Uncertainties as to how the climate will change and how it will influence the necessities and trends of irrigation development are the serious questions to be answered in the near future. How irrigation and water systems will have to adapt to climate changes is the challenge that planners, designers and O&M ser-vices will have to cope with. It is widely accepted that air temperature will increase of 2–4°C in Po-land. Changes in total seasonal precipitation or its pattern of variability are both important. There is rather an agreement that total yearly precipitation will not be changed but its pattern in the year will change towards greater amount in winter and less in summer. Moreover, evapotraspiration and crop water demands can increase due to increased temperatures and the extent of the length of growing season. Thus soil moisture can be depleted more quickly during the growing sea-son, while surface runoff and groundwater recharge decreased. Due to climate change and related extreme meteorological and hydrologi-cal events (droughts), it is indispensable to review planning principles, design criteria, operating rules, contingency plans and management policies for water infrastructures and to stress the role of irrigation and agricultural water man-agement to control extreme meteorological ...
Meteorological conditions have a considerable impact on water relations and the state of forest hydrogenic habitats. Variation in atmospheric precipita-tion and air temperatures are of particular relevance. The presented meteoro-logical parameters obtained between 1986 and 2008 from the meteorological station in Zielonka included: annual and halfyear precipitation sums; drought frequencies; number of days by quantity; mean annual and half-year air tempera-tures; number of days of different temperature categories; duration of the mete-orological growing season; beginning and completion of the meteorological growing season. The study results indicated the occurrence of changes in the values of the above-specified parameters. From 1987 to 2007 the mean precipitation value was 541 mm. In Zielonka nearly 5 droughts in a year and 2–3 during the summer half-years were noted. In recent years, a decrease in days with precipitation below 1 mm and above 20 mm was recorded. The mean annual air temperatures and mean temperatures of the winter and summer halfyears show a rising tendency. This is the result of changes in the number of days with extreme temperatures. In recent years, the number of days with the average temperature between -5.0 and 15.0°C has decreased while the number of days with temperature above ...
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 ...
