Variability of weather extremes in Poland in the period 1951-2006

Ponencia presentada en: VI Congreso Internacional de la Asociación Española de Climatología celebrado en Tarragona del 8 al 11 de octubre de 2008.[ES]Series de indices de temperatura y precipitación extremas en el periodo 1951-2006 se calcularon a partir de datos de precipitación diaria y temperatura máxima y mínima en 21 estaciones en Polonia. dado que la distribución de indices de extremos es en general bastante distinta de la normal, en particular para indices que expresan ocurrencias diarias, los estimadores de tendencias mas usuales no son robustos en este caso. Se utilizaron el test tau de Kendall y el estimador de tendencias de Sen y sus resultados fueron comparados con los obtenidos con métodos mas tradicionales.[EN]Daily precipitation totals and daily minimum and maximum temperatures from 21 Polish stations were used to calculate records of indices of temperature and precipitation extremes in the period 1951-2006. Because the distributions of extreme indices are generally far from normal, especially for indices defined as day counts, the popular trend estimators like linear trend calculated by the least mean squares method are not robust. The Kendall tau test and Sen's trend estimators were used and their results were compared with those obtained by more traditional methods.The work was supported by the Polish Ministry of Education and Science under the Grant PBZ-KBN-086/PO4/2003

Comparison of temperature indices for three IPCC SRES scenarios based on RegCM simulations for Poland in 2011–2030 period

The regional climate model RegCM3 is used to investigate potential future changes of temperature indices in Poland for the period 2011–2030. The model is forced by ECHAM5/MPI-OM GCM data from World Data Centre (WDCC) database for the 1971–1990 reference period and 2011–2030 projection period under SRES B1, A1B and A2 emission scenarios. Model output statistics methods are used to transform simulated minimum and maximum temperature data into realistic data. Selected indices of temperature extremes and their differences between the scenario simulations and the reference were calculated, for all scenarios, for the entire period and for each season. Results show a mean yearly increase in the number of summer and hot days and a decrease in the number of frost and ice days. Highest decline in the number of frost and ice days in autumn and an increase in spring is noticed. An highest increase in the number of summer and hot days is seen in summer. Future projections of these indices are relevant for studies on climate change impact in agriculture, tourism, health, transportation, road and building infrastructure.This work was carried out as part of the project KLIMAT "Impact of climate change on the society, the environment and the economy (changes, effects and ways of limiting them, conclusions for science and engineering practice and economic planning)". No POIG.01.03.01- 14-011/08 in frames of the Operational Programme Innovative Economy, co-financed by the European Regional Development Fund. Authors thank anonymous reviewers for valuable comments

Opći pregled mogućeg utjecaja ekstremnih promjena temperature na društvo i gospodarstvo u Poljskoj u 21. stoljeću

This work gives an overview on how the projected changes in the extremes in Poland might impact human health and economy. For that purpose, statisti-cally corrected data from 7 regional climate models were used. A significant increase of extreme hot events (i.e. heat waves, tropical nights) is projected for Central and Southern Poland for the end of the 21st century which might seri-ously affect a society living in large urban areas. Less extreme cold events im-prove thermal comfort in winter. The negative impact of the warming will affect energy systems with higher demand for electricity in summer and agriculture: an earlier beginning of the growing season and flower blooming will enhance the risk of frost damages in spring, whereas excessive heat will reduce yields in summer. Polish tourism should benefit from higher thermal comfort (except for hot July and August in the far future and warming in the winter season bring-ing snow cover depletion in the near future).Ovaj rad daje pregled kako projicirane promjene ekstrema u Poljskoj mogu utjecati na ljudsko zdravlje i njezino gospodarstvo. U tu svrhu korišteni su statistički korigirani podaci iz 7 regionalnih klimatskih modela. Za srednju i južnu Poljsku predviđa se za kraj 21. stoljeća značajan porast ekstremnih vrućih događaja (tj. toplinskih valova, tropskih noći), što bi moglo ozbiljno utjecati na društvo koje živi u velikim urbanim područjima. Manje ekstremni hladni događaji poboljšavaju toplinsku ugodnost zimi. Negativni utjecaj zagrijavanja utjecat će na energetske sustave s većom potražnjom električne energije ljeti, a u poljoprivredi: raniji početak vegetacijske sezone i cvjetanje cvijeća povećat će rizik od oštećenja od mraza u rano proljeće, dok će pretjerana vrućina smanjiti prinose ljeti. Poljskom turizmu trebala bi pogodovati veća toplinska ugodnost (osim vrućeg srpnja i kolovoza u dalekoj budućnosti te zagrijavanja tijekom zimske sezone u bliskoj budućnosti, što će dovesti do smanjenja snježnog pokrivača)

