Cities at the frontier of sustainability: insights from the Global Cities Index 2025 | Greenomics podcast

Jake Kuyer:
Welcome to Greenomics. I’m Jake Kuyer and I will be hosting this episode. I’m an associate director with Oxford Economics, specialising in environmental economics and the application of economics to various sustainability challenges. Today’s episode is on sustainable cities and the new Global Cities Index that Oxford Economics has recently released. I’m going to start off by reading from a blog that one of our colleagues, Daniel Parker, has recently written, and I think it gives a good framing for the questions that we’re going to get into today.

The world has witnessed unprecedented urban growth in recent decades. In 2024, third of the global population was represented by the 1000 major cities considered in Oxford Economics global cities service. A striking testament to the size and importance of these urban centres. But while urbanisation offers significant opportunities such as economic development, innovation and improved connectivity, it also presents challenges. These include mounting pressures on public services, increased demand for infrastructure and, in some cases, the proliferation of unplanned and or unsafe urban expansion. Given their scale and density, urban areas are also amongst the largest contributors to climate change. Cities produce up to 70% of global greenhouse gas emissions, despite only covering 2% of the Earth’s surface. This highlights their paradoxical position, they drive environmental degradation, but are also among its most vulnerable victims, facing rising temperatures, air pollution and more frequent climate related disasters. For some, these issues are further compounded by their urban heat island effect, making cities even hotter and more hazardous.

With that, I will introduce you to our guest for today’s discussion. My colleague from our Cities and Regions team, Anthony Bernard-Sasges, Anthony is a senior economist on our Cities and Regions team, and I will hand it over to him to properly introduce himself – Over to you, Anthony.

Anthony Bernard:
Thanks, Jake, and thanks for having me on today. As Jake mentioned, my name is Anthony. I’m a senior economist on the Cities and Regions team here at Oxford Economics. I primarily focus on forecasting the US and Canada, but I’m also one of the lead authors and creators of the Global Cities Index. Happy to chat about it today.

Jake Kuyer:
Great. So let’s jump into it. Firstly, could you tell us a bit about how the index has come about? It’s actually proven to be a very popular story for Oxford Economics. People are inherently interested in cities and also in rankings. But what’s it what is its ultimate purpose? And what can people do with these rankings and data?

Anthony Bernard:
Yeah, you sort of hit the nail on the head there. It’s, you know, these sorts of rankings and lists of cities are very, very popular with people. And so we we have created this index based on the global cities service we have at Oxford Economics, where we have forecasts and data for the thousand largest cities in the world, covering a range of different indicators like labour market indicators, economic growth indicators, demographic indicators, etc.. And we decided to combine this sort of best in class economic forecasting we have with additional external data sets, things related to the climate, things related to governance, metrics related to quality of life and put all of this together to create, a ranking of the thousand largest cities in the world. So, like you said, you know, this is something that has gathered a lot of attention. And I think it’s potentially because we have, as far as I can tell, having done some background research on the other indices that are out there and what’s covered by, by other organisations. We think we have one of the most comprehensive rankings and indices here where we cover indicators across a range of different categories, looking at things like economics and human capital, but also things related to quality of life and the environment and governance. And we do this for, you know, like I said, the thousand largest cities in the world. And so ultimately, we put together this comprehensive ranking of these cities, which I think is interesting in its own right. But I think the value in this, in this index lies beyond just what the top cities are, because I think we could, you know, discuss and argue to the ends of the earth which city should be on top, which one should be lower? You always sort of have these different discussions and everybody will rank city slightly differently. But I think the value is in being able to identify, you know, the strengths and weaknesses for different cities around the world across a range of metrics. So we’re not just talking about cities that are strong economically. We’re also talking about cities that have you know, very good human capital pools, cities that have, you know, a very high quality of life standards or cities that have, you know, very strong environmental, backbones or potentially the opposite of that, cities that maybe are struggling economically or are lacking for, you know, are facing demographic challenges or are facing sustainability and climate change issues.

Jake Kuyer:
Great. Thanks. So it sounds very comprehensive. You’ve run through many of the metrics that, go in and the different categories that you look at. One thing I’m interested in having put together, indices myself over the years is that it’s not just a matter of choosing, a comprehensive set of metrics, but it’s also how the metrics are treated within the index. So how much influence they have over the overall rankings. And that can take a little bit more, thought than just putting the numbers together and pulling out some, some basic inferences. I wonder if you could talk a bit more about that. So sort of how different metrics can influence the results, but also if any consideration was taking taken to, to some of the broader context, things like how GDP per capita might actually influence, a city’s ability to how it performs sustainably, otherwise, and I could be wrong here, but I’d assume that the index might tend to favour cities in more advanced economies. Is that the case? Is that something that that’s been taken into consideration?

