Urban vegetation effect on thermic and humidity conditions

Researches of urban verdure effect on thermic and humidity conditions, carried out for 1971-75 by Warsaw University, proved that the influence occured very distinctly in summer months. The influence of grounds with vegetation on air temperature and humidity occurs for areas at least of 3000 m² Then it can be sensible 1,5 m high over the ground surface. The verdure terrains cause decreasing of the temperature especially in the evening and the night, as well as increasing of the air humidity (humidity pressure and relative humidity). The temperature is decreased mostly by a presence of trees, and the humidity is increased especially by abundant grass cover and a protection from winds. The lawns are favourable to evening temperature inversion. The conclusion from the obtained results in that a remissive effect of lawns and parks on the climate is the strongest when the verdure is differentiated as grass and shrubbery and trees

Extreme Maximum or the Arrogance of Ignorance

W artykule autorka omawia powszechnie popełniane błędy językowe w tekstach głównie z zakresu klimatologii. Błędy te wynikają z niedokładnej znajomości słów – nie tylko obcego pochodzenia, ale i słów polskich, z braku wrażliwości językowej, a także z nieznajomości gramatyki. Artykuł jest zilustrowany licznymi przykładami zaczerpniętymi z prac naukowych i innych. Autorka zwraca uwagę na konieczność pisania w sposób poprawny i zrozumiały, co jest wyrazem szacunku dla czytelnika i zarazem dbałości o własny wizerunek.The author discusses common language problems encountered in scientific papers written in Polish and focuses specifically on climatology. The problems involve the effects of imprecise usage of terminology, both Polish and foreign, insufficient sensitivity to aspects of language, and of grammatical inadequacies. The paper is illustrated by numerous examples taken from scientific and non-scientific texts. It is advocated that authors should use a correct and lucid written style to convey respect to the reader and to build up their own image

Monthly thermal and precipitation conditions and their dependence upon atmospheric circulation

On the basis of two time sequences (for 1871-1970 and 1951-1994) of average monthly temperatures and monthly precipitation sums in Warsaw the nature of relation between these two quantities was analysed. Months were divided into three classes of equal cardinality: the cold, the normal and the warm ones and the dry, the normal and the rainy ones. It was stated that between November and February the cold months have precipitation at the normal level or below, while warm months have precipitation at the normal level or above. From May to September the situation is reversed: the cold months are more often rainy, while wann ones - dry. The months of March, April and October are of transitory character, since in the case of these months the cold dry and rainy as well as warm dry and rainy months occur with equal probability (Table 1 ). In the second part of the paper the frequency and the nature of anomalous months were considered, with the normal months understood as such during which temperature and precipitation are contained in the interval [multiannual average - standard deviation; multiannual average + standard deviation]. It was stated that during the cooler part of the year greater negative than positive deviations of temperature occur, and that frequently cold and very cold months are dry, while during summer there are bigger positive deviations and the warm as well as very warm months are often dry, and never rain (Table 2). The temperature and the precipitation in the months with extreme thermal and/or precipitation features were put together (Table 3) and the nature of atmospheric circulation in the anomalus months was analysed. It turned out that in winter (from November to February) the abnormally cold months feature the domination of anticyclonic eastern and northern circulation, while the abnormally warm months - domination of cyclonic western and south-western circulation. In spring (from March to May) cold months feature domination of the circulation types from the northern sector, both cyclonic and anticyclonic ones, while warm months - from the southern sector. In summer (from June to September) during the cold months cyclonic circulation from the northern sector, and especially from the north-western sector dominates, while during the warm months - anticyclonic circulation from the southern and eastern sectors. During cold October the anticyclonic circulation from the North or the East appears most often, while during warm October - cyclonic or anticyclonic circulation from the southern or south-western sector. During the whole year the dry months feature very high frequency of the anticyclonic circulation types ( especially the eastern ones), while the rainy months - the cyclonic types (Table 4)

Wplyw zabudowy miejskiej na zmiennosc temperatury z dnia na dzien

The purpose of the study is to obtain the answer to the question weather urban development has influence - and if so - on interdiurnal changes of air temperature. The answer is of considerable importance because many climatological stations, from which data for temperature changes studies comes from, are placed in towns. Data taken for the study were the daily values of mean daily temperature, maximum and minimum temperature for the 5 year period 1961-1965 from 5 climatological stations in Warsaw. The analyais of mean monthly values of temperature changes, frequency of changes of different size as well as course of temperature in chosen months has proved, that urban development most strongly influences interdiurnal changes of the minimal temperature, decreasing its average value and the frequency of appearance of extremely high changes. Such influence is most strongly observed in winter, when on the turn of spring and summer in the town's center interdiurnal changes of the maximum temperature may be a little higher. The influence of urban development on air temperature changes turned out to be dependent on the amount of cloudiness and wind velocity (bigger influence when smaller cloudiness and low wind velocity), and also from the direction of wind (larger changes on the windward side of the city)

