Urban greenery can cool warming cities, and make us happy, too

The Bosco Verticale (Vertical Forest), Milan. Image: Getty.

The current climate and ecological crisis demands a radical redesign of how we live and organise our societies. Yet these urgent changes, though complex, are far from impossible.

Some of them are simple, beautiful, and beneficial to all. By greening our cities with street trees, urban parks, and community and rooftop gardens, we can keep ourselves cool amid rising temperatures, reverse the steady erosion of the rich tapestry of life on Earth, and foster happiness and social connection in the process.

It is widely known that greenery in urban spaces helps improve city microclimates. Thanks to heat generated by traffic and industrial activity, as well as the spread of heat-trapping concrete buildings that have steadily replaced plant life, urban air temperature is often higher than in rural environments. Hotter cities compel urban denizens to opt for air conditioners in order to stay cool, which further strains energy demands and worsens the urban heat island effect.

Plants can help cool cities through the water that evaporates from their leaves when exposed to the sun’s rays, and by shading surfaces that otherwise might have absorbed heat. Research has found that on a sunny day, a single healthy tree can have the cooling power of more than ten air-conditioning units.

Plants also help keep harmful pollutants such as microscopic particulate matter at bay through a complex process known as dry deposition, whereby particles penetrate and become trapped in the wax or cuticles of leaves. Although banning or at least restricting vehicle use in city centres is crucial, mass greening can further reduce pollution and keep cities cool in the increasingly scorching summers that lie ahead.

Urban greenery wouldn’t just help lessen the impacts of climate change and improve air quality. Evidence from a range of disciplines has uncovered numerous social, psychological, and health benefits of human exposure to green spaces. These include stress and anxiety reduction, improved cognitive functioning, lowered risks of depression, and overall greater mental and physical wellbeing.

Others have shown how involvement in community gardening can increase social cohesion and social bonds among participants and the wider community, in addition to providing local and affordable food sources.


The Japanese preventative healthcare practice of Shinrin-yoku, or “forest bathing”, is modelled on a recognition of the many benefits of immersion in natural spaces. We’re not yet sure why we seem happiest and healthiest when we’re surrounded by our fellow lifeforms. But the universality and antiquity of our appreciation for nature suggests that our biophilia may originate from the millions of years humans and plants spent co-evolving in close contact with each other.

Perhaps most importantly, greening and rewilding our cities can offer vital refuges for rapidly vanishing biodiversity. Human socioeconomic activities, especially those of the world’s rich, have destroyed natural habitats, consumed vast tracts of forest, polluted waterways, and disrupted the seasonal rhythms on which life depends. In the midst of the sixth mass extinction, many species are increasingly finding themselves with nowhere to go.

Urban rewilding can help the complex natural communities and processes that are essential for all life to flourish once again. For example, establishing wild meadows and native plant and tree communities provides pollinators and other threatened animals with new spaces to thrive, while creating spaces to reintroduce keystone species, whose presence is crucial for maintaining ecosystem diversity.

Towards a thriving future

The mass greening and rewilding of our cities is no novel or abstract ideal. It is already happening in many urban spaces around the world. The mayor of Paris has ambitious plans to “green” 100 hectares of the city by 2020. London mayor Sadiq Khan hopes to make London the world’s first “National Park City” through mass tree planting and park restoration, greening more than half of the capital by 2050.

Singapore, a partner city in the Biophilic Cities Network, is a shining example of how to incorporate “nature” into building and city designs. The Parkroyal on Pickering Hotel, for instance, is shrouded in thickly forested terraces and sky gardens that are inhabited by local insects and birds.

More cities need to follow the lead of these forward-thinking designs and initiatives. Alongside these efforts, educational programmes, such as Singapore’s Community in Nature initiative, could also be put in place to help the public learn about, respect, and appreciate wild spaces.

Of course, urban greening alone will not be enough to meet the daunting challenges ahead. We also need to fundamentally transform our growth-oriented economies and massively reduce global inequality. But giving some new life to our cities would be a great start. And it wouldn’t just benefit people but, crucially, other species as well. This is their home, too, and they deserve a more viable future.

The Conversation

Heather Alberro, Associate Lecturer/PhD Candidate in Political Ecology, Nottingham Trent University.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

 
 
 
 

Jane Jacobs and Le Corbusier would agree on one thing: we need more social housing

Unite d’Habitation, Marseille. Image: Iantomferry/Wikimedia Commons.

Much has been written in CityMetric and beyond about the urban planning debates of the 1950s and ‘60s, that came to be characterised as a battle between master-planning and preservation. One side of the debate was personified by the father of modernist architecture, Le Corbusier, whilst the counter-argument was advanced by writer and journalist Jane Jacobs.