Anthony Bernard:
Yeah, that’s a that’s a really good question and something that we’ve had to grapple with in the creation of this index. The first point I’d make is because this is so comprehensive, covering a thousand cities around the world. One of the first challenges we faced was, you know, gathering data for all of these places, making sure that any indicator we do include really does have to exist for all thousand cities around the world. So it has to exist for both, you know, the, you know, large international hubs of New York and London, as well as much smaller, you know, regional capitals in Southern Asia, in the US and Canada, in Latin America and Eastern Europe, all over the world. So we found that it was very quickly apparent that there were a lot of indicators that we would have loved to include, but on a global scale, it was very difficult to get consistent data. Everything we do have in the index is globally consistent for all thousand of these cities, which I think gives it that value. To your point about the importance of the different indicators and what we can include. I think that ultimately led us to like looking at the, importance and the weightings of each of these indicators through a couple of different lenses.
The first is, as I mentioned, just, you know, data availability. You know, if this was something that we couldn’t find everywhere we just didn’t include it. We didn’t feel like it would make sense to bias certain indicators towards certain regions to the point that you made. Then we were also looking at what other indices have included in their rankings. So ones that look at liveability, what do they include? Do they talk about access to leisure? And a lot of them do. And so we’ve included some metrics on that, ones that look at, you know, human capital. We’re talking about the sort of the age profile of the cities, but also population growth, you know, is there a are the cities maintaining their size that they’re continuing to grow? Things related to economics and, and environment follow a similar path where we’re trying to cover a relatively wide scope of what these indicators could mean in the environmental category. For example, we look at both things related to the direct impacts of climate change, things like, natural disaster intensity and frequency, things related to, you know, heatwaves and droughts. But we also look at maybe the more, I guess, for lack of a better word, like policymaking, relevant side of things. You look at, like emissions intensity and we look at air quality, some of the things that, have a little bit more of an impact down the line from, from the direct impacts of climate change. So it was difficult to identify all of these in the first place, but then it was sort of slotting them into the correct categories and deciding, you know, which of these do we think are most important to the economics pillar, to the environmental pillar?

What have other, indices included in their rankings? And to your question about, you know, how are taking into account things like GDP per capita and stuff like that. In general I would say the top cities in the index tend to be in more advanced economies, but I don’t think that’s necessarily just a result of, you know, they’re having higher GDPs per capita than elsewhere. They we do, in fact take into account GDP per capita in the index. But we also look at things like GDP growth and in GDP growth. The fastest growing cities in the world are definitely not an advanced economies. They tend to be in Southern Asia or sub-Saharan Africa, where these economies are expanding very, very rapidly. And so depending on the indicator, you look at, you’re not necessarily just getting advanced economies coming out on top. We get a relatively even spread of that. And in the environmental category, actually, that’s maybe a good example of this, where some of the top cities in the environmental category aren’t necessarily the ones that are in advanced economies. In many cases, they’re happened to be in locations that don’t suffer as much from temperature anomalies or rainfall anomalies, or they tend to be a little bit more sheltered from natural disasters. And so I think the fact that we have this, this breadth of coverage of indicators means that we can we can identify the strengths of cities in developing countries as well, not just bias towards advanced economies.

Jake Kuyer:
Right, okay. That’s a good amount of detail and context on the thinking behind the index and how it comes together. But let’s get into the fun part then. So the actual results and rankings, could you talk us through some of the top performers, maybe the top three or top five? And I’m also curious as to whether there was any surprising results in the overall ranking. So maybe things that were not quite what you might have expected going into it.

