Increasing storm vulnerability of coastal cities fueled by climate change and growth

Warm water in the Atlantic Ocean and Gulf of Mexico can fuel powerful hurricanes, but how destructive a storm becomes depends not only on climate and weather, but also on the people and property affected.

In many coastal cities, rapid population growth has left more people living in areas at high risk of flooding.

I am a geographer studying the human dimensions of climate change and natural disasters. My research and mapping with colleagues shows that socially vulnerable communities—those least able to prepare for or recover from disasters—tend to be concentrated in areas that are more susceptible to flooding, especially along the Gulf Coast.

Larger, vulnerable populations

Almost 40% of the US population today lives in a coastal county. Many of these areas are increasingly vulnerable to disasters, including hurricanes and high-tide flooding, which have been exacerbated by rising sea levels.

The Gulf of Mexico region, in particular, is prone to concurrent climate change-induced disasters—when multiple disasters strike simultaneously. For example, when Hurricane Beryl hit Texas in July 2024, 3 million homes and businesses lost power for several days in the sweltering summer heat—in addition to dealing with heavy rain and flooding.

To further complicate matters, more than a fifth of the population of Harris County, where Houston is located, is considered socially vulnerable, meaning people who are likely to be more susceptible to injury from extreme weather.

Socially vulnerable populations in the US include many older adults, people with disabilities, people living in poverty, mobile home residents, and other marginalized groups. They often don’t have the resources or physical capacity to prepare for a storm or the means to rebuild afterward.

Several cities along the Gulf Coast – including Houston; New Orleans; Mobile, Alabama; and Tampa, Florida—have large socially vulnerable populations that are at high risk of hurricane damage. In many of these cities, land development patterns and political decisions have increased the potential for harm.

Unbridled urban sprawl

Houston provides a case study in the challenges created by rampant urban sprawl in coastal cities.

Harris County grew by a third from 2000 to 2023, adding 1.3 million residents to become the third most populous county in the US. The economic boom that accompanied this population growth brought jobs to the county, but not all of those jobs are well-paying. Harris County’s poverty rate is 16.5 percent, well above the national average of 11.5 percent.

Following the widespread damage caused by Hurricane Harvey in 2017, a heated debate ensued. Many observers pointed out a thorny reality: Houston was built on a swamp. The laissez-faire mentality typical of Texas politics, which prioritizes non-intervention in growth, has further contributed to rampant urban sprawl, turning wetlands into concrete terrain. With the wetlands simply paved over, heavy rains could not be easily absorbed, making the new neighborhoods extremely vulnerable to flooding.

My research group’s preliminary research, which focuses on risk decision making, finds that of all land use and land cover types in Harris County, developed land has grown the fastest, increasing from 35 percent of county land in 2000 to 50% in 2020.

Harvey was a living example of the importance of stormwater planning in urban development. However, as the storm’s devastation fades into collective memory, more people are moving to Houston.

With such a high concentration of people and infrastructure in the coastal region, more people are at risk. More people means that when disaster strikes, the impact can be much greater than it was a few decades ago.

Preparing for future disasters

Coastal communities cannot afford to wait for the wake-up call of a disaster to invest in protecting them. To prepare for future disasters, I think they need to rethink urban development with climate change in mind.

Increasing resilience includes improving flood control infrastructure and improving emergency response capabilities as storms worsen. It also involves adopting zoning rules that limit building in flood-prone areas. And it may even involve a managed withdrawal – using acquisitions to move some communities to safer ground.

Public education campaigns are also important to raise awareness of disaster risks. Accurate flood risk maps, for example, can motivate people to buy insurance, choose their locations more carefully and prepare their homes for local risks. Successful awareness campaigns often partner with grassroots organizations to expand community networks and reach out to their vulnerable populations to help them prepare.

This article is republished from The Conversation under a Creative Commons license. Read the original article here: https://theconversation.com/coastal-cities-growing-hurricane-vulnerability-is-fed-by-both-climate-change-and-unbridled-population-growth-234547.

Copyright 2024 Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

TOPICS
Storm Climate Change