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

The frequency of occurrence of Subarachnoid Hemorrhage (SAH) in the province of Łódź in the period 1992-1995 in relation to selected weather types

Opracowanie jest próbą określenia związku między warunkami atmosferycznymi a częstością występowania krwotoków podpajęczynówkowych (SAH) na terenie województwa łódzkiego w latach 1992-1995. Analizę przeprowadzono w świetle dwóch typologii pogody, uwzględniających następujące elementy meteorologiczne: średnią dobową amplitudę temperatury powietrza i ciśnienia atmosferycznego, prędkość wiatru, wilgotność względną, zachmurzenie. W opracowaniu zweryfikowano również hipotezę o podwyższonej liczbie SAH w następstwie dobowej zmiany ciśnienia atmosferycznego i charakteru tendencji ciśnienia. Analiza dostępnych danych nie wykazała statystycznych związków między liczbą SAH a warunkami atmosferycznymi.The purpose of the present study is to determine whether fluctuation of atmospheric conditions and types of the weather are related to occurrence of subarachnoid hemorrhage (SAH). The data on patients with SAH were collected by Neurosurgery Clinics and Neurology Departments in province of Łódź in the period 1992-1995. During analysed period 585 patients with SAH were treated (on average 12 per month). Two weather typologies based on daily temperature amplitude, wind speed, air pressure, relative humidity, cloudiness were proposed for the present study. Relationship between frequency of SAH and weather types was assessed using chi-square test. No statistical significant relations were detected. It can not be proof that weather does not influent on SAH occurrence but investigation with longer data series are necessary to separate adverse influences of selected meteorological parameters

Preliminary results of measurements of absolute short wave radiation and UV radiation in Łódź

Celem opracowania jest prezentacja pierwszej serii pOIn1arow (styczeń-lipiec 1997 r.) całkowitego promieniowania UV w Łodzi, ze szczególnym uwzględnieniem dobowego biegu promieniowania w różnych warunkach meteorologicznych. Kształt krzywych obrazujących dzienny przebieg wartości natężenia promieniowania całkowitego - le> promieniowania UV - I•• oraz stosunku I,.fIe (w %) zdeterminowany jest głównie czynnikami astronomicznymi, przezroczystością atmosfery, stopniem zachmurzenia nieba. Najwyższa średniodobowa wartość le wystąpiła podczas bezchmurnej pogody w czerwcu (30 czerwca 1997 r.) - 487 W/m2, a I,. = 35,5 W/m2• W dniach o dużym zachmurzeniu wartości ulegają zmniejszeniu (np. 19 lipca 1997 r. le =49 W/m2, a I•• = 3,2 W/m2). W bezchmurne dni stosunek I,.fIe wynosi średnio 3--4%, podczas gdy w dni pochmurne udział nadfioletu wzrasta powyżej 6%.The paper presents the preliminary results of the measurements of DV radiation intensity,I uv' and the total short wave radiation,le'(in W/m 2)in Łódź. The data were collected in the city centre for the period January-July 1997. The aim of the work is comparison of daily courses of IuY'le andthe ratio Iuvfle (in%) during various weather conditions. The daily courses of Iw and le are similar, depending on sun position, cloudiness or air transparency. The radiation is higher during clear weather reaching maximum daily mean values on 30 June 1997 le=487W/mz and I uv= 35.5W/m2•\ During cloudy weather these values are lower(le= 49W/m2 and Iw = 3.2 W/m 2 on 19 July 1997). For fine weather the ratio Iuvfle has well marked daily course with average 3-4% where as cloudy conditions disturb this course and lead to the ratio even more than 6

Radon intercomparison tests – Katowice, 2016

At the beginning of the year 2016, the representatives of the Polish Radon Centre decided to organize profi ciency tests (PTs) for measurements of radon gas and radon decay products in the air, involving radon monitors and laboratory passive techniques. The Silesian Centre for Environmental Radioactivity of the Central Mining Institute (GIG), Katowice, became responsible for the organization of the PT exercises. The main reason to choose that location was the radon chamber in GIG with a volume of 17 m3, the biggest one in Poland. Accordingly, 13 participants from Poland plus one participant from Germany expressed their interest. The participants were invited to inform the organizers about what types of monitors and methods they would like to check during the tests. On this basis, the GIG team prepared the proposal for the schedule of exercises, such as the required level(s) of radon concentrations, the number and periods of tests, proposed potential alpha energy concentration (PAEC) levels and also the overall period of PT. The PT activity was performed between 6th and 17th June 2016. After assessment of the results, the agreement between radon monitors and other measurement methods was confi rmed. In the case of PAEC monitors and methods of measurements, the results of PT exercises were consistent and confi rmed the accuracy of the calibration procedures used by the participants. The results of the PAEC PTs will be published elsewhere; in this paper, only the results of radon intercomparison are described

Results of 1-year monitoring of air radon concentration in a detached house in Łódź with reference to meteorological conditions