Anthony Bernard:
Yeah. The top cities this year, are maybe not surprisingly, but the same as the top ones from last year. So the top two cities are New York and London, which was the case last year. These cities are very, very neck and neck at the top of our rankings. They tend to perform very well in terms of economics and quality of life. I don’t know that that’s necessarily surprising either. I think oftentimes when you look at these sorts of rankings of cities around the world, the New York’s and the London’s tend to be at the top or near the top. And so, you know, this just sort of shows that even when you sort of have a holistic consideration of 27 different indicators and look at a thousand cities, these cities do still tend to come out on top. Rounding out the top five are Paris, San Jose and Seattle. And so again, these are some of the more developed cities, more established cities in the US and Western Europe. But when we take a bit, maybe a bit of a larger look, zoom out a little bit at the top hundred cities in the world, we have about I think there’s around 40 in North America, around 40 in Europe, around 15 in Asia Pacific, and about five in the Middle East. So there’s obviously some regional variability, not a ton. It is dominated by North America. And Western Europe. But I would also say that they’re not necessarily at the top for the same reasons, which is maybe interesting. We find that a lot of the North American cities tend to perform best in the economics category, while their European counterparts are stronger performers and quality of life and environment. And I think that’s probably the case with what you would sort of hear and expect around sort of anecdotal evidence or the narratives around these sorts of cities. US cities tend to grow very quickly for being developed cities. They have very, very large economies. They have high GDP per capita, but they may not have the same, quality of life amenities or standards that a lot of European cities have. And European cities tend to be the ones with, you know, slightly higher life expectancy. They tend to have more amenities per capita. They tend to have more income inequality tend to have, you know, better environmental scores. And so I think that is sort of borne out in the data, which is again, maybe not unexpected, but I think is a good sign to showcase that the fact that we cover this many cities and, and have this much data, we are getting some of the results that we might expect from hearing anecdotally.

Jake Kuyer:
Yeah, I think that makes sense. I’m wondering if you can talk us through the results on some of the environmental, metrics, how those cities or others have performed?

Anthony Bernard:
Yeah, absolutely. I think the environmental category is one of the most interesting ones in the index, mostly because we have two different kinds of indicators in this. I’ve sort of alluded to this before, where you have some indicators that aren’t really in the control of the city at all. Right. So there’s not much a city can do about its whether or not it is at risk of severe natural disasters or whether or not faces heat waves or droughts. That’s sort of just a sort of condition of where the city is located geographically. But at the same time, some of the other indicators we include in this category, things like air quality and emissions intensity, is directly related to, you know, different policies that the city can enact. And so I think this is a really interesting place to look, because some of the top cities in the environment category and some of the cities that we have identified as sustainable cities. So what you read at the start of the this episode, talking about that blog was sort of us teeing up this concept of sustainable cities that we’ve analysed this year. These are cities that tend to perform very well in the environment category, and they’re not just cities in advanced economies. They’re not just cities in Western Europe. Of course, there are many that are in Western Europe. There are many that are, you know, the ones you would expect to the Nordic cities do very well in this category because they simultaneously aren’t quite as exposed to some climate risks and also have done a lot in terms of, emissions intensity and improving air quality. While some of the other cities that are at the top of this list are maybe at the top of the list because they don’t have much of an alternative, we find, interestingly, a couple of island nation capitals that do very well in this category. And so these cities are what we’re calling sustainable cities because they’re facing these sort of immediate risks related to climate change. Right? Sea level rise, increased flooding, increased hurricanes or typhoons. And these are cities that for that reason, are making important strides in the sustainability space. And so cities like NASA out here is a good example. Suva, capital of Fiji, is also one of the top cities in the environment category. And these this is where you sort of get a little bit of that divergence, where the sort of more developed Western European capitals taking the lead on, you know, being able to transition away from dirty fossil fuels because they are, able to make those economic gains while some of the other cities in the space are leading because they don’t have much, they don’t have much of a choice to maintain the sustainability of their city in the long run.

Jake Kuyer:
Yeah, really interesting stuff. I’m sure lots of listeners will want to, dig into the results a bit more of them themselves. And we’ll point to the direction to, to find the index at the end of the episode. I want to move a little bit beyond the index itself. For the next question. And again, you’ve touched on this a bit already, but just to focus a bit more on what actually makes a city sustainable and what would the aspiration be? Ultimately the index helps to kind of measure and put some context around these issues. But the purpose is probably more about shining a light. Onto these types of issues that cities can start to become more sustainable and start to address some of these things. So how would you define that in, in practice? Is it about reducing negative impacts? Is it about managing risk? Is it about being aware of and taking control of a city’s carbon footprint or material footprint or any thoughts around what actions the city might take?

