Urbanization exacerbated the rainfall and flooding caused by hurricane Harvey in Houston

• Published in: Nature (London) Vol. 563; no. 7731; pp. 384 - 388
• Main Authors: Zhang, Wei, Villarini, Gabriele, Vecchi, Gabriel A., Smith, James A.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.11.2018; Nature Publishing Group
• Subjects: 704/106/35; 704/242; Anthropogenic climate changes; Anthropogenic factors; Basins; Climate change; Climate Change - statistics & numerical data; Climate models; Coastal zone; Computer simulation; Cyclones; Cyclonic Storms - statistics & numerical data; Disasters - statistics & numerical data; Environmental aspects; Experiments; Extreme weather; Flood damage; Flooding; Floods; Floods - statistics & numerical data; Forecasting; Global climate; Global climate models; Global temperature changes; Human Activities; Humanities and Social Sciences; Hurricanes; Hydrology; Hydrometeorology; Letter; Mathematical models; Meteorological research; Meteorology; Models, Theoretical; multidisciplinary; Numerical forecasting models; Numerical models; Precipitation; Precipitation (Meteorology); Probability; Rain; Rainfall; Rainfall-climatic change relationships; Runoff; Science; Science (multidisciplinary); Statistical analysis; Statistical models; Storm damage; Storms; Stream flow; Texas; United States; Urbanization; Weather; Weather forecasting; Texas; United States; United States > US; Flood Response; Urban NO; Total Storm Rainfall; Unprecedented Flood; Houston Area
• ISSN: 0028-0836; 1476-4687
• DOI: 10.1038/s41586-018-0676-z

Category 4 landfalling hurricane Harvey poured more than a metre of rainfall across the heavily populated Houston area, leading to unprecedented flooding and damage. Although studies have focused on the contribution of anthropogenic climate change to this extreme rainfall event 1 – 3 , limited attention has been paid to the potential effects of urbanization on the hydrometeorology associated with hurricane Harvey. Here we find that urbanization exacerbated not only the flood response but also the storm total rainfall. Using the Weather Research and Forecast model—a numerical model for simulating weather and climate at regional scales—and statistical models, we quantify the contribution of urbanization to rainfall and flooding. Overall, we find that the probability of such extreme flood events across the studied basins increased on average by about 21 times in the period 25–30 August 2017 because of urbanization. The effect of urbanization on storm-induced extreme precipitation and flooding should be more explicitly included in global climate models, and this study highlights its importance when assessing the future risk of such extreme events in highly urbanized coastal areas. Modelling the contribution of urbanization to the impacts associated with hurricane Harvey in August 2017 shows that urbanization worsens rainfall and flooding.