Communication report regarding the incidences of drought conditions in Poland

The Institute of Soil Science and Plant Cultivation – State Research Institute, in accordance with the Act of the Minister of Agriculture and Rural Development, has calculated the climatic water balance values for all 2477 Polish municipalities and, based on soil categories, assessed the current risk of agricultural drought.

In the second reporting period, i.e. from April 1st to May 31st, 2023, the average value of Climatic Water Balance (CWB), which is the basis for assessing the risk of agricultural drought, was negative and equalled -70 mm. In relation to the previous sixty-day reporting period (March 21st – May 20th) is has decreased by 41 mm.

The highest water deficit, ranging from -150 to -169 mm, occurred in the area of the Southern Baltic Coast, the Vistula Fens, in the northern part of the Masurian Lake District and the western part of Kujavia. Significant water deficit was also recorded in the Pomeranian Lake District, the Greater Poland Lake District (in the southern part), and also in the remaining part of the Masurian Lake District and the southern Greater Poland Lowland, ranging from -120 to -149 mm. Slightly less severe water shortages, from -90 to -119 mm occurred to the south of the abovementioned regions, whilst in the south water deficit remained in the range of 0 do -89 mm.

Based on the humidity conditions in the first reporting period, IUNG-PIB states agricultural drought occurrence in the area of Poland.

Agricultural drought occurred in the following voivodeships:

• Pomorskiego,
• Zachodniopomorskiego,
• Kujawsko-pomorskiego,
• Warmińsko-mazurskiego,
• Wielkopolskiego,
• Łódzkiego,
• Mazowieckiego,
• Podlaskiego,
• Dolnośląskiego.

Agricultural drought occurred in four crops:

• Spring cereals,
• Winter cereals,
• Strawberries,
• Fruit shrubs.

In the second reporting period, from April 1st to May 31st, 2022, agricultural drought affected spring cereals the most. Drought was recorded in 676 municipalities (27.29% of all municipalities in Poland), in the area of 8.21% of arable land. Detailed data on drought occurrence in spring cereals in particular voivodeships are presented in table 1.

Table 1. Agricultural drought in spring cereals

Agricultural drought also occurred in winter cereals. It was recorded in 538 municipalities (21.72% of all municipalities in Poland), in the area of 4.40% of arable land. Detailed data on drought occurrence in winter cereals in particular voivodeships are presented in table 2.

Table 2. Agricultural drought in winter cereals

In this sixty-day reporting period, agricultural drought was also recorded in strawberries. It occurred in 414 municipalities (16.71% of all municipalities in Poland), in the area of 3.25% of arable land. Detailed data on drought occurrence in strawberries in particular voivodeships are presented in table 3.

Table 3. Agricultural drought in strawberries

Agricultural drought affected fruit shrubs as well. It was recorded in 196 municipalities (7.91% of all municipalities in Poland), in the area of 0.83% of arable land. Detailed data on drought occurrence in fruit shrubs in particular voivodeships are presented in table 4.

Table 4. Agricultural drought in fruit shrubs

The air temperatures recorded in this year’s April were average. The lowest mean temperature in the area of Poland was in the range from 6 to 7°C and was recorded in the northern part of the Pomeranian Lake District. However, in the southern part of the Pomeranian Lake District, in the Masurian Lake District, the Silesian and Greater Poland Lowlands, Roztocze, the Subcarpathians and the Sudeten Foothills temperature was higher and ranged from 7 to 8°C. In the rest of the Polish territory, temperatures ranged from 8 to 10°C.

In May, the air temperature was relatively low. In the first decade, temperature ranges from 8 to 10° in the east and from 10 to 12° in the west of Poland. The second decade was warmer, with temperatures ranging from 10 to 12° in the south and from 12 to 14° in the rest of the country. The third decade was the warmest, with temperatures from 15 to 17°C in Kujavia, the eastern part of the Greater Poland Lake District, the northern part of Masovia, in the Lublin region and the Sandomierz Basin.In the rest of the country temperatures ranged from 12 to 15°C.

The third decade of May was characterized by very high insolation. Over 100 hours of sunshine were recorded throughout Poland, while in the eastern part of The Slovincian Coast and Lublin Polesie there were even 150 hours of sunshine.

April in terms of precipitation was very diverse. In the north of Poland, precipitation values ranged from below 10 to 20 mm, and constituted less than 70 to 80% of the multiannual norm (1991-2020). In the south of the country precipitation ranged from 30 to 50 mm, and even from 60 to 80 mm by the border, which constituted from 100 to 170% of the norm. In the rest of the country precipitation ranged from 20 to 30 mm (ca. 100% of the norm).

In the first decade of May, precipitation throughout the country was scarce, in the north of Poland even less than 5 mm. However, in Lesser Poland and in the northern part of the Lublin region, precipitation was more intense, ranging from 20 to 40 mm. In the rest of the country, precipitation from 5 to 20 mm was recorded. In the second decade of the month, precipitation was higher, ranging from 25 to 85 mm in the south-eastern part of Poland, and from 10 to 25 mm in the rest of the country. Particularly scarce precipitation was recorded in the third decade of the month: in the vast majority of Poland either no rainfall occurred or it did not exceed 5 mm, only locally in the western regions precipitation ranging from 5 to 10 mm was recorded.

In the first agricultural drought reporting period, relatively low evapotranspiration values were recorded, namely, 2.0 mm/day, whilst in the second reporting period they increased to 2.5 mm/day.

Lack of rainfall, especially in the third decade of May, resulted in a higher water deficit compared to the first reporting period. Crop water shortages are increasing. Considerable water shortages were recorded in particular in the north-western regions of the country, ranging from -160 to -169 mm.

In this sixty-day reporting period, the greatest crop water shortages were recorded in the north of Poland and ranged from -120 to -169 mm. According to the current weather conditions, crop losses due to water deficit, resulting in yield reduction by at least 20% at the scale of municipality, in relation to yield obtained in multiannual average weather conditions, occurred in spring and winter cereals, strawberries and fruit shrubs. On the other hand, in the south of the country, water resources are large, and there is an excess of water in agricultural fields, which may also result in a significant reduction in crop yields.

The prevailing weather conditions this spring, due to high insolation and very scarce precipitation, resulted in crop losses due to water deficit in nine voivodeships. No such losses were recorded in the following voivodships: Lubelskie, Lubuskie, Małopolskie, Opolskie, Śląskie, Świętokrzyskie and Podkarpackie.

Executive Director

Prof. dr hab. Wiesław Oleszek

Dr hab. Andrzej Doroszewski, prof. IUNG-PIB, Dr hab. Rafał Pudełko, Dr Katarzyna Żyłowska, Dr Jan Jadczyszyn, Mgr Piotr Koza, Mgr Anna Jędrejek, Mgr Małgorzata Kozak, Mgr Tomasz Jóźwicki, Mgr Beata Murat, Adrian Matczuk