnia liczba dni w roku bez opadów na badanym obszarze wyniosła od 157 w Wiśle Malince do 195 dni w Warszowicach, a w okresie wegetacyjnym od 85 dni w Wiśle Malince, 89 dni w Istebnej-Stecówce i Wiśle Głębcach do 99 dni w Tychach oraz 102 dni w Warszowicach. W okresie badanego 30-lecia najwięcej posuch wystąpiło w latach: 1992, 1994, 1999, 2005. W przypadku liczby miesięcy z opadami poniżej wartości średniej wieloletniej – najmniej wystąpiło w Górkach Wielkich i w Warszowicach – 59, a najwięcej – 71 w Ustroniu Równicy. Liczba zaś miesięcy z niedoborami opadów o różnym nasileniu, wyznaczona na podstawie wartości SPI, waha się od 48 w Warszowicach i Wiśle Głębcach do 55 w Mazańcowicach. Najsilniejsza susza meteorologiczna okresu wegetacyjnego wystąpiła w kwietniu 2009 roku na całym obszarze objętym badaniami

Maximum daily precipitation in Kraków in the period 1863-2015

Maximum daily precipitation is one of the most important hydrometeorological characteristics. Its study in densely developed urban areas can have practical, as well as theoretical, significance, especially for environmental engineering. Indeed, this is where intensive rainfall events can result in drainage problems leading to waterlogging, flooding and potentially to large-scale infrastructural losses. The objective of this study is to determine the annual and multi-annual variability in maximum daily precipitation totals and its determinants in the atmospheric circulation. The two main sources used for the study include records of maximum precipitation spanning the period from 1863 to 2015 in Krakow and the catalogue of atmospheric circulation types over southern Poland by T. Niedźwiedź. Maximum annual and monthly daily precipitation totals were included. The study determined their share of the overall monthly and annual totals. The highest maximum daily precipitation total recorded during the study period was 99 mm (9 September 1963), which approximately corresponds to the exceedance probability of 0.5%. It contributed 58.9% to the monthly precipitation total and 12.7 per cent to the annual total in that year. Maximum daily precipitation was recorded between March and November, and is most frequent in July at 27%. As many as 98.7% of the maximum precipitation totals belonged to the "very high" category. The difference between the highest and lowest maximum precipitation totals was 82 mm. No significant trend was identified in the occurrence of maximum totals over the study period. Maximum totals concentrated predominantly on days with cyclonic circulation types, at 87%, including 31% per cent which occurred in the cyclonic trough