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 (gminas) and, based on soil categories, assessed the current risk of agricultural drought.

In the fourteenth reporting period, i.e. from August 1st t° September 30th, 2022, the average value of Climatic Water Balance (CWB), which is the basis for assessing the risk of agricultural drought, was negative and equalled -16 mm. In the current sixty-day reporting period, the average CWB value has decreased in relation to the previous reporting period (July 21st to September 20th) by 20 mm.

The highest water deficit, ranging from -120 to -139 mm, occurred in the eastern part of the Masurian Lake District, and on the Slovincian Coast, however, it did not exceed the critical value (of 20% yield loss) in the monitored crops. In the vast area of the country, water deficit ranged from 0 to -119 mm, and in some places even positives values of CWB were recorded.

Based on the humidity conditions in the fourteenth reporting period, IUNG-PIB states no agricultural drought occurrence in the area of Poland.

In July, the lowest temperatures occurred in the north of Poland, ranging from 16 to 18°C. The further to the south, the higher was the temperature, ranging from 18 to 20°C. The highest temperature in July was recorded in the Silesian Lowland, exceeding 20°C.

In August, the highest temperatures were recorded in the Greater Poland Lake District and the Greater Poland Lowland, in the southwestern part of the Masurian Lake District and in the northern part of the Masovian Lowland, ranging from 21 to 22.5°C. In these areas, temperatures exceeded the multiannual norm of 1991-2020 by 2.5 to 3.5°C. In the rest of the country, temperatures ranged from 19 to 21°C and exceeded the multiannual norm by 1 to 2.5°C.

In the first decade of September, it was still warm in the southwestern part of the country, with temperatures ranging from 14.5 to 17.5°C. The further to the northeast, the lower temperatures were recorded. In the Podlasie Lowland and in the eastern regions of the Masurian Lake District, temperature reached only 9.5°C. In the second decade of the month it was colder, with temperatures ranging from 12 to 13°C in the western regions of Poland. In central and southeastern Poland, temperatures ranged from 11 to 12°C, and in the northeastern regions from 10 to 11°C. The lowest temperatures were recorded in the Sudetes and the Western Beskids, from 5 to 10°C. In the third decade, in the vast majority of the country temperatures ranged from 9 to 10°C, only on the Slovincian Coast it was warmer, with temperatures ranging from 10 to 12°C, whilst in the south of Poland temperatures were lower, from 4 to 8°C.

In July, the lowest insolation was recorded in the northeastern part of the country, from 200 to 240 hours. The further to the south and southwest especially, the higher was that number, reaching from 240 to 260 hours.

In August, the highest insolation was recorded in the northern and eastern Poland, ranging from 260 to 290 hours, and exceeding the norm by 10-50 hours. Especially high insolation was recorded in the Podlasie Lowland, in the northern part of Lublin Polesie, and in the western part of the Slovincian Coast, from 280 to 290 hours.

In the first decade of September, the highest insolation was recorded in the southern part of the Masovian Lowland, in the eastern part of the Greater Poland Lake District and the Greater Poland Lowland, in the Szczecin Lowland and in Lublin Polesie, where it ranged from 85 to 95 hours. In the rest of the country, sunshine duration ranged from 60 to 85. In the second decade of the month, the highest insolation was recorded in the Vistula Fens, Kuyavia and the Slovincian Coast, from 45 to 60 hours. In the northeastern part of the country, sunshine duration ranged from 30 to 45 hours and in the rest of the country only from 15 to 30 hours. In the third decade of the month, in the majority of the country, sunshine duration ranged from 35 to 45 hours, with higher values on the Slovincian Coast (45-65 hours) and lower in the south of Poland (20-35 hours).

In July, low precipitation was recorded in the west of Poland, ranging from 30 to 70 mm and constituting 30-90% of the multiannual norm. In the rest of the country, precipitation was more intense and ranged from 70 to 110 mm (80-110% of the norm), and in the eastern and southern parts of the country, it reached even 130 mm (110-150% of the norm).

In August, in the northern, northeastern and eastern parts of Poland, precipitation ranged from 30 to 60 mm (20-100% of the multiannual norm). Whilst in the southwestern regions of the country, precipitation was considerably higher, ranging from 60 to even 210 mm (in the Sudeten Foothills) and constituted 100-200% of the norm.

In the first decade of September, precipitation was also intense, ranging from 35 to 75 mm in the area of the Silesian and the Kraków-Częstochowa Uplands. Only slightly lower values, from 35 to 70 mm, were recorded in the Silesian, Greater Poland and Podlasie Lowlands and in the eastern part of the Lublin Upland. In the rest of the country, precipitation was lower and ranged from 5 to 35 mm. In the second decade of the month, the highest precipitation was recorded in the Carpathian Foothills and in the Western Beskids, from 75 to even 160 mm. Intense rainfall was also recorded in the Slovincian Coast, from 40 to 135 mm. In central Poland, precipitation ranged from 5 to 10 mm, and in the rest of the country from 10 to 40 mm. In the third decade of the month, precipitation was relatively low in the western regions, ranging from 10 to 30 mm. It was higher in the eastern part of the country, ranging from 40 to 70 mm, whilst in the Carpathian Foothills and the Western Beskids precipitation was very intense and ranged from 70 to 130 mm.

