What’s actually happening in the city ? When talking about the Anthropocene and about the future challenges, there are so many challenges and negative things we have to deal with. But I discovered when actually coming to the urban and the city there are also fantastic opportunities to solve these problems, and that is what really excites me.
We’re going to go through both some of the challenges because they are there, but also we’re going to particularly look at what are the opportunities here to solve some of these big problems we have had?
So talking about the challenges of course. Urban areas are expanding; more people live in cities than in rural areas in the world. And we also know that urban areas are expanding actually much faster than the urban population, and this is called urban sprawl. So we’re consuming a lot of land. And this is particularly worrisome because we’re also consuming a lot of prime agricultural land, which would then would have knockout effects on forests and savannahs and biodiversity in other areas.
So this is something we need to deal with. But urbanization is diverse. So we have on the one hand megacities we have by now around 30 megacities in the world with a population of more than 10 million. By 2030 we will have maybe fifty. So there is a huge expansion of these really large cities. But there is also another pattern that we need to think of, and that is the most of population growth in the world the next 20 years will happen in small and medium size cities. And there’s a lot of land that’s going to be consumed when these cities expand and grow. And that we should also not forget that in this diversity of urbanization we also have shrinking cities, and particularly in eastern Europe, parts of Japan, eastern North America, we can cities that actually are shrinking, they are losing population, and we have a city-to-city migration, which also opens up opportunities when it comes to biodiversity, ecosystem services and managing land.
So some of the key challenges are looking ahead with organization is that we will need more resources for a growing population, and also that when people move into cities they become more affluent, and they will increase their consumption of red meat, for example. So the dependence on land is going to increase. And just as an example, London today is requiring an area a 125 times the size of the city. And that’s the size of the UK’s entire productive land surface. And this dependence on land is going to increase and that’s why we need to understand and manage this is a way that we could actually have a sustainable production.
So the first point I want to make is that local governments need to address this land consumption and land management in a very active way in the future. And that’s one of the keys for sustainable development. And examples of what will happen when land is consumed is that urban areas will infringe into biodiversity hotspot areas, for example.
And just to take an example, 25% of the world’s protected area today are within 17 kilometers of a city. In 10 years it will be less than 15 kilometers. Data around this [has] been developed in a large global study called the Cities of Biodiversity Outlook, which was requested by the UN and looking at the challenges but also the opportunities. And Ban Ki-Moon writes in the preface of this study that as he viewed it the principal message is that urban areas must offer better stewardship of the ecosystems on which they rely.
And this is actually what we’re going to explore for the rest of this lecture on what are these opportunities and what does this stewardship actually mean? Because there are opportunities. Looking ahead until 2030 we could see that all the urban land we expect to have in 2030, 60% has yet to be built. There’s an enormous investment ahead of us for the next two decades in all types of infrastructure. And we need to get that investment right to get on a sustainable pathway for the planet.
And I would argue that this is the key for a sustainable planet, that we actually get urban development into a greening path. These investments are going to be made anyway. If we turn them into a green, more sustainable direction that’s the key. And we will show you some examples.
Humans living in urban areas are dependent on clean air, on clean water, food, and many resources. And urban ecosystems, the living world of urban area could actually promote and provide some of these benefits. These are called ecosystem services that could clean the air, help clean the water, and integrating living systems with a built environment in these ways I think open up fantastic opportunities to create urban areas that are livable, healthy, and prosperous, and would actually – are providing an environment for people that they enjoy and create a rich life, but also in a sustainable way.
So giving an example. One of the challenges we have ahead of us is of course climate change. And one of the most likely effects of climate change that would affect people is urban heat waves. We’re going to see a lot of these examples in the future where very hot temperature will prevail in cities. And just as an example the consequences of these are immense. In Europe we had a huge heat wave in 2003 and it’s estimated we had 70,000 excess deaths.
So how are we going to deal with urban heat waves? One way of doing it is actually to start planting trees in the city, because there is a very clear effect – cooling effect of trees. If you increase the canopy cover from 10 to 20% you would decrease the ambient temperature with anything between 3 and 8 degrees C, which is substantial.
And while you’re planting a tree in the city, you’re planting many, you would also get a lot of other benefits that are related to culture, to air cleaning, to reducing peak and precipitation, all other benefits. Which we just started to value and started to understand.
So here are lots of opportunities that combining the built environment with a living environment to actually address and solve a lot of these challenges we have ahead.
And just as an example where this is actually taking into action and implementation, Mexico City has launched a huge program where they will build 10 000 square meters of green roof to provide cooling, and regulate humidity, and also provide sites for biodiversity in Mexico City. And they also have a program for conserving land with the similar purpose of contribute to cooling the city and contribute to maintaining some of the very rich biodiversity in the city area.
And another important challenge when we look ahead is that we will have a growth of cities and a growth of population, but the average age, or the age of this growing urban population will be there will be young people. So the majority of people living in the world and in the cities in the future will be below the age of 20.
And there is a huge educational challenge here, but also opportunities. If we could find ways of engaging young people in managing, and restoring, and enjoying the living world in the urban area I think that’s one of the most fundamental keys for a sustainable pathway.
So just as an example of hundreds and hundreds of exciting projects going on around the world in cities, here’s one from New York City, in [the] Bronx where a group call themselves Rocking the Boat have engaged with disadvantaged kids in [the] Bronx and engaged them in restoring oyster banks and learning about the river, and how to clean up the river, how to create an environment in [the] Bronx that is actually beautiful which people would enjoy, and also learning about how nature actually could be an asset and something you could actually use in a very constructive, positive way to create a livable environment.
So my final message here is that cities have the unique potential to generate the innovation and governance tools that we need, and can and must take the lead in sustainable development. Most action in the world happens at the local scale. So if we could bring citizen NGOs, local governments together, with support from national governments, with support from regional government structures, like the European Union and others, and with support from the UN, I think there is so many things, so many exciting things, we could do at the local scale, where we could bring in already knowledge we have, and bring in new creativity and new thinking, new ideas to solve these problems. And I think it’s absolutely possible. It’s just that we have to come together, sit down and say we’ve got to do it. Thank you.
OpenEdition sugere que esta publicação seja citada da seguinte forma:
Pedro Pereira Leite (12 de Dezembro de 2015). Antropoceno XLI – Caminhos da Transição: novos caminhos das cidades. Global Heritages. Recuperado em 8 de Outubro de 2024 de https://doi.org/10.58079/p2x7