Precipitation forecast model up to year 2050 – Bydgoszcz

Precipitation forecast model (design rainfall) up to year 2050 based on the climate change scenario used for urban hydrology of the city of Bydgoszcz.


Project aim

The aim of the study was to prepare a precipitation forecast model (design rainfall) up to 2050 for the city of Bydgoszcz considering at least one climate change scenario assuming the average climate change e.g. A1B following 4 Report of the IPCC or RCP4.5 following 5 Report of the IPCC.


Project description

The detailed study included:

  • Reading changes in annual maximum precipitation intensity in Bydgoszcz for a given scenario (in accordance with A1B or RCP4.5 scenarios);
  • Rescalling of annual maximum precipitation intensity, with respect to a selected scenario of climate change, to maximum rainfall intensity for short-term precipitation amounting to 5,10,15,  30, 45,   60,   90,   120,   180,   360,   720,   1080   respectively, meeting the requirements of European standard PN-EN-752 of precipitation probability where p equals  10%, 20%, 50% and 100%;
  • Summary of precipitation height and intensity as for the prepared precipitation time models of 5, 10 ,15, 30, 45, 60, 90, 120, 180, 360, 720, 1080 and 1440 min. and probability of p=10%, 20%, 50% and 100% for up to year 2050;
  • Preparing precipitation model up to year 2050 in the form of a set of calculation formulas that allow to calculate the amount of design rainfall on the basis of its time and probability;


  • Comparing precipitation intensity using the model up to year 2050 with the amount of design rainfall according to the current design rainfall intensity model;
  • Presenting the preparation of an example model precipitation of Euler’s type II prepared using design rainfall intensity forecast up to year 2050.



Solutions adopted

The analytical data used to prepare this study was among others the reading of annual change in day precipitation extremes in Bydgoszcz with respect to climate changes of medium level changes RCP 4.5, following 5 Report of the IPCC.