Early Instrumental Weather Observations From Ukraine: The ClimUAsd‐Stn.v2 Dataset, 1808–1880

ABSTRACT In this study, we present ClimUAsd‐stn.v2, an updated publicly open version of the digital dataset of the earliest instrumental weather observation conducted in Ukraine. Compared to the first version, ClimUAsd‐stn.v2 extends the temporal coverage of the rescued meteorological records from 1808–1850 to 1808–1880 and incorporates data from four additional stations. The dataset primarily consists of rescued sub‐daily measurements of air temperature (ta) and atmospheric pressure (p). In its updated version, ClimUAsd‐stn.v2 includes an additional 180,101 temperature and 167,274 pressure records, bringing the total to 334,963 and 290,608 values, respectively. These measurements were collected at 12 stations during the 19th century. The rescued time series were quality controlled using the dataresqc software. Its iterative use revealed 1714 (~0.5%) erroneous and 6865 (~1.1%) suspicious values. In addition, the rescued meteorological data were compared with corresponding reference time series derived from the independent 20CRv3 historical reanalysis. The qualitative comparison (through visual inspection of time series plots) helped to identify 6624 (~1.1%) errors that remained in ClimUAsd‐stn.v2 after the dataresqc application. The quantitative statistical comparison (performed after the correction of all detected errors) demonstrated generally good agreement between the rescued records and the reanalysis data. The ClimUAsd‐stn.v2 dataset contributes to the update of the already existing digitised Ukrainian archives of original meteorological measurements in the 19th century. The rescued data have great potential to be used in regional climate analysis and improve historical reanalysis. In addition, they can be used to enhance regional and global historical reanalyses, refine understanding of climate variability and compound extremes, and support interdisciplinary studies linking past weather, societal impacts and environmental crises.