Anthony Bernard:
I think it’s a little bit of all of that, really. I mean, I know it’s the least fun answer is, you know, a little bit of everything. But I do think that obviously there are multiple lenses with which, like city sustainability needs to be, you know, it needs to be analysed and, you know, the goals for cities in terms of being sustainable need to meet several thresholds and these different criteria, like you mentioned, you know, one of them might just be, you know, that sort of risk mitigation and management, as we’ve talked about, you know, there isn’t a ton that cities can do when being in a location that puts them at a higher risk of natural disasters. So whether that is, you know, increased flooding or, wildfires or whatever that may be there, there needs to be some sort of climate adaptation and mitigation put in place for those areas in. On the flip side, there’s also, you know, that sort of maybe, emissions side of things where there’s that transition towards net zero. There’s that, investment in renewable energy, investment in improving the grid in a lot of locations. I think there’s those two main factors. And they’re not always, maybe they’re not always working hand in hand, but they need to be sort of accomplished simultaneously. I think the third component that I want to call out as well as is maybe more of an economic focus where, you know, we talk about a lot of a lot of cities around the world, you know, having green jobs or a green economy. And like, what does that mean in a practical standpoint? It means moving away from dirty manufacturing and, and extraction of fossil fuels. Well, that’s fine in theory. But in practice oftentimes the issues we run into is, you know, the jobs that are lost for moving away from those industries aren’t as easily gained in the same location or with the same skill sets for the green economy. So cities need to sort of strike that balance of a moving forward while simultaneously, you know, allowing the population and the labour market to stay healthy. And there’s that lens of sustainability as well. It’s not just, climate sustainability. It’s also sort of an economic sustainability, a sustainable development of the city that needs to be that needs to be managed.

Jake Kuyer:
Yeah, absolutely. I often talk about that when, when I’m talking about sustainability, that that’s not just environment and climate. There’s also social sustainability. And economic sustainability is also part of the puzzle. And really sustainability is keeping the different elements in balance. And I do wonder within the index if some if there’s a, if there’s a relationship between some metrics which might push a city up the overall rankings, but might actually be inversely related to their performance on environmental metrics. So I’m thinking about some types of economic growth or population growth which might make a city, overall, higher performing, but might also have consequences on things like air pollution or, you know, congestion and various other issues. So again, things don’t always move in the same direction and it can be quite complicated. So a lot of it must be around maintaining a balance. On that I’ll move into, I think, a final question. And it’s kind of around becoming sustainable, but also managing a city’s overall performance and keeping this balance. What types of specific opportunities and challenges for cities, do you think could be addressed? What are some practical next steps? Perhaps, is a better way to phrase that that could be undertaken following on from this research. And also who is the ultimately responsible? Is it city governments? Is it national governments? Perhaps businesses in the private sectors, civil society and everyday residents? Yeah. Any thoughts on that? Or if there’s any examples you could give?

Anthony Bernard:
Yeah. I mean, I think, you know, the practical next steps from this I think is, is one of the main, the main points of value from the index is it’s not just like I said before, you know, comparing a city A to city B and seeing which one comes out on top, it’s identifying areas of weakness for all these cities.
Even the New York’s and London’s at the top of the index still have relative strengths and weaknesses. And I think it’s identifying those weaknesses, especially in terms of sustainability. That is a very important point here. I will use New York as an example because I think it’s a it’s a good one at the moment where, you know, New York is the top city in the world currently for, for our index. But it’s certainly not the top city in the environmental category, despite it doing relatively well. But we sort of expect that cities score to improve next year in environment because of the policy they put in place. Related to the congestion pricing in Manhattan. Now, that’s I think, a very interesting, example, because it shows the sort of direct impact that policymaking can have. There are certain characteristics or certain metrics in the index, like I’ve mentioned before, that are a bit harder to influence directly through policymaking. But there are others like air quality, that can be directly impacted. And so we fully expect New York’s score in terms of air quality to improve next year, because there’s already evidence that’s come out that this congestion pricing plan has reduced, you know, car traffic in Midtown in lower Manhattan and has sort of improved the air quality in that region. And so I think that’s maybe one example of how, you know, some of these specific challenges can be addressed. Like you mentioned, there is this trade off that like, especially for a lot of cities in the developing world that are growing rapidly, that are developing rapidly, they’re facing issues related to urbanisation, whether that’s not enough transportation infrastructure, whether that’s not enough housing infrastructure. And that leads to a lot of issues that go beyond, just, say, the economics category that bleed into sustainability and being able to address those directly with sort of sustainable city planning will play a major role in how those cities do in the long run. I think the responsibility of all these things, there’s several stakeholders that that are that play a major role in this process. You’ve mentioned them. They’re right that the national governments, city governments, the private sector, obviously, civil society and the residents of these cities are the ones that will ultimately be benefiting from this and experiencing this on a daily basis. But I do think that it starts with incentives that are put in place by the national and local governments. And I recently spoke to someone on my team who comes from a government background about this topic, how governments need to sort of play a key and leading role in this space, because they’re the ones that can sort of set up, improvements on the challenges that cities are facing in the sustainability space.

