If you want to escape the inevitability of a changing climate, head for Syracuse, New York. The fifth-most populous city in New York ranks first on a recent list of safest places to move to avoid the climate emergency. Cooler temperatures, the stability of proximity to fresh water, and relative protection from the increasing severity of hurricanes, wildfires, and drought make central and western New York a so-called “climate haven.”

The population of Syracuse has been dwindling for decades. In the postwar boom between 1940 and 1950, the city gained 15,000 residents, spurring economic growth and an influx of employment. But every U.S. census since 1950 has signaled a net-outward migration from the stagnant region into more economically dynamic zones. 

“Economically dynamic” might as well be synonymous with urban sprawl. The outer limits of American cities are expanding, and this sprawl is at the forefront of the climate catastrophe. According to data from the 2020 census, already low-density cities like Houston and Miami are becoming even larger and spread-out.

These are also the cities most vulnerable to climate change. Although sea level rise endangers the integrity of the entire South Floridian coast, Miami witnessed a ten percent population increase over the past decade. The Texas gulf coast offers another prime example. Though bombarded by hurricanes, extreme heat, coastal flooding, and more extreme weather patterns (i.e. the dramatic cold spell that paralyzed Texas earlier this year), an influx of migration has been a distinguishing characteristic of the region. 

The incongruous trend is the result of a myriad of intersecting factors — a housing crisis worsened by the COVID-19 pandemic, an aging population in search of warmth, exclusionary zoning laws, destructive federal land-use policies, and even flooding subsidies that counterintuitively encourage construction in fragile coastal ecosystems. 

The most vulnerable regions of the country are becoming more populous. And the sprawling nature of this population growth simultaneously worsens the root cause of urban climate change and magnifies the impacts of subsequent disaster. It’s a bipartite conundrum. How has federal policy expedited this phenomenon? And can bipartisan legislation improve urban sustainability before it’s too late?

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The age of urban sprawl was expedited by the rise of cheap oil. The accessibility of petroleum enabled the continued expansion of urban areas far from the true kernel of metropolitan zones, creating a culture of automobile use buttressed by the construction of car-centric infrastructure. Consequently, the modern city finds itself entirely dependent on the petroleum industry for subsistence. 

Detroit offers a textbook example of this phenomenon. In the wake of the population boom following the Second World War, Detroit sanctioned the creation of a kaleidoscopic web of ring roads extending outward from the city’s core. The aim was to suburbanize surrounding rural areas and accommodate a growing middle and upper class population.

In 2008, petroleum prices skyrocketed to record highs, stunting the economy of the city from the outside in. The low-density city model became rapidly unsustainable, and residents living far from the city center became the first to default on their mortgage payments and lose their homes. Of the 300,000 buildings in Detroit today, over 70,000 remain empty and in deteriorating condition.

Urban settlements are de-densifying by approximately two percent each year. The nebulous spillage of urbanity extends into valuable farmland and ecosystems, creating a patchwork of concrete and asphalt encroaching into distant terrain. 

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Low-density, sprawling city peripheries cannot be reconciled with a future in which urban life transcends petroleum dependence. But between 2001 and 2019, the built-up environment in the United States increased by 14,000 square miles across the contiguous United States — an area over five times the size of Delaware. 

A reimagining of federal and local zoning policies could be the first step in tackling the low-density city dilemma. Approximately 75 percent of land in most U.S. cities is zoned exclusively for detached single-family residential lots, eliminating the possibility of townhouses, apartment buildings, and duplexes. And in locations where higher-density residential housing is permitted, technicalities like minimum lot sizes and height restrictions often inhibit the potential for these spaces to truly transform housing. 

Increasing urban density near major transit and job centers can also help to limit petroleum dependency. Some U.S. cities have already begun to implement legislation targeted toward this objective. In 2016, Los Angeles introduced an initiative known as the Transit-Oriented Communities (TOC) Affordable Housing Incentive program. The program encourages affordable housing within a half-mile of major transit stops by permitting additional density in exchange for the creation of more affordable units, enabling developments to offset lost revenue through increased vertical growth. 

