In 2017, Hurricane Harvey’s rains flooded 204,000 homes and apartment buildings, and nearly three quarters of these lay outside the federally regulated 100-year flood plain (an area with a 1 percent probability of flooding on any given year). Hurricane Harvey delivered excessive and unusual anthropogenic climate change-related precipitation levels. But many Houstonians also believe this was not just a “natural” disaster, but a calamity whose materially and socially disruptive capacity is rooted in human development, organization, and land use practices. During the last three decades, real estate developers have skirted flood plain construction regulations, built extensive subdivisions in emergency flood sacrifice zones, and found creative ways of avoiding their responsibility to build required flood prevention infrastructure. The recovery of the city of Houston also provides a critical setting for investigating the ways disaster-affected populations wrestle with the political and epistemological dimensions of climate-change and development related disasters in the early twenty-first century.
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Disentangling the impacts of human and environmental change on catchment response during Hurricane Harvey
Flooding is a function of hydrologic, climatologic, and land use characteristics. However, the relative contribution of these factors to flood risk over the long-term is uncertain. In response to this knowledge gap, this study quantifies how urbanization and climatological trends influenced flooding in the greater Houston region during Hurricane Harvey. The region—characterized by extreme precipitation events, low topographic relief, and clay-dominated soils—is naturally flood prone, but it is also one of the fastest growing urban areas in the United States. This rapid growth has contributed to increased runoff volumes and rates in areas where anthropogenic climate changes has also been shown to be contributing to extreme precipitation. To disentangle the relative contributions of urban development and climatic changes on flooding during Hurricane Harvey, we simulate catchment response using a spatially-distributed hydrologic model under 1900 and 2017 conditions. This approach provides insight into how timing, volume, and peak discharge in response to Harvey-like events have evolved over more than a century. Results suggest that over the past century, urban development and climate change have had a large impact on peak discharge at stream gauges in the Houston region, where development alone has increased peak discharges by 54% (±28%) and climate change has increased peak discharge by about 20% (±3%). When combined, urban development and climate change nearly doubled peak discharge (84% ±35%) in the Houston area during Harvey compared to a similar event in 1900, suggesting that land use change has magnified the effects of climate change on catchment response. The findings support a precautionary approach to flood risk management that explicitly considers how current land use decisions may impact future conditions under varying climate trends, particularly in low-lying coastal cities.
more » « less- NSF-PAR ID:
- 10303250
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Environmental Research Letters
- Volume:
- 14
- Issue:
- 12
- ISSN:
- 1748-9326
- Page Range / eLocation ID:
- Article No. 124023
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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