Changes in the hydrologic cycle due to increase in greenhouse gases cause variations in intensity, duration, and frequency of precipitation events. Quantifying the potential effects of climate change and adapting to them is one way to reduce urban vulnerability. Since rainfall characteristics are often used to design water structures, reviewing and updating rainfall characteristics (i.e., Intensity–Duration–Frequency (IDF) curves) for future climate scenarios is necessary.

Climate model projections suggest that future rainfall intensity could be subjected to decreases or increases depending on the different area considered, but with an increase in terms of frequency. It’s the result of a study recently published on SpringerPlus in which a team of scientists (among them, CMCC researcher Edoardo Bucchignani  from ISC Division) tried to assess how extreme rainfalls will be modified in a future climate while analyzing observed data and future simulations for three African test cities: Addis Ababa (Ethiopia), Dar Es Salaam (Tanzania) and Douala (Cameroon), characterized by different rainfall patterns.

The climate projections used, provided by CMCC, were performed following the IPCC (Intergovernmental Panel on Climate Change) 20C3M protocol for the 20th Century, and the RCP4.5 and RCP8.5 radiative forcing scenarios for the 21st century: they are characterized by horizontal resolutions of about 8 km and 1 km.

For more information, read the integral version of the paper:
De Paola F., Giugni M., Topa M. E. , Bucchignani E.
Intensity-Duration-Frequency (IDF) rainfall curves, for data series and climate projection in African cities
2014, Springerplus, Volume 3, Pages 133, DOI: 10.1186/2193-1801-3-133