A study of extreme events under climate change condition in northern part of Tehran, Iran

One of the most important consequences of climate change is the impact on extreme events regime (i.e. intensity and frequency). This study examines the impact of extreme precipitation in a changing climate on rainfall-induced runoff in West Flood-Diversion (WFD) catchment in northern part of Tehran, Iran. To do this, the output of MRICGCM3 model under RCP4.5 emission scenario was used to be able to compare annual maximum rainfall in two future time periods (2026-2042 and 2084-2100) with the baseline (1990-2006). In addition, long-term monthly average precipitation was calculated and IDF curves were extracted for the studied time periods. Afterwards, the runoff generated by extreme rainfalls was simulated using Storm Water Management Model (SWMM). The results showed that rainfall intensity and frequency increases over time and consequently, the amount and frequency of extreme discharges from the catchment increases in the future. Therefore, adapting urban infrastructures to climate change impacts seems to be necessary in WFD catchment.

کلیدواژه ها:

climate change ، extreme rainfall ، return period ، urban runoff