W pracy dokonano analizy zmienności stężenia aktywności radonu (Rn-222) w powietrzu, rejestrowanego w trybie ciągłym, w domu jednorodzinnym w Łodzi, w okresie 356 dni, w latach 2014–2015. Tło meteorologiczne pomiarów Rn-222 stanowiły wartości temperatury powietrza w budynku i w warunkach zewnętrznych, sum godzinnych opadu atmosferycznego, ciśnienia atmosferycznego oraz typy cyrkulacji. Stwierdzono zmienność sezonową oraz dobową poziomu stężenia badanego radionuklidu w powietrzu uwarunkowaną sposobem użytkowania domu oraz czynnikami meteorologicznymi. Zamknięcie (nieużytkowanie) domu w lipcu 2014 roku spowodowało 5-krotny wzrost stężenia aktywności Rn-222 w stosunku do wartości średniej. Spadek temperatury powietrza w otoczeniu budynku wykazał słabą korel ację dodatnią, ze wzrostem stężenia aktywności Rn-222 w domu. Zmniejszenie poziomu stężenia aktywności Rn-222 w budynku obserwowano po intensywnych opadach. Ciśnienie atmosferyczne i typ cyrkulacji nie wykazywały wpływu na poziom rejestrowanego stężenia aktywności Rn-222.The aim of the study was to investigate the variability of air Rn-222 concentration in a single-family detached house in Łódź with reference to indoor-outdoor air temperature differences, precipitation, air pressure and type of atmospheric circulation. Experiments comprising continuous, simultaneously measurements of meteorological elements and air Rn-222 concentration using AlphaGUARD® PQ2000 PRO (ionization chamber, diffusion mode) in the period from 20 May 2014 to 10 May 2015. A slightly positive correlation between Rn-222 levels and indoor-outdoor air temperature has been shown but the relationship with air pressure was not confirmed. The analysis indicated that rainfall can be an important meteorological controlling factor of air Rn-222 levels in houses located in an area with shallow groundwater

Variability of radom (Rn-222) concentration in the near-ground air layer with reference to soil heat flux value

Celem opracowania jest znalezienie związku między stężeniem radonu (ρRn-222), rejestrowanym w powietrzu 2 m nad gruntem, i strumieniem ciepła glebowego (QG). Pomiary ρRn-222 wykonywano co 1 godz. za pomocą automatycznej komory jonizacyjnej Alpha GUARDR PQ2000 Pro. Synchronicznie do stężenia radonu w latach 2008-2010 mierzono QG za pomocą czujnika typu HFP01 Heat Flux Plate firmy Cambell Scientific Ltd. w centrum Łodzi oraz na stacji zamiejskiej Ciosny (teren rolniczy, 25 km na połnoc od Łodzi). Badane zmienne cechuje quasi-synchroniczny przebieg dobowy z maksimum w godzinach nocnych i minimum w godzinach popołudniowych. Związek ρRn-222 i QG opisano modelem funkcji eksponencjalnej. Na stacji Ciosny miesiące od III do XI cechują się bardzo wysokim stopniem dopasowania danych modelowanych do danych pomiarowych stężenia radonu w świetle indeksu zgodności Willmotta. Dla stacji w Łodzi uzyskano gorsze rezultaty, stosując model ρRn-222 w którym wykorzystuje się strumień ciepła glebowego.The aim of the study was to find the relationship between radon (Rn-222) concentration and soil heat flux. Atmospheric concentration of radon was measured continuously (in 60-min intervals) at a height of 2 m above the ground using AlphaGUARD® PQ2000PRO (ionization chamber) at urban (city center of Łódź) and rural (Ciosny, 25 km north of Łódź) site in the period 2008-2010. Simultaneously, soil heat flux (QG) was measured by means of HFP01 Heat Flux Plate, Campbell Scientific Ltd. The diurnal pattern of Rn-222 concentration was revealed with a maximum in the early morning and a minimum in the afternoon. In general, the diurnal variation of near-surface Rn-222 concentration varied approximately in phase with the soil heat flux. The exponential function model was used to estimate a daily course of radon concentration on the basis of soil heat flux values in particular months. The period from March to November was characterised by a good agreement between the observed and model-predicted Rn-222 concentration ("index of agreement" by Willmott was used to evaluate the model). Measured Rn-222 concentrations in the rural station Ciosny fitted better to model data than those from the urban station in the city center of Łódź

Meteorological factors of radon concentration in the near ground air layer in an urban and rural environment

