Now more than ever, our cities need a bold vision that is backed by action.
The global Covid-19 pandemic has, for many, fundamentally changed our relationship to the outdoors. Even though green and public spaces have always been an important part of cities, multiple lockdowns have given us a new sense of just how important it is to get out of our homes and to be in contact with nature.
For some, green spaces in our cities became a safe place for us to be when we were feeling stressed, anxious or trapped. We discovered that being outside was one of the best things we could do to lift our mood and spirit. The sound of the wind in the trees, the smell of nature, even the rain on our faces — heading out for a walk or a bike ride allowed some city residents to reconnect with the wider world and our communities in a safe way.
Those moments have made many of us realise how critical green and public spaces are for our mental and physical well-being. We also realised how little access to good quality green and public space there is in most of our global cities.
Aside from the physical and mental health benefits provided by green spaces and trees in cities, they can also play a key role in mitigating the effects of environmental threats such as climate change and biodiversity loss — naturally cooling streets and homes, and providing precious habitat to local wildlife and insects.
Good practices in urban planning suggest that every resident should be able to see at least three trees from their home; cities should have 30% of canopy cover as a minimum at neighbourhood level; and people should find a green space at a maximum distance of 300 metres from their home. This is known as the 3-30-300 Rule. Applying this rule will improve and expand the local urban forest in many cities, and with that promote health, well-being, and resilience across increasingly populated global cities.
Things are improving. In the last 15 years the availability and accessibility of urban green spaces in 28 megacities worldwide increased respectively by 4.11% and 7.1%
However there is still a long way to go — only a handful of cities fully meet the World Health Organization recommendations on green-space availability that sets a minimum standard of 9m² per inhabitant. Ideally, this should be 50m² per capita.
It is not just us as residents who must be aware of the urgency and need to create greener cities. Mayors and local authorities must take responsibility for greening cities with fair and equal access for all, while leading an urgent ecological transition to tackle the climate and health crisis.
Here are seven reasons why we need greener cities now:
- Mental Health: Contact with green spaces is associated with lower risk of stress and psychiatric conditions such as depression and anxiety. There is growing evidence for the beneficial effects of green space on mental health linked to improvements in behavioural development.
- Brain Development & Cognitive Function: Long term exposure to green space can reduce the risk of behavioural and emotional problems and enhances cognitive development, including improved attention and working memory. Green space can play an especially crucial role in children’s brain and cognitive development.
- Other Non-communicable Diseases: Contact with green spaces is associated with lowered risk of cardiovascular conditions, diabetes, obesity and lower back pain. Considering that non-communicable diseases are responsible for the equivalent of 71% of all deaths globally, the global benefit of more accessible green spaces could be huge.
- Mortality: More green space in residential areas is associated with reduced all-cause premature mortality because of lower exposure to air pollution, people doing more physical activity, stronger perceived social engagement, and a reduced risk of depression.
- Pregnancy Outcomes: Access to green space is positively associated with increased length of gestation, reducing the risk of preterm birth, infant mortality, and negative long-time outcomes during childhood and beyond.
- Perceived General Health: More contact with green spaces has been consistently associated with an improved perception of general health and also subjective well-being — things like feeling more happiness and satisfaction with life.
- Reduced hospitalisation and recovery time: Exposure to green space helps to avoid hospitalization due to the development of healthier physical and psychological conditions, and reduces the recovery period after treatments and operations.
The ‘cherry on the cake’ is that not only are green spaces beneficial to our health and well-being, scientific discoveries, presented in our report Greening the City, have found that urban civic spaces, like squares, historical sites and panoramic points of view have similar health benefits as green parks do. We must preserve and introduce more green and civic spaces in cities — in ways that are accessible for all — to create liveable cities for future generations.
Celia Ojeda-Martínez, Chiara Campione and Alessandro Saccoccio work together in the international team leading the Greenpeace #HackYourCity campaign.