Economic evaluations have deemed the TOC project a relative success that could be emulated elsewhere. 

“The TOC programme successfully balances financial incentives that attract private construction of affordable units without giving developers a windfall,” said the lead author of the evaluation, Linna Zhu, a research associate with the Urban Institute. “While alone it won’t solve the housing crisis in Los Angeles, our study indicates that it is part of the solution and a roadmap for policymakers in other cities facing housing crises.”

Although only a small component of a multifaceted solution to a dual housing and climate crossroads, similar legislation in other cities could begin to address the predicament of rampant urban sprawl. 

At the federal level, infant legislation offers a glimmer of hope for bipartisan housing consensus. On March 23, Senator Amy Klobuchar (D-MN) introduced a bipartisan bill alongside Sen. Tim Kaine (D-VA) and Sen. Rob Portman (R-OH) called the Housing Supply and Affordability Act. The bill would provision $1.5 billion for federal grants to local governments to increase housing supply over the next five years. The bill is specifically designed to address the unique challenges of smaller cities over larger coastal hubs.

The policy may not be that straightforward in practice. Edward L. Glaeser, a notable housing economist, wrote an op-ed for the New York Times in which he discussed the idea that “a competitive grant program [such as Klobuchar’s] is too weak to overcome the entrenched interests — like the homeowners who control local zoning boards and the wealthy residents of cooperatives who oppose all neighborhood change — that limit building in productive places.” 

Glaeser claims that a housing plan should ensure that benefits only go to states that promote housing construction in high-wage, high-opportunity areas. Thus, combating repressive zoning and land-use laws at the local level would be the key to creating a greener future.

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An offshoot concern related to sprawling suburbs is the encroachment of residential areas into fragile environmental regions, which could lead to more climate disasters. Recent wildfires in the western half of the nation are a pertinent example. As the ill-defined fringes of cities bleed into new territory, residential zones pop along a tenuous boundary known as the Wildland-Urban Interface (WUI), where wildfires are more likely to occur.

According to recent studies, the WUI grew from 224,325 square miles to 297,299 square miles between 1990 and 2010 due to the construction of new homes. The most significant takeaway from the research: 43 percent of new homes are built on the WUI, even though the terrain only encompasses one tenth of the contiguous United States.

Fires are not the only problem. Urban encroachment also enhances the risk of mudslides, storm surge, and other precipitation-related concerns. Structures overtake floodplains and barrier islands that would otherwise shield civilization from an onslaught of hurricanes and intense storms.

And haphazard federal policies only exacerbate the situation. In 1968, a taxpayer-subsidized federal program called the National Flood Insurance Program was created to ensure that citizens received flood insurance even in regions deemed too risky by private insurers. But the program arguably had adverse effects — 2019 data reveals that the most flood-prone areas of certain states experienced the most construction growth. 

In 2012, Congress passed a bill intended to increase flood-insurance premiums to adequately reflect the risk of construction in vulnerable areas. Yet the legislation was reversed within two years when building industries pushed back.

In May, President Joe Biden issued an executive order requiring federal infrastructure projects to account for flooding risks prior to construction. The U.S. Securities and Exchange Commision (SEC) has also conceptualized a legal framework to require disclosure of climate risk from all public companies. Both of these initiatives could address the federal government’s role in encouraging flood zone construction, but the undercurrent of climate deception persists.

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The dilemmas of urban development, housing affordability, climate policy, and demographic change are challenging to tackle, and they are all interrelated. As urban megacities on the coasts become increasingly inaccessible and out-of-reach, the horizontal expansion of fledgling medium-sized cities appears inevitable. Americans are flocking to climate-threatened cities because they are cheaper and convenient. Not to mention, the pandemic is actively reshaping the nature of the true urban city — the rapid rise of work-from-home culture and the temporary suspension of bustling city life have prompted many to embrace the temptation of low-density environments.

Federal reform that facilitates higher-density residential areas and environmental protection from volatile ecosystems is at the center of combating the problem. The modern archetype of the budding American city is not sustainable in its current form. Legislative pathways are needed to curb the problem before it’s too late. The impending climate threat won’t wait.