Climate Change Impacts in the Design of Drainage Systems: Case Study of Portugal

Abstract

This study aims to assess the necessity of updating the Intensity-Duration-Frequency (IDF) curves used in Portugal to design building storm-water drainage systems. A comparative analysis of the design was performed for the three pre-defined rainfall regions in Portugal using the IDF curves currently in use and estimated for future decades. Data for recent and future climate conditions simulated by a global/regional climate model chain (ECHAM5/MPI-OM1/COSMO-CLM) are used to estimate possible changes of rainfall extremes and its implications for the drainage systems. The methodology includes the disaggregation of precipitation up to sub-hourly scales, the robust development of IDF curves and the correction of model bias. Obtained results indicate that projected changes are largest for the plains in Southern Portugal (5 -33%) than for mountainous regions (3 -9%) and that these trends are consistent with projected changes in the long term 95 th -percentile of the daily precipitation throughout the 21 st century. We conclude for the need to review the current precipitation regime classification and change the new drainage systems towards larger dimensions to mitigate the projected changes in extreme precipitation.

A Regression Model of Stream Water Quality Based on Interactions between Landscape Composition and Riparian Buffer Width in Small Catchments

“…The thematic maps (e.g., Figures 1-3) were prepared in ArcMap software of ESRI [47], a common tool in spatial analysis of hydrologic and environmental data widely used in many studies [42,44,[48][49][50][51][52][53][54][55][56][57][58][59][60][61][62][63][64][65][66]. The base information was compiled from various spatial databases, namely the maps published by the Brazilian Institute for Geography and Statistics (https://ww2.ibge.gov.br) on the 1: 100,000 scale, and the digital terrain model obtained from the ASTER GDEN V2 satellite image with a spatial resolution of 30 m.…”

Uncertainty assessment for climate change impact on intense precipitation: how many model runs do we need?

“…Therefore, updating the existing IDF curves by taking climate change impact on the design precipitation into consideration will greatly facilitate damage limitation (Willems et al, 2012b). The expected changes in IDF statistics under climate change in different parts of the world further emphasize the urgency of this requirement (Peck et al, 2012;Willems et al, 2012b;Cheng and AghaKouchak, 2014;De Paola et al, 2014;Modesto Gonzalez Pereira et al, 2014;Latifa et al, 2015;Tabari et al, 2016b).…”

Controls and forecasts of nitrate yields in forested watersheds: A view over mainland Portugal

“…Although yields keep the North-south gradient, average S 4 yields in 2025 or 2045 will no longer exceed 80 kg·ha − 1 ·yr − 1 (i.e., the highest class will disappear) while most yields in the south will drop to values below 2 kg·ha − 1 ·yr −1 , representing a new class. It is worth noting that climate related parameters such as R may have a contrasting effect (increase) on the yields because extreme precipitation events are expected to become more frequent in the near future (Pereira et al, 2013(Pereira et al, , 2014b. However, the design of a climate change scenario is beyond the scope of this paper.…”