Temporal Changes of Near‐Surface Air Temperature in Poland for 1781–2016 and in Tbilisi (Georgia) for 1881–2016

Abstract

Abstract Analyses of near‐surface air temperature T in Poland for 1781–2016 and in Tbilisi (Georgia) for 1881–2016 have been carried out. We show that the centenary warming effect in Poland and in Tbilisi has almost the same peculiarities. An average centenary warming effect ΔT = (1.08 ± 0.29)°C is observed in Poland and in Tbilisi for 1881–2016. A warming effect is larger in winter season (ΔT = ~1.15°C) than in other seasons (average warming effect for these seasons ΔT = ~0.95°C). We show that a centenary warming is mainly related to the change of solar activity (estimated by sunspot number [SSN] and total solar irradiance [TSI]), particularly, a time interval about ~70 years (1890–1960), when correlation coefficients between 11‐year smoothed SSN and T, and TSI and T are high, r = 0.66 ± 0.07 and r = 0.73 ± 0.07 for Poland and r = 0.82 ± 0.05 and r = 0.90 ± 0.05 for Tbilisi, respectively; in this period solar activity contributes decisively in the global warming. We show that a global warming effect equals zero based on the temperature T data in Poland for period 1781–1880, when human activities were relatively less than in 1881–2016. We recognize a few feeble ~20 ± 3 years of disturbances in the temperature changes for period 1885–1980, most likely related with the fluctuations of solar magnetic cycles. We distinguish the fluctuations of ~7–8 years in Poland's T data, possibly connected with local effects of the North Atlantic Oscillation.

Keywords

• near‐surface air temperature changes
• centenary changes of Earth temperatures
• global warming effect
• solar activity