Opracowanie poszerza wiedzę na temat czasowej zmienności stężenia radonu Rn-222 w powietrzu atmosferycznym na obszarze miasta i na terenie niezurbanizowanym oraz poszukiwania związku tej zmienności z lokalnymi i makroskalowymi warunkami meteorologicznymi. W pracy podjęto próbę oceny wpływu poszczególnych elementów meteorologicznych na kształtowanie dynamiki zawartości radonu w powietrzu. Ocenie poddano także rolę cyrkulacji atmosferycznej determinującej dwie składowe stężenia tego radionuklidu przy gruncie, tj. składową lokalną i składową będącą efektem transportu radonu do miejsc pomiaru. Ponadto celem badawczym była odpowiedź na pytanie, czy środowisko miejskie cechuje odmienna dynamika zmian stężenia radonu w powietrzu w porównaniu z rolniczymi terenami zamiejskimi.Udostępnienie publikacji Wydawnictwa Uniwersytetu Łódzkiego finansowane w ramach projektu „Doskonałość naukowa kluczem do doskonałości kształcenia”. Projekt realizowany jest ze środków Europejskiego Funduszu Społecznego w ramach Programu Operacyjnego Wiedza Edukacja Rozwój; nr umowy: POWER.03.05.00-00-Z092/17-00

Dry and wet periods in Łódź in XXth century

Artykuł powstał w wyniku prac badawczych prowadzonych w ramach Projektu Zamawianego MNiI (K091/P04/2004/11).The aim of this work is to present the results of total daily precipitation series, which had been registered in Łódź in 1904-2000. In the structure of daily precipitation conditions the days without falls (54.2%) and with falls of 0.1-4.9 mm (36.1%) were dominant. Total maximum daily precipitation changed perennially from 14.2 mm to 103.5 mm. The longest continuous peńods of dryness in Łódź lasted 45 days, whereas the longest periods of continuous falling lasted 31 days. It was observed that 40's and 50's were the years of the most frequent dry periods. Maximum length of continuous precipitation periods shortened from 30 days in 30's to 14 and 15 days in 80's and 90's. Looking for long lasting tendencies of the time changeability of precipitation characteristics by using non-parametric test by Mann-Kendall and non-parametric Sen's method, which is used for calculating regression coefficients in linear trends equations, shows lack of statistically significant tendencies. This happens in case of daily capacities and extreme total fall, as well as total annual number of days without and with falling being equal or bigger than 5 mm and ~ 10 mm. Positive trends, statistically significant on a level of 0.05 characterize dryness indices in February and April, while indices on a 0.01 level are characteristic for August

Cechy solarne klimatu Łodzi

The objective of the study was the characterization of solar regime of Łódź and the surroundings e.g. the daily, the annual, the long-term variability of sunshine duration and total and UV solar radiation, the structure of sunshine duration with a special consideration of sunless and very sunny days, the relationship between solar components of climate, the influences of clouds on solar radiation income to an active surfaces, etc. The experimental materials for the study constituted of the daily totals of actual and relative sunshine duration in the period 1951-2000, the daily sums of total solar radiation in the period 1991-2002, measured in the Łódź-Lublinek station (S-W part of the city), 5-year data series of 10-minutes averages of intensity (in Wm-2) of total (305-2800 nm) and UV (290-400 nm) solar radiation in the period 1997-2001, registered in the city center of Łódź. The long-term tendencies of sunshine duration were analyzed by means of linear regression method and sequential version of the non-parametric Mann-Kendall test. All months excluding March, June and September are distinguished by a growing tendency of actual and relative sunshine duration. The number of sunny hours increases in spring, summer and winter, and decreases in autumn. An increase of annual sunshine duration totals (3.5h/year) within the 50-year period was stated. Transformation of the annual course of sunshine duration within 50-year period was detected. The annual maximum of sunshine duration during the first 25-year period occurred in June and September. The second 25-year period was characterized by increase of the number of sunny hour in May and August and by decrease of sunshine duration in June and September. The time of registration of sunshine duration extended in the morning hours and before the Sun set as a consequences of low cloudiness negative trend. The structure of sunshine duration in Łódź was presented in 5 classes of possible sunshine duration (0 - sunless days, 0.1-25% - cloudy days, 25.1-50% - moderately sunny days, 50.1-75% - sunny days, > 75% - very sunny days). Only very sunny days were distinguished by a positive annual totals trend, on average 4 days per 10 years. The tendencies of sunshine duration recorded in Łódź within fifty last years are representative for Poland and result from the macroscale factor (atmospheric circulation) not only from the influences of local (anthropogenic) conditions. The regular fluctuations in the time series of sunshine duration and solar radiation were investigated by Blackman-Tukey classical spectral analysis method. The weak periodicity (statistical insignificance) amounted 8.3, 2.5, 2.8, 3.8 years and the significance short oscillations amounted 182.5, 91.2, 73 days were detected in sunshine duration time series. The total and UV solar radiation time series were characterized by 182.5, 121.7, 73 days significance periodicities. The values of transmission coefficient of total and UV solar radiation were investigated. The daily values of transmission coefficient varied from 25% (total radiation) and 14% (UV) in December to 50% (total radiation) and 26% (UV) in May.Zadanie pt. „Digitalizacja i udostępnienie w Cyfrowym Repozytorium Uniwersytetu Łódzkiego kolekcji czasopism naukowych wydawanych przez Uniwersytet Łódzki” nr 885/P-DUN/2014 dofinansowane zostało ze środków MNiSW w ramach działalności upowszechniającej naukę