Anthony Bernard:
Hi Liam, I wanted to chat a bit more about sustainable economic development, and specifically about how national and local governments play such a key role in this process. I think, from a government background yourself, can you talk a little bit about the opportunities and the challenges that you see for cities in this space and the role that the government plays in all of this?

Liam Sides:
Thank you. Today, to introduce myself, I’m Liam Sides, associate director for global Cities analysis here at Oxford Economics, and I have recently joined from the UK government, where I led UK regional policy development and analysis. In this sustainable development objectives were absolutely central to decision making. So to jump to it, sustainable economic development isn’t something new and it’s been around in various guises since the start of the Industrial Revolution. Many of the key features of the UK today are the outcome of policy making, prioritising sustainability and in the face of a warming climate and an increased frequency of extreme weather events. The importance of sustainable development has only gathered pace. It’s why we see the government promoting the net zero transition, and it’s why we see a country throwing at wind turbines and solar farms and the UK really is a world leader in this space. I mean, renewable energy sources account for over 40% of UK energy production, up from 15% in 2015 and from just 2% in 1990. This has enabled the UK to actually phase out coal as part of the energy mix permanently, and that’s after 150 years have been a vital element. So the UK is well on its way through the net zero transition, and big changes are occurring. And the importance of sustainable development is not going away either. And that can be seen in the, in that one of the governments five missions for this Parliament is to make Britain a clean energy superpower, continuing that increase of the share renewables in the energy mix and creating jobs to service the new economy. For many, sustainable development is a no brainer, and often the debate is highly optimistic, with a focus about almost entirely on the new jobs that can be created and better living standards that everyone can enjoy. And I mean, it’s easy to see why cleaner air, reduced emissions, new jobs. But for policymakers, there’s an increasing concern that the significant focus on the benefits is leading to a downplaying of the very real challenges the transition throws up, particularly at the subnational level, and a core issue that I personally have to think about, when considering UK regional development, was the changing jobs and skills market as we move towards a net zero economy. This is because green jobs are not necessarily going to be where the brown jobs are currently located, nor are the jobs replacing them necessarily require the same skills or going to be paying the same wages. So what do I mean by this? Well, first, on the location of jobs, studies on green jobs point to them being highly urban. This is in contrast to the brown jobs of today, which are disproportionately located in rural and largely deprived areas of the UK. Policymakers need to think more about how those losing jobs in dirty industries can access the green jobs of tomorrow, and also understand what the implications of a yet more urban and potentially even more service based economy might mean for the UK’s economic geography and for investment.

Second, on pay and skills. Many brown jobs pay above average wages and for skills that aren’t necessarily transferable or formal. Let’s take steelworkers, for example, one of the most carbon intensive industries in the UK and an industry in which steelworkers have significantly higher wages than the local and regional average. Yeah, the formal qualifications are limited, the regional labour market relatively weak, and the green jobs available relatively lower paying and not necessarily in the area. They serve up a huge challenge for policy makers. How do we upskill people already? Well on their on their way in their career, how to meet relatively high wage expectations. Adding to that, that these people will likely have to move for similar paying jobs and you have a significant social cost within a place that the government has today, has to deal with. Overall, though, a sustainable development is hard, but it’s worth it to build a society for the future. One thing that’s for certain, though, is that governments have to do more to manage this transition. They have to spell out the benefits better, and they have to ensure that the costs are limited. And there’s no reason why the UK and other countries can’t do more to support upskilling, benefit those communities that are most impacted, and ensure that people feel the benefits in that pocket economically as well.

Anthony Bernard:
Yeah, that sounds really interesting, and it’s really useful to get the context from someone who’s been in that space and understands the sort of the trade offs from a government perspective, because as we all know, there’s obviously many stakeholders involved in this process. So hearing a little bit from that government side of things is very important.

Liam Sides:
Thank you for having me on for that.

Anthony:
Thank you.

Jake Kuyer:
Great. Fascinating stuff. Thank you for having that conversation and being a guest on today’s episode. Anthony. I think we’ll just end with you giving us a quick plug as to where people can actually find the index, or how they can get in touch if they want to discuss anything raised in today’s episode in more detail.

Anthony Bernard:
Yeah. I mean, you know, you can just search for our Global Cities Index online. You can Oxford Economics. It’s one of the sort of key pieces of research we have out at the moment. I’m happy for anybody to email me directly any questions they have. I’d love to continue this conversation. And yeah, thank you for having me on today.

Jake Kuyer:
Thank you and have a good day. Everybody.