Opady w Łodzi w okresie 1931-1995

W pracy wykorzystano miesięczne sumy opadu ze stacji Łódź-Lublinek z okresu 1931-1995. Przedstawiono podstawowe charakterystyki statystycme miesięcznych, sezonowych i rocznych sum opadu: średnią, odchylenie standardowe, wartości ekstremalne, asymetrię, współczynnik zmienności oraz rozkłady częstości miesięcmych sum opadu. Analizowano związki między wartościami miesięcznych sum opadu a indeksem NAO i częstościami wybranych klas cyrkulacji.Monthly precipitation totals from Lódź-Lublinek meteorological station from the period 1931-1995 have been used. Basic statistical features of monthly, seasonal and annual totals such as mean, standard deviation, extreme values, assymetry and coefficient of variability were presented together with frequency distributions of monthly totals. Relations of monthly totals to NAO index and frequencies of selected circulation types were analysed

Singularities of the urban climate of Łódź, Central Poland

Published in: Natural environment of Poland and its protection in Łódź University Geographical Research, edited by E. Kobojek and T.MarszałThe results presented in the work show the selected features of local climate modification caused by urbanisation in Łódź, Central Poland. The city structure is similar to many other mid-European towns, but the influences of urbanisation on local climate are not affected here by other factors. Thus, the outcomes of presented investigations can be generalised for many cities of the region. The findings about the urban heat island are similar to those of other cities and they confirm the general rules about the UHI phenomenon, its spatial distribution and temporal variations (see Arnfield 2003 for a comprehensive review). Similarly, the influence of the city on incoming shortwave radiation in Łódź simply quantify well established relations. More unique are the studies on the albedo and the influence of surface geometry on the absorption of radiation. The influence of the town on humidity is more disputable. On the average, our data confirm the findings on the urban-rural contrasts of these elements, but they also show that unlike the UHI evolution, the diurnal course of humidity differences can take different form even in favourable weather conditions. The measurements of turbulent fluxes of sensible and latent heat, carbon dioxide and methane are unique in Poland and one of the few in Europe; thus they just provide new data and extend our understanding of poorly known processes. At the present stage, it is hard to evaluate if these result are case-specific or more general. The comparison with other cities is problematic because of a small number of similar works – there are several concerning urban energy balance, very few on carbon dioxide flux, and almost none about the flux of methane

Ekstremalne warunki opadowe w Łodzi w okresie 1931-1995

W opracowaniu analizowano szereg dobowych sum opadu z Łodzi z okresu 1931-1995. Przedstawiono roczny bieg częstości występowania dni bez opadu i z opadem w poszczególnych przedziałach wartości. Stwierdzono, że pojawienie się opadu zależy w większym stopniu od charakteru cyrkulacji niż od kierunku napływu mas. Badano długoletnią zmienność częstości dni bez opadu, dni z sumą opadu powyżej 10 mm i największej dobowej sumy opadu w roku. Pokazano, że najwyższe dobowe sumy opadu pojawiają się w dniach o cyrkulacji EoRecord of daily precipitation totals from Łódź from the period 1931-1995 has been analysed. The annual courses of frequencies of days without precipitation and with precipitation in particular ranges were presented. It was shown that occurrence of precipitation is stronger related to the character of circulation than to direction of air mass advection. Long-term variability of frequencies of days without precipitation, days with totals exceeding 10 mm/day and long-term variability of the highest daily total during the year were analysed. It was shown that the highest daily totals occur in day with circulation of type Eo

Recent Change-Atmosphere

Non peer reviewe

How reliable are selected methods of projections of future thermal conditions? A case from Poland

The aim of the paper was to assess the robustness of four bias correction techniques: simple bias correction, distribution based bias correction, delta change and distribution based delta change. Data from nine RCM simulations of CORDEX project and 41 Polish weather stations were used. The methods were calibrated in the period 1971–1985 and evaluated in 1991–2005. The improvement in mean, 10th and 90th percentiles was shown, without significant differences among methods. For 1st and 99th percentiles the improvement was generally weaker and simple methods seem to be more robust than the distribution based ones. Strong differences between individual models were found, so the use of model ensemble is recommended