Why parks are key to helping cities fight back against climate change
From Jakarta to New York City, Dallas to Toronto, parks can help cities adapt to the worst effects of climate change. This is how
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ublic parks have historically provided cities with more communal and natural spaces. Now city planners believe they can serve an even more vital purpose – adapting to the effects of climate change.
From Jakarta to New York City, Dallas to Toronto, some of the world’s biggest cities are putting public parks at the centre of their climatechange adaptation strategies. Such green spaces not only provide some fresh air in areas prone to smog, but also help absorb floodwaters and cool down cities on dangerously hot days.
“City parks become critical infrastructure in a warming world,” explained urban planner and former Chief City Planner of Toronto, Jennifer Keesmaat. “Jane Jacobs called them the ‘lungs of the city’ 40 years ago, and that metaphor has stood the test of time. Grass and soil and other permeable surfaces are also critical for absorbing excess water, and collecting it at the source.”
Managing the threat of heat and water
Ms. Keesmaat explains that parks can serve a wide range of important purposes for cities struggling with the effects of climate change.
“We know that unprecedented levels of water are entering our cities, damaging homes and critical infrastructure—like transit systems and roads,” she said. “But trees are a part of the solution, given that they both provide desperately needed shade alongside city streets, and absorb C02 from the air.”
A 2018 study by the National Oceanic and Atmospheric Administration confirmed that urban density is a significant contributing factor to extreme heat, as surfaces like asphalt and concrete amplify its effects. The study found a roughly 9 degrees Celsius discrepancy in average temperatures between more densely populated areas in Baltimore and Washington as compared with less dense neighborhoods that featured more trees and public parks.
“Major roadways and dense urban pockets are some of the warmest landscapes in both cities,” reported researcher Jeremy Hoffman of the Science Museum of Virginia. “These are areas with little or no vegetation, more asphalt and concrete buildings, which can amplify a heat wave.”
Reducing heat can be a lifesaver, as more than 600 deaths are caused by heat-related illness worldwide each year. The damage caused by flooding is also on the rise in the United States; the number of flood-related deaths grew from an average of 86 per year over the past 30 years to more than 100 annually each year since 2015, according to a study by the Weather Channel.
A few major cities are leading the way
Fortunately, many cities around the world have identified the vital role public parks play in helping citizens adapt to the effects of extreme heat and flooding, and are investing in expanding their presence in major urban centers.
Chicago’s Space to Grow program, for example, seeks to transform local schoolyards into functioning outdoor activity spaces that also help reduce the effects of flooding in low-income neighborhoods. They incorporate landscape features that capture a significant amount of rainfall in order to help keep the city’s water resources clean while reducing the potential for neighbourhood flooding.
Flooding has long been a dangerous problem in Indonesia’s most densely populated city, but in recent years Jakarta has invested in increasing public parks in order to improve resilience against floodwaters for the city’s 10 million residents. The city plans to increase green spaces from 10% of city lands to 30% by the year 2030 in the hopes of significantly reducing flood duration and damage.
Similar projects are currently underway in other major cities around the world—including Houston, Atlanta, Boston, New York City and Toronto—and more heat and flood-prone cities are likely to join the growing list in the coming years.
“Green spaces were once valued primarily for their recreational benefits, and the reprieve that they provide from urban living,” explained Keesmaat. “Today their ecological functions are rising to the foreground as essential to both mitigating and adapting to climate change.”
The ideas presented in this article aim to inspire adaptation action – they are the views of the author and do not necessarily reflect those of the Global Center on Adaptation.