How the Size of the Weather Station Sample Influences the Number of Exceptionally Cold and Exceptionally Warm Months Identified in Europe (1951-2010)

W artykule przedstawiono dyskusję wyników badań uzyskanych na podstawie różnego zagęszczenia stacji meteorologicznych wykorzystanych do charakterystyki niezwykle zimnych (NZ) i niezwykle ciepłych (NC) miesięcy zimowych i letnich w Europie w 60-leciu 1951-2010. Podstawę analizy porównawczej stanowiła liczba miesięcy NZ i NC, jak i obszary, na których poszczególne anomalne miesiące wystąpiły wyłonionych na podstawie 210 i 60 stacji, wybranych spośród tych 210, tzn. w wariancie „210” i „60” . Kryterium wyłonienia miesięcy NZ i NC miesięcy była wartość średniej temperatury powietrza różniąca się od średniej wieloletniej na danej stacji przynajmniej o 2 odchylenia standardowe. Uzyskane wyniki pokazały, że zagęszczenie sieci stacji (wariant „210”) umożliwiło, zgodnie z przyjętą hipotezą badawczą, rozpoznanie większej liczby miesięcy anomalnych pod względem termicznym, zwłaszcza występujących na pojedynczych stacjach. Badania zasięgu terytorialnego występowania anomalii podczas miesięcy NZ i NC pokazały, że wyniki dotyczące miesięcy, które wystąpiły na przynajmniej 5% stacji w obydwu wariantach nie różnią się zasadniczo od tych opartych na gęstszej sieci stacji. Te drugie stanowią ich uszczegółowienie.This research topic arose following a long line of papers published by the authors on exceptionally cold and warm months (ECMs, EWMs) or seasons. The seasonal approach was covered earlier (e.g. Kossowska-Cezak, Twardosz, 2015; Kossowska-Cezak et al., 2016; Twardosz, Kossowska-Cezak, 2015, 2016; Twardosz et al., 2016) and included records from 60 stations selected out of a pool of 210 stations. This was followed by publication of a volume, which focused on months and took data from all of these 210 stations over the period 1951-2010 (Fig. 1). The different sample size has had the authors ask the question how it might have influenced the number of ECMs and EWMs and the areas affected with these phenomena. The months were defined to fall into the exceptional category if their average air temperature differed from the long-term average at a given station by two standard deviations or more. The comparative analysis covered the number of ECMs and EWMs identified in Europe during the 60-year study period (Tab. 1), the areas of occurrence of some of these months that were identified using weather station networks of different densities (Fig. 2-4), and those ECMs and EWMs that differed in the number of stations included in the two approaches by a large margin (Fig. 5). The results showed that by increasing the station network density (210) the number of anomalous months identified became higher, especially at single stations. In contrast, the sample size did not have much of an impact on the territorial reach of each ECM or EWM and the denser station network only increased the detail of each coverage

Wojciech Jastrzębowski as a Climatologist

Autorzy przypominają postać Wojciecha Jastrzębowskiego (1799-1882), botanika, rolnika i leśnika, uczonego i nauczyciela. W. Jastrzębowski interesował się też meteorologią i klimatologią. Jest on autorem pierwszego opracowania klimatu Warszawy opartego na wieloletnich (1779-1828) danych pomiarowych, zatytułowanego Karta Meteorograficzna stolicy Królestwa Polskiego (1828). W. Jastrzębowski opublikował też dane z Warszawy z lat 1779-1828 i powtórne wydanie Karty... (1846).The authors wish to remind us about the figure of Wojciech Jastrzębowski (1799-1882), a botanist, farmer, forester, scholar and teacher. Wojciech Jastrzębowski is also known for his interest in meteorology and climatology. He wrote the first study of the climate of Warsaw (Karta Meteorograficzna Stolicy Królestwa Polskiego (1828), which he based on long-term (1799-1828) measurement records and which he illustrated with an annual chart depicting a range of weather elements.He went on to publish weather data from Warsaw spanning 1779-1828 and a second edition of his Karta… (1846)