Climate changes impact estimation on urban drainage system located in low latitudes districts: a study case in Fortaleza-CE

Abstract

The observed changes in extreme weather events reflect the influence of climate change caused by anthropogenic factors, in addition to natural climate variability. According to future climate projections, the increase in the average surface temperature will cause major changes in the average annual rainfall of almost the entire planet. The primary objective of this study is to evaluate the impact of possible scenarios of climate change on urban drainage system in locations situated at low latitudes. The specific location of the study was one of the Rio Cocó sub-basins in the city of Fortaleza-CE. It was used rainfall data generated by 6 (six) different global circulation models: bcc-CSM1, CanESM2, CCSM4, CESM1-CAM5, inmcm4 and MIROC5. These data were extracted and interpolated to the city of Fortaleza-CE. This information was used in order to generate new IDF equations designed for the future, by using the "Equidistance Quantile Matching Method", based on climate projections RCP 4.5 and RCP 8.5. The new values of rainfall generated by these new IDF curves were used as input data to HEC-HMS program, which is capable of calculating flow and volume disposed in a particular basin. The results showed that large increases in flow rates and volumes disposed in the analyzed drainage system will occur, and that the RCP 8.5 scenario presented even more pronounced values than the ones generated by the scenario RCP 4.5.Keywords: Climate changes; IDF curves; Global circulation models; Urban drainage. RESUMOAs alterações observadas nos eventos climáticos extremos refletem a influência das mudanças climáticas ocasionados for fatores antropogênicos, além da variabilidade natural do clima. Segundo projeções climáticas futuras, o aumento da temperatura média da superfície terrestre, ocasionará fortes mudanças nas precipitações médias anuais de quase todo o planeta. O objetivo primordial desse artigo é avaliar o impacto dos possíveis cenários de mudanças climáticas em sistemas de drenagem urbana localizados em baixas latitudes. O local específico do estudo foi uma das sub-bacias do Rio Cocó, na cidade de Fortaleza-CE. Foram utilizados dados de precipitações oriundos de 6 (seis) modelos de circulação global, são eles: bcc-csm1, CanESM2, CCSM4, CESM1-CAM5, inmcm4 e MIROC5. Esses dados foram extraídos e interpolados para a cidade de Fortaleza-CE. Essas informações foram utilizadas com o intuito de gerar novas equações IDF projetadas para o futuro, através da utilização do "Método da Correspondência de Quantis Equidistantes", baseadas nas projeções climáticas RCP 4,5 e RCP 8,5. Os novos valores de precipitação gerados por essas novas curvas IDFs foram utilizados como um dos dados de entrada do programa HEC-HMS. Os resultados mostraram que devem ocorrer grandes aumentos nas vazões e volumes escoados no sistema de drenagem analisado, sendo que o cenário RCP 8.5 apresentou valores ainda mais acentuados do que o gerado pelo cenário RCP 4,5. Climate changes impact estimation on urban drainage system located in low latitudes distric...

A coupled system based on Differential Evolution for the determination of Rainfall intensity equations

“…With respect to precipitation data, Figure 4 shows the results of the optimization process of the Gumbel model for annual maximum precipitation data observed in the region of Ribeirão Preto/SP, published and kindly provided by Penner and Lima (2016). The simulation obtained in this study ( 2 R =0.915) provides values that are similar to those obtained by Penner and Lima (2016), who used Chow's frequency factors to determine the precipitation height for each return period. Figure 5 shows a plot of the variation of the objective function along the generations for the simulation of Figure 2.…”

“…The values listed in Table 6 may be altered if the user wishes to use wider or closer bounds. Illustratively, the system described is then used to determine the IDF curves outlined by Penner and Lima (2016). Figure 6a presents IDF curves in semi-logarithmic scale for three return periods: 5, 25, and 100 years.…”

“…However, the behavior of exceptional rainfall is hard to determine, and is generally handled in a probabilistic way. These rains can be determined through rainfall intensity equations, which are broadly utilized for dimensioning drainage structures with different purposes, including agricultural (VIVEKANANDAN, 2017) and urban drainage systems (SABÓIA et al, 2017), channels (WRIGHT; SMITH; BAECK, 2014), and engineering structures in road projects (KANG et al, 2009). A precise characterization of rainfall intensity equations is therefore vital for the appropriate sizing of different drainage structures.…”

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Verification of the Stormwater Drainage System Overloads in Wrocław for an Assessment of Climate Change Effects

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