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 developed the climatic water balance values for all 2477 Polish municipalities (gminas) and, based on soil categories, calculated the current risk of agricultural drought.
In the first reporting period, i.e. from March 21st to May 20th, 2021 the average value of Climatic Water Balance (CWB), which is the basis for assessing the risk of agricultural drought, was negative and equalled -25 mm.
The highest water deficit was recorded in: Western and Volhynian Polesie, the Volhynian Upland, southern part of the South Podlasie Lowland, north-eastern part of the Szczecin Coastland and central part of the West Pomeranian Lake District, where it ranged from -90 to -119 mm. In the rest of the country, water deficit remained below -50 mm to -90 mm, or in places even excess of water was recorded.
Based on the humidity conditions in the current reporting period, IUNG-PIB states no agricultural drought conditions in Poland.
Values recorded in March this year remained within the multiannual norm (1990-2021). In the third decade of the month, the highest temperatures were recorded in the western part of the country, from 7 to more than 8°C. The further to the east, the colder it was. Temperatures recorded in the east ranged from 4 to only 5°C.
This year’s April was the coldest in the last 24 years. Temperatures were low across the country. In the vast area of Central Poland, the temperatures recorded were around 6°C. In the north of Poland, in the Lesser Poland Upland, Roztocze, the Sudeten and the Carpathian Foothills it was even colder, from 5 to 6°C, or in places even 4-5°C. In the Sudeten and Carpathian Mountains, temperatures were the lowest and ranged between 1-4°C. This year’s April, in relation to the multiannual norm, was colder in the south-eastern part of the country by 1°C, in the eastern part by 1-2°C, in Central Poland by 2 to 3°C, and in the western regions even by 3-4°C.
In the first decade of May, the highest temperatures were recorded in the western, south-western, southern, and south-eastern regions of Poland, ranging from 9 to 10°C, and even from 10°C to more than 11.5°C in the Sandomierz Basin. In the vast area of the country temperatures ranged from 8 to 9°C. In the north of Poland it was colder, from 7 to 8°C.
In the second decade of the month, it was significantly warmer. In the western and north-western regions of the country temperature ranged from 12 to 13°C. The further to the east, the warmer it was: from 13 to 14.5°C. Definitely the warmest region in the second decade of May was Kuyavia, with temperatures between 14.5-16°C.
In the third decade of March, very scarce precipitation was recorded throughout Poland, ranging from 5 to 10 mm or, in places, no precipitation occurred. Only in the northern and southern parts of the country precipitation was more abundant, ranging from 10 to 20 mm.
In April, in the south-eastern part of the country, high precipitation values were recorded, ranging from 60 to 120 mm (i.e. 140% of the multiannual norm). In Central Poland precipitation was also intense, although less intense than in the south-eastern part of the country, ranging from 30 to 60 mm and constituting 90-140% of the norm in this area. In the northern regions of Poland, precipitation values were the lowest, ranging from 20 to 30 mm and, in places, even below 20 mm. In these areas, precipitation constituted from 40 to more than 90% of the norm.
In May, precipitation was more diversified. The lowest precipitation values in the first decade of the month were recorded in the north-western and south-eastern regions of Poland, ranging from 10 to 30 mm. Significantly higher values, from 30 to even 80 mm, were recorded in the area extending from south-western to north-eastern parts of the country.
In the second decade of May, scarce precipitation was recorded in Western Polesie and in central part of the Greater Poland Lowland, ranging from below 5 to 10 mm. Slightly higher values, ranging from 10 to 20 mm, were recorded in the vast area of Poland. Relatively high precipitation, from 20 to more than 50 mm, occurred in central Poland, in the area extending from Gdańsk, through Łódź, Warszawa, Częstochowa, Kielce, Kraków, to Tarnów and Rzeszów. Similar precipitation values were recorded in the Sudeten Foothills, the Sudetes, Western Beskids and the Carpathians.
As stated by IUNG-PIB, water deficit in crops ranging from -50 to -119 mm, occurred in a vast area of the country. However, based on the current weather conditions, yield reduction by at least 20% at municipality (gmina) level, in relation to the yield obtained in average weather conditions, caused by water shortage, did not occur. On the contrary, in the south of the country, water resources are large and there is an excessive amount of water in agricultural fields, which may also result in a significant yield reduction in cultivated crops.
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