Robert Twardosz

Prof. Dr. Robert Twardosz

orcid

Research Focus & Metrics

Academic Career Length

26Years (2001-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
20 September 2021 in Pure and Applied Geophysics
Verified
Journal Article
Open access
PDF file
RTRobert Twardosz
Robert Twardosz
AWAdam Walanus
Adam Walanus
IGIzabela Guzik
Izabela Guzik
Contemporary climate warming is a key problem faced not only by scientists, but also all by humanity because, as is shown by the experience of recent years, it has multiple environmental, economic and biometeorological implications. In this paper, the authors identify the magnitude of annual and seasonal temperature changes in Europe and its immediate surroundings on the basis of data from 210 weather stations from 1951 to 2020. An analysis of temperatures in the 70-year period shows that air temperature has continued to grow linearly in Europe since 1985. The rate of temperature rise in three seasons of the year, namely winter, spring and summer, does not differ greatly. The highest growth over the 1985–2020 timespan was recorded in spring and the lowest in autumn—0.061 °C/year and 0.045 °C/year, respectively. In winter, the rise in temperature should be considered the least steady, as opposed to the summer when it displays the greatest stability. Overall, the warming intensifies towards the north-east of the continent. Such a strong gradient of change is especially perceivable in winter and spring, and is also marked in autumn. The opposite is true in summer, when it increases towards the south and south-west.

24 February 2009 in Theoretical and Applied Climatology
Verified
Journal Article
Closed access
PDF file
TNTadeusz Niedźwiedź
Tadeusz Niedźwiedź
RTRobert Twardosz
Robert Twardosz
AWA. Walanus
A. Walanus

6 September 2012 in Theoretical and Applied Climatology
Verified
Journal Article
Open access
PDF file
RTRobert Twardosz
Robert Twardosz
UKUrszula Kossowska-Cezak
Urszula Kossowska-Cezak
The paper focuses on exceptionally hot summers (EHS) as a manifestation of contemporary climate warming. The study identifies EHS occurrences in Central and Eastern Europe and describes the characteristic features of the region’s thermal conditions. Average air temperatures in June, July and August were considered, as well as the number of days with maximum temperatures exceeding 25, 30 and 35 °C, and with a minimum temperature greater than >20 °C, as recorded at 59 weather stations in 1951–2010. Extremely hot summers are defined as having an average temperature equal to or greater than the long-term average plus 2 SD. A calendar of EHSs was compiled and their spatial extent identified. The region experienced 12 EHSs, which occurred in a given year at 5 % or more stations (1972, 1981, 1988, 1992, 1997, 1998, 1999, 2002, 2003, 2006, 2007 and 2010). The EHS frequency of occurrence was found to be clearly on an increase. Indeed, only one EHS occurred during the first 30 years, but these occurred five times during the last 10 years of the study period. Their geographical extent varied both in terms of location and size. EHSs were observed at 57 out of the total of 59 weather stations in the study (the exceptions were Pecora and Cluj). The average air temperature of EHSs tended to exceed the relevant long-term average by 2–4 °C. The summer of 2010 was among the hottest (temperature anomaly 5.5–6 °C) and spatially largest.

21 September 2010 in Theoretical and Applied Climatology
Verified
Journal Article
Open access
PDF file
RTRobert Twardosz
Robert Twardosz
TNTadeusz Niedźwiedź
Tadeusz Niedźwiedź
EŁEwa Łupikasza
Ewa Łupikasza
The paper discusses the impact of atmospheric circulation on the occurrence of various types of precipitation. A 146-year-long precipitation record from Kraków spanning the period 1863–2008 was used alongside a calendar prepared by Niedźwiedź (1981, 2009) describing circulation types covering the period 1873–2008 and air masses and atmospheric fronts covering the period 1951–2008 in southern Poland. The influence of atmospheric circulation on precipitation was measured using the frequency, conditional probability and average daily totals of precipitation. Circulation types, air masses and atmospheric fronts exerted influences on precipitation as a result of the seasonal variations of the thermal and moisture properties of air masses. The impact is best expressed by circulation types as these combine the aspect of cyclonicity/anticyclonicity with that of the direction of air advection, the two elements which determine the physical properties of the air. On average, liquid precipitation prevailed in all circulation types, except the Ea type in which snowfall dominated over liquid precipitation. Depending on the season, one of the three types of circulation, Wa, Wc and Bc, were shown to coincide with the greatest amount of liquid and thunderstorm precipitation. There was no single dominant circulation type for mixed precipitation or snowfall. In summer, the circulation types Nc, NEc, Cc and Bc were the most favourable to liquid and thunderstorm precipitation in terms of both probability and totals. In winter, snowfall was the most favoured by the Ec type. Frontal precipitation was twice as likely to occur as air mass precipitation, with the exception of snowfall which was predominantly an air mass type of precipitation in terms of probability, but its greatest totals were recorded on atmospheric fronts.

26 October 2021 in International Journal of Biometeorology
Verified
Journal Article
Open access
PDF file
KBKrzysztof Błażejczyk
Krzysztof Błażejczyk
RTRobert Twardosz
Robert Twardosz
PWPiotr Wałach
Piotr Wałach
KCKaja Czarnecka
Kaja Czarnecka
ABAnna Błażejczyk
Anna Błażejczyk
The occurrence of long-lasting severe heat stress, such as in July–August 2003, July 2010, or in April–May 2018 has been one of the biggest meteorological threats in Europe in recent years. The paper focuses on the biometeorological and mortality effects of the hot June that was observed in Central Europe in 2019. The basis of the study was hourly and daily Universal Thermal Climate Index (UTCI) values at meteorological stations in Poland for June 2019. The average monthly air temperature and UTCI values from 1951 to 2018 were analysed as background. Grosswetterlagen calendar of atmospheric circulation was used to assess synoptic conditions of heat wave. Several heat strain measures were applied : net heat storage (S), modelled heart rate (HR), sultriness (HSI), and UTCI index. Actual total mortality (TM) and modelled strong heat-related mortality (SHRM) were taken as indicators of biometeorological consequences of the hot June in 2019. The results indicate that prolonged persistence of unusually warm weather in June 2019 was determined by the synoptic conditions occurring over the European region and causing advection of tropical air. They led to the emergence of heat waves causing 10% increase in TM and 5 times bigger SHRM then in preceding 10 years. Such increase in SHRM was an effect of overheating and overload of circulatory system of human organism.

30 March 2001 in International Journal of Climatology
Verified
Journal Article
Open access
PDF file
RTRobert Twardosz
Robert Twardosz
TNTadeusz Niedźwiedź
Tadeusz Niedźwiedź
The impact of the synoptic situations on the occurrence of precipitation in Kraków is analysed. Daily records of precipitation from the period 1873–1999 were used, as well as the calendar of synoptic situations by T. Niedźwiedź. The study presents annual and long‐term variations of daily precipitation, frequency of the synoptic situations, and frequency of precipitation for particular situations. For the 21 types of synoptic situations, the following characteristics were defined: average daily precipitation and its effectiveness ratio, maximum precipitation and the probability of occurrence of days with or without precipitation. Most precipitation occurs during the advection of air masses from the west and during the cyclonic trough, which is related to high frequency of occurrence of such situations. From among 21 synoptic situations, the following ones are the most favourable for the development of abundant precipitation: northeastern cyclonic situation (NEc), north cyclonic situation (Nc), cyclonic trough (Bc) and centre of low pressure (Cc). Copyright © 2001 Royal Meteorological Society