Environmental health researcher highlights how green spaces promote mental, physical, and environmental health.
In October, 2018, former Boston Mayor Marty Walsh and The Trust for Public Land declared the City of Boston had reached a major milestone in ensuring that all Boston residents have access to a public park within a 10-minute walk of home. The announcement stemmed from Boston’s championing of the 10-Minute Walk to a Park Campaign, a joint effort by the Trust for Public Land, National Recreation and Park Association, and Urban Land Institute. Their goal? Working to bring easy and equitable access to green spaces to everyone in the US, as data reveals just how crucial these spaces are for maintaining mental and physical health. But the initiative doesn’t stop in Boston. In fact, the collective ambition spans far outside the 617 area code, as leaders from over 130 different cities across the country have pledged their support since 2017. The need for this effort is now more urgent than ever: new data shows that the pandemic caused a surge in popularity for parks, and also further exposed disparities in who has access to them.
Boston University environmental health researcher Dr. Patrick Kinney has completed extensive work on the health, economic, environmental, and community benefits of urban green spaces. Trained as an air pollution epidemiologist at Harvard School of Public Health and recently named by Reuters as one of the world’s top climate scientists, Kinney is also developing a new program that focuses on assessing the health benefits of urban climate action plans, via strategies to promote active transport, green infrastructure, and clean vehicles at the Boston University School of Public Health. We spoke with him to learn more about the defining elements of green spaces, their impact on both city-scapes and city-dwellers, and how the COVID-19 pandemic has boosted their value.
How do you define urban green space? How do urban green spaces differ from urban green infrastructure?
Green space in cities can take many forms, including dedicated parks, street trees, private gardens, and corporate public spaces. The more specific term ‘green infrastructure’ usually, though not always, is used to describe landscape elements that incorporate vegetation as part of a system to control runoff of stormwater.
How important are green spaces and green infrastructure in urban environments?
Green spaces are essential features of high quality urban environments. On an individual level, they can provide cool, quiet and restorative areas of respite within an otherwise stressful urban landscape. On a larger scale, green vegetation pulls carbon out of the air, which helps slow climate change, while also cooling the local environment and reducing impacts of a warming world.
What are the benefits of access to green spaces in urban environments?
A large and growing epidemiologic literature documents a range of health benefits associated with living in close proximity to green space, including reduced overall mortality rates and cardiovascular diseases, and improved mental health. The mechanisms through which green space imparts health benefits remain the subject of active research, but likely include some or all of the following: psychological benefits including reduced stress; enhanced immune function; increased physical activity; social connectedness; improved air quality.
How has the COVID-19 pandemic affected people’s perceptions of green spaces?
Recent evidence has confirmed increases in recreational use of green spaces during the COVID-19 pandemic, which likely reflects several factors including time savings from not commuting, the relative ease of social distancing outdoors, and green spaces’ role as an antidote to ‘cabin fever.’ Along with improved air quality, this change in nature engagement may represent an important health benefit amid the otherwise devastating impacts of the COVID-19 pandemic.
Are there disparities in access to green spaces across cities?
A recent study reported that, across the US, low-income neighborhoods have 15 percent less tree cover and are nearly 3 degrees Fahrenheit hotter than high-income neighborhoods. These disparities were even higher in urban areas in the northeast US, with 30 percent less tree cover and 7 degrees Fahrenheit hotter temperatures in low-income neighborhoods. New green space availability data from The Trust for Public Land shows that across the 100 most populated US cities, there are major equity differences between population groups within each city. Neighborhoods that are majority nonwhite have, on average, access to 44 percent less park acreage than majority white neighborhoods. Furthermore, low-income communities in these cities have 42 percent less access to parks than high-income neighborhoods. Urban greening programs, if targeted properly, could help to alleviate these inequities, offering substantial health benefits.
Why should cities prioritize green infrastructure? How can it be effectively developed within existing urban spaces?
Cities are recognizing the need to prioritize green infrastructure — even if they are already widely developed. For example, here in Massachusetts Cambridge and Somerville are currently confronting the challenge of how to increase access to green space in areas that are already largely built out. Programs to plant new and maintain existing street trees can help. We also need more research to help planners understand which features of urban green space make them most effective in conferring health benefits. The High Line trail in New York serves as a strong example of a formally industrial space successfully converted into what is now one of the city’s most popular greenways. The former freight rail line breathes life into the surrounding community and adheres to a mission centered on reimagining the role public spaces have in creating connected, healthy neighborhoods and cities.
What are the factors that facilitate the execution of green spaces, and what are the barriers that may prevent such implementation in certain areas?
Greater public awareness of the health benefits of green space is one of the main factors that could help build political will for programs to invest in greening initiatives. One of the main barriers to increasing green space in urban areas is the lack of available space, thus calling for creativity in identifying vacant or convertible parcels. One innovative approach to consider is to convert obsolete car-centric infrastructure like roads, parking lots and shopping malls to mixed-use spaces that incorporate well-designed green space.