Researches trace four decades of climate change in the South-Eastern Baltic region: more hot days, fewer frost days
Researcher from the Laboratory of Dara Gaeva, together with colleagues from Immanuel Kant Baltic Federal University, have analyzed changes in extreme climate events in the south‑eastern Baltic region over the past 40 years (1981 – 2020). The results, published in Theoretical and Applied Climatology in the article “Four decades of climate change (1981–2020) in the South-Eastern Baltic region: trends and spatial patterns of air temperature and precipitation extremes”, show that the region is becoming significantly warmer, with heatwaves occurring more often and lasting longer
The team used long-term climate records from nine coastal and inland meteorological stations in Russia and Poland. To characterize extreme events, they applied ETCCDI (Expert Team on Climate Change Detection and Indices) indicators and statistical methods for trend analysis. The study revealed a robust, statistically significant increase in the number of hot days and heatwaves at most stations. Particularly strong growth was found in the number of summer days with maximum air temperature above +25 °C, anomalously warm days, and in the frequency and duration of heatwaves, while the number of frost days decreased, indicating a pronounced regional warming. The most intensive changes were observed in inland areas away from the Baltic Sea coast.
Trends in precipitation-related indices turned out to be more complex. In some parts of the region, the number of days with extreme rainfall increased, whereas at several coastal stations the total amount of precipitation declined. The analysis showed that rising sea surface temperature in the Baltic and the behaviour of large-scale atmospheric circulation patterns – the Arctic Oscillation (AO), the North Atlantic Oscillation (NAO) and the Scandinavian pattern (SCAND) – are closely linked to year-to-year variability of temperature extremes. Statistically significant relationships were found between the number of anomalously warm and frost days and the AO index, between the number of days with intense precipitation and the AO and NAO indices, as well as between annual precipitation totals and the NAO and SCAND indices. Among temperature indices, the strongest links with sea surface temperature were identified for the number of summer days, anomalously warm days, the frequency of heatwaves and the number of frost days.
According to the authors, these findings are crucial for assessing climate risks in the region, including impacts on public health, urban infrastructure, tourism and natural ecosystems of the Baltic. A longer warm season may increase the region’s attractiveness for tourism, but at the same time it can intensify pressure on protected natural areas and raise the risks associated with heatwaves and heavy rainfall events.
Gaeva, D.V., Barinova, G.M. & Yu, R.A. Four decades of climate change (1981–2020) in the South-Eastern Baltic Region: trends and spatial patterns of air temperature and precipitation extremes // Theor. Appl. Climatol. 157, 302 (2026). https://doi.org/10.1007/s00704-026-06207-w
