Climate changes in the Central and North-Eastern parts of the Polish-Lithuanian commonwealth from 1656 to 1685

Abstract

The aim of this article is to examine variability of climatic conditions between the years 1656 and 1685, a period chronicled in a diary kept by Jan Antoni Chrapowicki. Scholars who have been involved in the reconstruction of climatic conditions on the basis of this diary have been hindered in their work by the fact that not all of the Polish voivode's original diary entries for the period in question are extant, with only the first 9 years of the study period as a whole (1656-1664) being covered comprehensively. Luckily, there exist two transcripts of the diary from the eighteenth and nineteenth centuries, though their fidelity to the original is doubtful as they contain numerous abbreviations and simplifications. The eighteenth-century copy, which covers all the years of the original diary, is particularly dubious with regard to entries concerning weather conditions. The nineteenth-century transcription is considerably more accurate, but only covers the years 1663 to 1667. As such, so far the only climatic analysis which has been carried out on the basis of Chrapowicki's data has been for the years from 1656 to 1667. The present article derives information on the climatic conditions for the period 1668 to 1685 from the eighteenth-century copy. These data are statistically adjusted on the assumption that the climate remained stationary throughout the study period (1656-1685). Methodological details of the climatic reconstruction have been provided. Analysis of annual temperature conditions during the period 1656-1685 demonstrates that it was cooler, not only in comparison with contemporary conditions, but also in comparison with the conditions prevailing during Chrapowicki's lifetime. The greatest negative anomalies during this period may be noted in spring and (to a lesser extent) in autumn. On the other hand, summer and winter are closest to the climatic norms of the period, according to our calculations, though on average they were also slightly cooler. However, in comparison to contemporary climatic conditions, summer was somewhat warmer while the remaining seasons were far cooler. Atmospheric precipitation calculated according to frequency of occurrence did not differ significantly from present-day conditions. © Springer Science + Business Media B.V. 2010.