Environmental Monitoring and Assessment Climate change-induced variations in future extreme precipitation intensity-durationfrequency in flood-prone city of Adama, central Ethiopia
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Date
2021-11-01
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Publisher
Springer Nature
Abstract
The influences of climate change on the features of extreme rainfall events have
become unprecedented that needs improved understanding at all levels for planning
effective management strategies of the potential risks. This study aims to assess the
potential influences of climate change on extreme rainfall characteristics in floodvulnerable
city of Adama. For this, daily precipitation records of 1967-2016 and
projection of global circulation models (GCMs): CanESM2 and HadCM3 for 2021-2070
were disaggregated into shorter time resolutions using the Hyetos model. Gumbel
Type I probability distribution and power-regression model ( [[EQUATION]] were used
for deducing intensity-duration-frequency (IDF) curves and for describing their
functions, respectively. The extreme rainfall intensity of the historical and future periods
for a range of storm durations and return periods were compared and contrasted. A
close agreement is obtained between the observed and the modeled rainfall intensity
with high values of coefficient of determination (> 0.996) and Nash-Sutcliffe efficiency
(> 0.850). Besides, statistically significant (p<0.05) direct linear relationship is found
between the return periods and the coefficient parameter of the IDF models. Moreover,
the intensity of extreme precipitation over 2021-2070 in Adama city would increase up
to 49.5%, depending on storm duration and return period considered. This could have
consequences of the way the city’s drainage infrastructures are designed, operated
and sustained. Hence, flood-prone areas should be recognized in order to formulate
effective strategies for mitigation and adaption of potential impacts. The standards for
designing future drainage infrastructures should also be updated aiming to reflect the
effects of climatic change The standards for designing future drainage infrastructures
should also be updated aiming to reflect the effects of climatic change.