Philadelphia is a bit ahead of the curve in addressing the problem of climate change.

In 2019, the city’s Office of Sustainability launched the nation’s first and only city heat response plan, Beat the Heat, crafted through a planning process that reflected community voices. The plan includes a heat response checklist, ideas for cooling centers, and a design for a heat resilient neighborhood — all available for wide replication.

It is likely because of that plan and steps that had been implemented earlier — including the Hot Weather–Health Watch/Warning System that was put in place in 1995 — that the city’s heat-related deaths were five times lower during the 2010s than they had been during the 1990s.

In addition, this past summer Philadelphia was one of 16 U.S. cities to lead an Urban Heat Island Mapping Campaign, through a partnership between the National Oceanic and Atmospheric Administration and the Academy of Natural Sciences of Drexel University, to uncover the uneven distribution of extreme heat across the city’s neighborhoods.

Residents in Fairhill, Grays Ferry, and South Philadelphia have been engaged in public awareness campaigns, such as the innovative two-year neighborhood arts project Heat Response PHL, sponsored by the Trust for Public Land and the Pew Center for Arts and Heritage. The program underscored how extreme heat disproportionately affects low-income communities, and resulted in refurbished parks, children’s art projects, and a public awareness demonstration at the 2021 Philadelphia Flower Show.

» READ MORE: Summers are hotter, but heat-related deaths have dropped. Philadelphia has a lot do with that.

But Philadelphians — and everyone in the United States — should be taking more sustained, widespread action to avert, minimize, and address the effects of heat waves. A so-called silent killer, heat stress typically causes more deaths in a year than natural disasters, especially among older Americans, toddlers, pregnant women, people who regularly work outside, and those with chronic diseases.

The nation’s annual economic cost of lost labor productivity because of extreme heat is estimated at $100 billion. Heat can also damage and strain infrastructure, affect the delivery of public services, and reduce educational attainment. Evidence also exists of a direct correlation between violent crime and high temperatures.

There are numerous responses to extreme heat that Philadelphians can adopt, whether passively in reaction to heat waves, or proactively crafting and implementing heat-resilient designs writ large. These ideas come from a range of people and places: physicians at the Centers for Disease Control and Prevention, architects, landscape architects, city planners, real estate developers, industrialists, scientists, engineers, and grassroots housing advocates working in informal settlements.

So what more could Philadelphia do? The mayor could appoint a chief heat officer as have Miami-Dade, Phoenix, Los Angeles, Athens, Melbourne and Santiago de Chile, to raise awareness and integrate short- and long-term heat responses among city agencies.

Philadelphia could emulate Sevilla, Spain, and adopt a heat-wave naming protocol. (We name hurricanes, why not heat waves?) Philadelphia public and private decision-makers could join the Heat Action Platform to share knowledge on policy tools, financing mechanisms, and best practices for mitigating and adapting to extreme heat.

Philadelphia’s universities, philanthropic groups, and financial institutions could support heat-responsive projects. One can imagine a collaboration with the Pennsylvania Horticultural Society to scale up its greening activities.

These are just a few ideas, and surely Philadelphians have more. While thinking about heat waves as winter approaches might seem odd, the clock is ticking. Last summer’s record-breaking heat serves as a strong warning. It is time to reclaim and reinvent William Penn’s “greene Country Towne which will never be burnt, and always be wholesome” for the 21st century.

Mauricio Rodas is a visiting scholar at the University of Pennsylvania and senior adviser, Adrienne Arsht-Rockefeller Foundation Resilience Center. Eugénie L. Birch is the Nussdorf professor at the Weitzman School of Design and codirector, Penn Institute for Urban Research at the University of Pennsylvania.