Air temperature changes in Toruń (central Poland) from 1871 to 2010

Abstract

The article presents a detailed analysis of changes in air temperature in Toruń in the period 1871-2010 on the basis of homogenised monthly, seasonal and annual air temperature series which have been newly constructed (i.e. extended by the 50 years of . Over the 140-year study period, a sizeable and statistically significant increase of 0.1°C per decade was found in the air temperature in Toruń. The greatest increases occurred for spring and winter, at 0.12 and 0.11°C, respectively. A lesser warming, meanwhile, was recorded for autumn (0.10°C/10 years), and particularly for summer (0.07°C/10 years). The air temperature trends are statistically significant for all seasons. Air temperature differences between the monthly averages of three analysed subperiods (1871-1900, 1901-1950 and 1951-2010) and averages for the entire period under review rarely exceeded ± 0.5°C. In all of these periods, the highest average air temperatures occurred in July and the lowest in January. The period of 1981-2010 had the highest frequency of occurrence of very and extremely warm seasons and years. Meanwhile, the highest frequency of very and extremely cool seasons and years was recorded in the 1940s and in the nineteenth century. In the period of 1871-2010, winters shortened markedly (by 7%) and summers lengthened by 3.8%. All of the presented aspects of air temperature in Toruń, which is representative of the climate of central Poland, are in close agreement with the findings of analogous studies of the same for other areas of Poland and Central Europe.

Homogenization of air temperature and its long-term trends in Poznań (Poland) for the period 1848–2016

“…The results of our analysis are in agreement with those obtained for other stations located in Central Europe. A long-term increasing trend of approximately 1°C per 100 years was also obtained by Rebetez and Reinhard (2008), Dobrovolnỳ et al (2009), Leijonhufvud et al (2010), Mikkonen et al (2015), Niedźwiedź et al (2015), Pospieszyńska and Przybylak (2018). Breaks in the longterm trend for Poznań are comparable with Warsaw (Lorenc 2000), Cracow (Trepińska and Kowanetz 1997), Wrocław Fig.…”

“…As the temperature measurement techniques changed throughout the analyzed period, the same also happened to the methodology of determining the monthly means (e.g., the number and timing of daily measurements). This issue is a typical limitation for the historical data and has been discussed in many previous studies (e.g., Trepińska 1997;Lorenc 2000;Bryś and Bryś 2010;Pospieszyńska and Przybylak 2018). Although authors are aware of this disadvantage, it is generally considered that this issue should have a minimal effect on the results.…”

“…Of the individual locations in Poland for which long-term temperature analyses in have been carried out, we may list Wrocław (period 1791-2007) presented by Bryś and Bryś (2010), Warsaw (1779-1998 by Lorenc (2000), and Cracow (1792-1995 by Trepińska (1997), Trepińska and Kowanetz (1997) and Piotrowicz (2007). Elaborations covering slightly shorter time-series concerning Gdańsk andHel (1851-1995) by Miętus (1998) and Filipiak and Miętus (2010), Bydgoszcz (1851-1990 by Vízi et al (2000), Poznań (1848Poznań ( -2009Poznań ( and 1848Poznań ( -1997 by Nyćkowiak et al (2014) and Tamulewicz (2000) respectively, Puławy (1871-1990) by Górski and Marciniak (1992), Śnieżka (1881-2010) by Migała et al (2016Migała et al ( ), Łódź (1903Migała et al ( -2000 by Wibig et al (2004), and Toruń (1871-2010) by Pospieszyńska and Przybylak (2018). The aforementioned studies and their statistical trends are compatible with those observed in neighboring countries, e.g., Potsdam in Germany (Lehmann and Kalb 1993) and Prague in Czech Republic (Brázdil et al 2012a, b).…”

“…The local aspects of changes in air temperature have often become a hot topic in discussions among local researchers who are knowledgeable of the particular location's history, changes in the station's location, measurement techniques, the exposure of instruments, and their precision (Grigull 1986;Maciążek 2005). Local researchers are also the ones best acquainted with the available data and can thus provide reliable evaluation of its quality (Pospieszyńska and Przybylak 2018). Although Poland has a long-standing research tradition into multiannual trends in temperature, it has suffered many wars and changes to its borders over the last 200 years.…”

Optical density of Scots pine wood and climatic conditions in Toruń, Poland

“…1). In terms of regional climates proposed by Okołowicz and Martyn (2004), Toruń lies in the Nadwiślański Region in a temperate warm zone of year-round precipitation. The area is subject to Atlantic, Baltic and continental influences.…”