There are 17 Sustainable Development Goals. Many argue that it's too many, and indeed, 17 is a pretty unwieldy number for any country or organization to work with. Some argue, as well, that the goals may be internally inconsistent. We need to remember, however, that the SDGs were agreed through political negotiation and are the product of compromise. As the negotiation process neared completion in 2015, some actually called for decreasing the number of goals. But it would have been impossible to agree on what goals to drop as all, of course, have strong proponents. We are left then with 17 goals, each with a number of subgoals or targets. In all, the SDGs are comprised of 169 targets. Having targets, of course, gives no meaning unless we have the possibility to measure progress against them. Therefore, indicators have been identified for each target that can be used to assess their global status. Here, we see the indicators identified for SDG number one. In total, 230 indicators have been identified for monitoring status of progress against the 17 SDGs. These indicators represent the best methodology we have available today. But many need to be further developed, perhaps even changed to something entirely different in order to effectively measure global progress against the SDGs. And for essentially all targets, we're missing data from many parts of the world. Therefore, there needs to be a focus on both metric development and data collection in order to accurately assess global progress against the SDGs. Under SDG 17, there's actually a target aimed at developing new measures for assessing sustainable growth. By 2030, build on existing initiatives to develop measurements of progress on sustainable development that complement gross domestic product and support statistical capacity building in developing countries. The lack of quantitative metrics for measuring the SDGs is actually serving as a kind of catalyst in focusing research to develop metrics that can be applied to assess sustainability. To illustrate this, I've invited two researchers from vastly different disciplines to tell us about the work they have underway and how it can be applied to the SDGs. My first guest is Professor Peter Birch Sorensen from the University of Copenhagen. Peter is a professor in Environmental Economics. Peter there's an SDG that actually focuses on economic growth and and usually, we measure economic growth by using GDP. But what exactly is GDP? Well, GDP stands for gross domestic products. So it's a measure of you can say, economic activity, mainly market activity plus activity in the public sector. How does it relate to sustainability or does it relate to sustainability? Well, not really. There's a clear relation between GDP and the material standard of living. But the problem is that the GDP does not account for the costs to the environment of economic activity. But that's, of course, why in the agenda 2030, it actually states that we need something to supplement GDP. What would happen for example after a hurricane, when you rebuild after a hurricane? Wouldn't that have a tendency to increase GDP? Yeah, for a while, because there would be extra construction activity to repair the buildings and roads and bridges and dams and so on. But we claim that's improvement. That's obviously not an improvement in our welfare. It's just the cost of restoring, getting us back to the point where we came from. That just shows a GDP suits not be taken as an indicator of human welfare. And the economists who invented the concepts never considered to be an indicator of welfare. Human welfare also depends on a lot of other things including the ecosystem services, which are the basis for life. And sometimes, an increase in GDP can take place at the expense of destruction or deterioration of these ecosystems. I know in your research that you're trying to actually work on this question of how can we make other kinds of indicators that support GDP. In finding these new indicators, do we it need an entirely new indicator or can we just supplement GDP? Well, I think it would be very difficult to find one single indicator of human welfare in all its aspects. What I do in my research is I try to adjust GDP or subtract the costs of environmental destruction. If some aspects of the environment have been harmed during the year, I try to estimate the cost of that and subtract it from GDP. On the other hand, if some investment has been made to improve the environment, we should add that to get what I call a green national product. The green GDP, as we call it, is an attempt to at least make sure that we account for, as best we can, the effects of economic activity on the environment. So, we get a better impression of where the GDP growth has happened at the expense of the environment. Is this just an academic exercise then? Or, do you see any kind of rising demand for something like a green GDP in political circles or in societal circles? Well, there are several politicians who have expressed interest in getting such a measure of a green GDP and certainly also a lot of other groups. It's a difficult thing to do, as you can imagine. How do we value the environment? The environment of goods and services are not traded in the market. It's hard to say how much people value them and some people even question whether it makes sense to add up the value of the environment to the value of goods and services produced in the market. There are many controversial issues involved in estimating green GDP. But there is a growing demand for it because there's this growing recognition that ecosystem services and environmental goods are becoming increasingly scarce relative to the goods we produce in the marketplace. Well, there are all these problems with GDP in terms of sustainability, do we need an entirely new economic system to even measure sustainable development? Of course, just measuring the damage to the environment is not enough to ensure that we don't do too much damage to the environment. So we need stronger environmental policies. We need to manage our natural resources and ecosystems much more responsible than we did responsibly than we've done in the past. That means that we should try to put a price on environmental goods and services, say, via pollution taxes so that we as consumers or business firms are confronted with the environmental costs of their actions. If that's impractical, not possible for practical political reasons, we need regulations, environmental