The aim of the study was to attempt to estimate the demand for water for upward irrigation of urban green areas in parks of four selected cities in the Kuyavian-Pomeranian Voivodeship (Bydgoszcz, Grudziądz, Toruń, Włocławek) depending on expected climate changes. The study takes into account two scenarios: the RCP 4.5 scenario assuming an increase in CO2 concentration to the level of 540 ppm in 2100 and achieving radiative forcing of 4.5 W/m2, and the RCP 8.5 scenario assuming an increase in CO2 concentration to 940 ppm in 2100 and achieving radiative forcing of level 8.5 W/m2. Three selected decades (decades) of the 21st century are included: 2021-2030, 2051-2060 and 2091-2100. Based on the adopted assumptions and calculations, it was found that the largest amounts of water for irrigation will be needed in the last decade of the 21st century. The greatest demand for water will occur in July, and then in August. Higher water needs of urban green areas - compared to the RCP 4.5 scenario - (except for Grudziądz) were found in the RCP 8.5 scenario. Among the four examined cities in the Kuyavian-Pomeranian Voivodeship, the lowest demand for water occurred in Grudziądz, higher in Bydgoszcz, even higher in ...
The study aimed to determine the differences in lawn irriga-tion needs resulting from the topographical heterogeneity of the city of Bydgoszcz and surrounding areas. To gather the data, me-teorological measurements were carried out in the period from May to September 2012-2014, in areas diversified in terms of the degree of urbanization and land cover: the center of a large city, urban peripheries and rural area. Based on the calculated water needs of the lawn, the range of rainfall deficits during the lawn growing period was determined. It was found that seasonal rain-fall totals in the compared locations were at a similar level, but a large temporal variability of this indicator was observed in indi-vidual seasons. In terms of evapotranspiration, clear differences were noted between the analysed locations. On average, the high-est amounts of potential evapotranspiration were found in the city center, which may be the result of the urban heat island phenome-non forming over this area. However, the lowest water loss due to evapotranspiration took place in the rural area. As a result of these, the analysis showed that the lawn's irrigation needs were characterized by both temporal and spatial variability. By far the greatest irrigation needs occurred in urban ...
