Parks, small woodlands and even simple patches of grass not only keep a city attractive, but also help
people find a sense of bliss in an otherwise bustling urban environment. With new technologies, we can
plan and monitor these urban “green spaces” better than ever before.
As several studies have highlighted, nature within urban settings plays a pivotal role in combating many
of the global public health challenges commonly associated with urbanisation. This includes maladies
such as depression and high blood pressure. A 2022 study showed that trees actually have the ability to
improve urban air quality as leaves and pine needles capture pollutants from the air.
That cities do need green spaces is therefore not a particularly contentious issue. It is, however, an open
question as to how much green space a city ought to have. Even here, science can provide some
guidelines, as research points to at least 9 square metres of green space per individual, with an ideal value
of 50 square metres per capita in a city (for comparison, an average UK car parking space takes up about
12 square metres).
The big question is therefore what kind of green space do we want? A well-kept but human-made park?
Or something more natural and unkempt, such as groves, meadows or field-like areas? As we discuss in
our forthcoming book, Designing Smart and Resilient Cities for a Post-Pandemic World: Metropandemic
Revolution, this is largely contingent on the geographic preconditions of the city in question. The World
Health Organization (WHO) recommends a diversity of different kinds of green areas if possible, yet it is
an inescapable fact that some cities are blessed with lush vegetation while others are not.
Our mission is to share knowledge and inform decisions.
However, all is not lost for cities without much natural green area, as such environments can be
constructed in urban settings that have previously been bereft of naturally growing trees and grass. This
“green landscaping” can be undertaken even in areas that would otherwise seem unlikely. One prime
example is the High Line in New York City, a 1.45 mile (2.33km) long elevated linear park built on an
abandoned railway viaduct. Since it opened in stages about a decade ago, the High Line has become an
exemplar of green landscape redesign that seeks to turn obsolete infrastructure into green, vibrant public
While it is known that greenery has positive effects on mankind at large, it is more difficult to prove the
exact causal relationship in exactly how green areas affect our health. In this regard, digital technology
can be an essential tool for urban planners to determine where green landscape redesign is best employed.
One concept that is seeing particularly rapid development is “smart urban forests”, which refers to using
tree monitors, 3D-imagery and other internet of things-linked technologies to help manage the forest. This
“internet of nature” could monitor soil health, measure air pollution or ensure urban forests are adequately
Future technology could also enable the use of open data platforms and more public engagement.
Planners could collect various perspectives from the general population using an app, for instance, while
also using digital technology to map and boost urban biodiversity and to ensure that green areas are
placed where they will achieve maximum efficiency.
One example of this is the Treepedia research initiative, which was launched in 2016 by Massachusetts-
based MIT Senseable City Lab. Treepedia aspires to raise awareness of urban forests by the use of digital vision techniques based on Google Street View images.
Treepedia calculates how much tree canopy is visible at various points on google street view.
Treepedia focuses on pedestrian street trees found in multiple cities around the world, as opposed to
parks. The main reason is that pedestrians are more likely to see street trees without planning to, whereas
most people in parks made an active choice to be there. Using an open-source library, Treepedia means
the public can calculate the quantities of tree coverage for their own city or region.
If urban planners become more aware of the potential of digital technology, then urban green spaces
should have a bright future. However, designing the optimal green space that we want for our cities may
also call for a deeper future collaboration between urban planners and engineers.