regulation that constrains economic activity in areas where it's harmful, too harmful to the environment. So, in that sense, we need to reorient our economic policies. It can still be done in many cases in a way that is compatible with the workings of markets. It's actually a way to get markets to work better. So what you're really saying is that we can actually use the market actively as a tool to help reach sustainable development if we rethink some of the approaches that we've had? In many cases, we can. Yes. My second guest is an engineer, Professor Michael Zwicky Hauschild, from the Technical University of Denmark. Michael's work relates directly to SDG number 12, responsible production and consumption, which is one of the goals which gives a particularly great challenge for many developed countries. One of the SDG that many countries are really struggling with is number 12, which is responsible production and consumption. But how can we really know if something we buy is responsible, if it's sustainable? Are there any methods to actually measure that? I'd like to take a step back and say, well, really, all products are part of consumption. So, really, what we should start with, I think, is the Brundtland Commission for sustainable development about meeting the needs of present generation without compromising the ability of future generations to meet their own needs because that's really what it's about. So, a sustainable consumption is a consumption that we can have without jeopardizing future generations, without undermining, if you like, the material basis of that consumption. And that consumption, of course, is performed through products that we buy. So, if we want to talk about whether a product is sustainable, we need to first talk about whether the consumption pattern is sustainable. And what is sustainable there really depends on a number of things, for how many, how many people are we that has this consumption. So, population numbers in the world and certainly also affluence, levels of affluence, and how it is distributed around the world. And a lot of the other SDGs focus in on that, how everybody in this world can have a healthy life and access to education and so forth. And that entails consumption. So, there are some absolute limits that our consumption needs to stay inside. And if we are nine and a half or 10 billion people as we are are predicted to be around 2050, then, of course, the space for each of us will be proportionately smaller than it is today. If we can agree that everybody has the same space, they're many ethical elements in this and talk about how doe we share it? So, that's really not straightforward. But one approach could be to say, well, we all have the same share of that space. Then, that tells you, that gives you actually a budget of greenhouse gas emissions, how much can your activities cause release of every year? And that gives us two challenges. One of them is to say, okay, I have this space, how much of that should then be assigned to food, to clothing, housing, transportation, whatever it needs activities as you have? That's one thing. And the other thing is, so if I would like to consume this product, what are then the greenhouse gas emissions associated with that product? And when you want to answer a question like that, so you could in principle put a CO2 target or greenhouse gas target on each product, just like you have a declaration of content, you could also have a declaration of environmental impact. So, which climate change impact has this product then caused or does it cause? And in order to determine that, you need to look at the whole life cycle of the product. So it's not enough to just look at your contact with the product. You consume it. You use it to drive your car. Of course, you have CO2 emissions if you drive a petrol driven car, but there is also CO2 emissions or other greenhouse gas emissions involved in the production of the car and in the mining of the ores that give the metals that go into the car. And in the end of life of the car, the treatment there, all of these activities constitute the life cycle. So, from the cradle to the grave, it's also sometimes calls, and this was climate change. But, of course, there are many other environmental impacts than climate change. And if we want to be sustainable, that means, meet the needs of our working generation without compromising the ability of future generations to meet their own needs, we can, of course, not erode the ecosystems in other senses than climate change as well. I mean, there is acidification, there is release of toxic substances, there are also human health impacts through the environment like particulate pollution that we hear a lot about nation cities, and so forth, many different types of impacts. And those as well, you need to quantify and you need to ensure that this product's impact, together with all the other products that you consume, these impacts together stay within the environmental space. We know, at least theoretically, what sustainability is when we talk about production and consumption, but we really don't have the mechanisms yet to be able to label a single product as being sustainable, but it could come that there's lots of research going on. There's a lot of research going on, and there are some, I would say, the challenges that are there are really manageable. And a lot of it is really also political, to decide, for instance, as I said before, how do we want to share this space that is there? So, there's scientific challenge in quantifying this space and then there's a political challenge in deciding how to share it. But I think it's very promising actually to work on different ways of taxing products based on their environmental impact because we can put numbers in the environmental impact. And we could have product taxes follow the impacts so that the products that have a high environmental impact have a higher product tax than the good products. That would be a way of using the market to direct demand in the direction of the more sustainable products. Thank you. I find all of this research aiming at developing new metrics for assessing sustainable development to be incredibly exciting. As our understanding of sustainable development evolves, so does our ability to quantify it. We zoomed in on only two examples of metric development here today, but this kind of work is going on in many disciplines and will be increasingly useful as implementation of the SDG's progresses.