Both in the first and in the second agricultural drought reporting period, relatively low evapotranspiration values were recorded, namely, 2.5 mm/day. Due to higher precipitation values recorded in the second and third decade of May, water deficit decreased in relation to the first reporting period. In the third report, however, evapotranspiration increased to the value of 2.9 mm/day, in the fourth report to 3.3 mm/day, in the fifth to 3.8 mm/day, in both the sixth and seventh report it reached the value of 3.9 mm/day, in the eighth and tenth equalled 4.1 mm/day, whilst in the ninth 4.2 mm/day. In the eleventh reporting period, on the other hand, evapotranspiration has decreased to the value of 3.6 mm/day, in the twelfth to 3.5 mm, in the thirteenth to 3.0 mm, and in the fourteenth to 2.4 mm, which was the lowest value in this year’s growing season.

This year’s weather conditions, considering:

• high insolation (3rd decade of March, 1st and 2nd decade of May, and 3rd decade of June),
• low insolation (2nd and 3rd decade of September),
• high wind speed (1st decade of April, 3rd decade of May),
• low air humidity (3rd decade of March, 1st and 2nd decade of May, and 3rd decade of June),
• high air humidity (3rd decade of September),
• high air temperature (June, August),
• low air temperature (3rd decade of September),
• low precipitation (2nd decade of March, 3rd decade of April, 1st and 2nd decade of May, 3rd decade of June, 2nd decade of July, and 1st decade of August),
• high precipitation in July, 2nd and 3rd decade of August, and 1st and 2nd decade of September,
• high potential evapotranspiration (3rd decade of July, and 1st and 2nd decade of August),
• low evapotranspiration in the 2nd and 3rd decade of September,

have led to a high water deficit for all the monitored crops across the country, resulting in yield losses due to water shortage in all the monitored crops in Poland in the summer. Whilst lower water deficit recorded in September did not result in agricultural drought occurrence causing a 20% yield reduction.

We would like to inform that in accordance with the definition included in the Act of 7 July 2005 on insurance of agricultural crops and livestock (Journal of Laws No. 150, item 1249, as amended): “drought” means damage caused by the occurrence, in any sixty-day period from March 21st to September 30th, of a decline in the climatic water balance below the value specified for each crop species and soil type”. Thus, occurrence of drought in whichever sixty-day reporting period causes yield reduction by at least 20% at municipality level in relation to the yield obtained in the multiannual average weather conditions.

In this year's growing season, from March 21st t° September 30th, fourteen agricultural drought monitoring reports have been prepared. During this reporting period, water shortages reducing yield by at least 20% compared to the yield obtained in average weather conditions were recorded for the following crops:

• Spring cereals,
• Winter cereals,
• Fruit shrubs,
• Rapeseed and turnip rape (spring),
• Strawberries,
• Maize for silage,
• Maize for grain,
• Legumes,
• Ground vegetables,
• Tobacco,
• Potatoes,
• Fruit trees,
• Hops,
• Sugar beet,
• Rapeseed and turnip rape (autumn).

The occurrence of such yield losses in the country in the period of March 21st – September 30th, 2022, is presented in table 1.

Table 1. Agricultural drought in Poland in the period of March 21st - September 30th, 2022.

Below are presented the final results on agricultural drought in the 2022 growing season on the country and voivodeship scale, for all the monitored crops (tab. 6-16).

Table 2. Agricultural drought in spring cereals in Poland, 2022, at voivodeship and country scale.

Table 3. Agricultural drought in winter cereals in Poland, 2022, at voivodeship and country scale.

Table 4. Agricultural drought in fruit shrubs in Poland, 2022, at voivodeship and country scale.

Table 5. Agricultural drought in rapeseed and turnip rape (spring/summer) in Poland, 2022, at voivodeship and country scale.

Table 6. Agricultural drought in strawberries in Poland, 2022, at voivodeship and country scale.

Table 7. Agricultural drought in maize for silage in Poland, 2022, at voivodeship and country scale.

Table 8. Agricultural drought in maize for grain in Poland, 2022, at voivodeship and country scale.

Table 9. Agricultural drought in legumes in Poland, 2022, at voivodeship and country scale.

Table 10. Agricultural drought in ground vegetables in Poland, 2022, at voivodeship and country scale.

Table 11. Agricultural drought in tobacco in Poland, 2022, at voivodeship and country scale.

Table 12. Agricultural drought in potatoes in Poland, 2022, at voivodeship and country scale.

Table 13. Agricultural drought in fruit trees in Poland, 2022, at voivodeship and country scale.

Table 14. Agricultural drought in hops in Poland, 2022, at voivodeship and country scale.

Table 15. Agricultural drought in sugar beets in Poland, 2022, at voivodeship and country scale.

Table 16. Agricultural drought in rapeseed and turnip rape (autumn) in Poland, 2022, at voivodeship and country scale.

Detailed data on yield losses incurred in particular voivodeships presented using maps and tables are available on the website of the Agricultural Drought Monitoring System at: www.susza.iung.pulawy.pl.

It is worth noting that only the maximum range is the most reliable for indication of drought occurrence at the level of the country, voivodeship, municipality and cadastral parcels.

Executive Director

Prof. dr hab. Wiesław Oleszek

Report prepared by: 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, Adrian Matczuk, Mgr Beata Murat, Mgr Agata Ścibior