But when it comes to London’s housing crisis, aren’t there a few things that these two would actually agree on?

Jane Jacobs’ writing about the organic nature of self-organising communities, demonstrated, in her words, by the “intricate sidewalk ballet” of inner city neighbourhoods, should be required reading for anyone interested in how cities function. But today, Jacobs is increasingly invoked in attempts to oppose new developments of any kind. Her role in conceiving Manhattan’s West Village Houses, a low cost rented housing scheme built through New York State’s Mitchell-Lama Program, is unfortunately much less well known. It’s been suggested that if Jacobs were around today, she’d be working with New York’s housing activists. When her seminal work The Death and Life of Great American Cities was written, there were almost 2 million rent-controlled or rent-stabilised apartments in New York City; nowadays, there are fewer than half that number.

Le Corbusier, on the other hand, is too often blamed for drab high-rise blocks. But regardless of how well his followers across Europe interpreted his ideas, Le Corbusier’s vision for cities was about high quality residential blocks that also contained shops and leisure amenities and were surrounded by parkland – the original mixed use development if you like. His most famous building, Marseille’s Unite d’Habitation, consisted of 337 apartments with views of the mountains and the sea together with shops, a restaurant and a nursery school. The building was originally intended to be public housing, but the French government eventually sold off the flats to recoup costs. Alton West Estate in Roehampton and Park Hill in Sheffield are just some of the examples of Le Corbusier’s influence on the design of post-war council housing here in the UK.

Building homes for a serious business in post-war Britain. Under Attlee’s 1945 Labour Government, 700,000 new council homes were completed. In 1952, the largest architectural practice in the World was at London County Council, with 1,577 staff including 350 professional architects and trainees. These were the days of consensus, and very quickly Tory governments were actually competing with Labour governments about who could built the most council homes.

Some of the council homes built post-war have stood the test of time better than others. But what’s not in doubt is that building council homes on such a scale immeasurably changed the lives of so many families in desperate need of a decent, secure and affordable home. And so many of the post-war modernist high-rise blocks so despised by Jacobs quickly took on the organic self-organising traits that she held in such high regard and have become some of the most enduring and closely-knit communities in London.

Fast forward to 2019 and Right To Buy continues to decimate council housing stock, but perversely home ownership seems more out of reach than ever for so many. An entire generation is being forced to embrace long term private ting in a country that has some weakest protections for private tenants in Europe. Meanwhile, government spending on building new homes fell from £11.4bn in 2009 to just £5.3bn in 2015 – from 0.7 per cent to 0.2 per cent of GDP – and since then, the housing minister’s desk has been occupied by no fewer than six people.


So what would a comprehensive drive for new council and social housing on the scale of the 1945 government’s efforts look like in 2019?

Lubetkin, the architect responsible for Islington’s Spa Green Estate and Bevin Court, summed up the spirit of post-war council home building with his maxim that “nothing is too good for ordinary people”. It’s a vision that we’re trying to recreate through our own council home building programme in Islington.

One of the best opportunities for small council home building schemes is to expand upon existing communities. The vast majority of Islington’s new council housing takes the form of infill, construction on existing estates; in unloved spaces, in old garages, and in old undercrofts. These projects often involve landscaping and new amenities to enhance rather than reinvent local communities. We have built community centres and even rebuilt a library as part of council housing schemes. One Tenants’ and Residents’ Association had an idea for a new specialist over 55s block for the older residents of the estate who wanted to stay in their community.

But there’s a place for large-scale place making as well. When the Ministry of Justice closed Holloway Prison and announced that the site would be sold, Islington Council published a Supplementary Planning Document (SPD) on the site. We had one aim – to send a clear signal to the market that anyone who was looking at buying the site needed to be aware of their planning obligations. Most importantly, any development on the site needed to include at least 50 per cent genuinely affordable homes. The speculation around the site came to an end on 8 March this year when Peabody Housing Association announced that it had bought it. It has committed to going well above and beyond our planning requirements, by making 600 out of a total 1000 homes genuinely affordable homes, including 420 homes for social rent. We need to see more detail on what they are proposing but this is potentially brilliant for the borough. A local grassroots group, Community Plan for Holloway, have been instrumental in ensuring that the community’s voice is heard since the site was sold.

To recreate the scale of the massive post-war council home building programmes would require a Jane Jacobs inspired level of community activism combined with the architectural idealism of Le Corbusier. But it would also need the political will from central government to help local authorities get council housing built. And that, sadly, feels as far away as ever.

Diarmaid Ward is a Labour councillor and the executive member for housing & development at the London Borough of Islington.