• Some highlights from this interview
• Developed countries must act first
• His brief conversation with President Bush
• The huge challenges in India and China
• What can individuals do?
• The Great Depression's lessons

In brief, what is the IPCC process?

The IPCC ... is an intergovernmental body, so all the decisions are taken by consensus by all the governments of the world. That in itself is a major achievement.

We carry out assessments [by mobilizing] the best experts that we can get from all over the world. We start by writing to some governments and some organizations that could provide the expertise or at least point us to where the expertise is.

We get nominations with the CVs of all the experts who are nominated, and then we carry out a process of selection. This, incidentally, is ratified by the bureau of the IPCC. And the bureau is elected, generally, with geographical balance from all over the world. Then we start working on the assessment. Of course, the outline and the contents are determined by the governments because, essentially, we carry out policy-relevant assessments. And therefore, it's the policy-makers who have to tell us what would be relevant to them.

How many authors of the final report were there?

If you look at the Fourth Assessment Report, there are roughly 600 authors. But if you count the number of people who have been involved in the review process, as well as those who have provided inputs in what we call contributing authors -- these are people who may have specialized expertise on, let's say, hurricanes or ocean science -- ... there are several thousands of people who really get involved in the IPCC. ...

There is a lot of talk about how the IPCC consistently has been revising its projections toward a more dire outlook. Why is this? Have you been too conservative?

We really have to go by available knowledge. ... Now, what's happened over a period of time is that our knowledge has certainly increased by leaps and bounds.

And there were several gaps. There were several deficiencies in earlier research because people were really new at the game. And those have now been filled up. So now we have a much more accurate picture of what's going to happen.

Should we expect things to continue to move in that same direction, more and more dire forecasts?

Not necessarily. I think what's also happened is that climate change has accelerated in recent years, and now we have much better observations on the basis of which we can see the direction in which we are going. So it's really coincidental that our knowledge has only revealed that things are probably going to be much worse than what we had expected earlier.

You say that with a smile.

One has to be dispassionate about these things.

Why do you say, "One has to be dispassionate"? Don't we all need to be shaken?

Yes. But I think those who are carrying out the assessment shouldn't allow emotion to enter into whatever we do. I think we have to be, in a sense, coldly objective about the information, the data and the research that we are evaluating.

There are some voices out there saying that you're alarmist; that, in fact, this isn't a crisis. Is it a crisis?

I think if the information and the assessment appears to be alarming, then it's for people to decide what kind of response they would have, whether they'd be alarmed or just take it in stride. ...

I wouldn't say we're facing a crisis. We're certainly facing a very difficult challenge. Of that there's no doubt. And I think the sooner we realize that, the better. And if we don't meet that challenge, then certainly it could lead to crisis. ...

I'm going up into Everest Base Camp in a few days, and we're going to take some pictures of the glaciers there and compare them to pictures that were taken in the '20s. What is the importance of those glaciers to India and China?

Oh, it's huge. We have assessed that over a period of time, about 500 million people on the subcontinent ... and 250 million people in China ... are going to suffer from water scarcity as a result of the melting of those glaciers. Most of the river systems in the northern part of the subcontinent are essentially originating in the glaciers. And with the rapid melting that's taking place, initially you will have flooding. You will have excess water flowing through them.

And after a couple of decades, when the mass of these glaciers shrinks, you would have an inevitable decline. The consequence of that is not merely that people use [water] from the river systems themselves, but [that] these rivers serve an extremely important purpose in terms of recharging groundwater throughout a large expanse. It's bad news for a large number of people.

How do you adapt to that?

You just have to manage every drop of water more efficiently. You see in India, for instance, over 80 percent of the water goes into agriculture, and much of it is wasted. We have to use drip irrigation. We would provide incentives, disincentives, better education for the farmers, by which they move to much more efficient water management systems.

How fast are those glaciers melting?

I think we'll be in trouble in the next two to three decades. And we have a picture in the IPCC which shows the record of decline of these glaciers. It's there in the Working Group I report.

Your prime minister calls it the "water tower for India."

Well, he's absolutely right.

We hear a lot about Greenland and the Arctic and Antarctica and relatively less about what some people call the "third pole," the Himalayas.

In terms of the extent to which it will contribute to sea-level rise, it is much lower than you would get, let's say, from the collapse of the Greenland ice sheet. ... In terms of the impact on the lives and livelihoods of people, this is a far more serious problem. ...

Adaptation, in that case, may save many lives. But it's hard to imagine how one can adapt to a collapsing system that supports seven rivers going through India and China.

It's very, very difficult. I think we'll really have to use every drop of water efficiently. It means a totally different system under which we function. But that will also lead to a lot of migration of people. After all, if one looks at the history of India, people settled around the river systems. When the Aryans first came from Central Asia, it was the river systems, the greenery all around them, which attracted them. And we're turning thousands of years of human history around and perhaps leaving people with no choice now. ...

You've called for action first from the developed countries. Why?

[There are] two reasons for it. Firstly, if one looks at the historical responsibility for the problem, the fact is that the concentration of greenhouse gases is essentially the result of emissions that have taken place for 150-plus years, largely in the developed countries.

The second reason is that, in terms of economic and technological capacity, the developed countries are certainly better equipped to do something about this than the developing world.

And finally, I think the developing world still has a large number of poor people who have no access to modern forms of energy, and you can't possibly deny them that access. Therefore, you need to create capacity and produce energy to fill their needs.

You say that over the last 150 years, most of the carbon has come from the developed nations?

Right.

But today the largest emitter of greenhouse gases is China.

I agree. But would you take a geographical entity as being the criterion for responsibility? If you look at per capita emissions, China is still way below several parts of the developed world.

True. The climate, though, doesn't really care whether or not it's a per capita figure or a gross figure; it's going to be affected. If China and India continue along the path of growth that they're on, there's nothing the West would be able to do to prevent catastrophe.

I think what is required -- and I think this was clearly enshrined in the [U.N.] Framework Convention [on Climate Change] -- is that the developed world has to reduce its emissions, and, as is becoming clearer, they would probably have to reduce [them] quite substantially.

By 75, 80 percent, I understand?

It depends on where one wants to stabilize the concentration of greenhouse gases and, therefore, the equilibrium temperature increase. And that's something that the negotiating body under the Framework Convention has to decide on. But it was clearly intended that the developing countries will have to increase their emissions. Now, I'm not saying that they have to increase it along exactly the same path as the developed world has followed, but I find it a little difficult to understand why a geographical entity should be the definition of responsibility.

For instance, let's assume, theoretically, that China broke up into 20 different countries. Each state became a separate nation. Who would you hold responsible? They would be very much smaller entities, but they would still have much lower per capita emissions than the developed world.

On the other hand, there are some countries that are really very small, but they're huge energy guzzlers. And I don't want to name them. I think there has to be some degree of parity. ...

When we talk about the developed nations, we've then set the standard as nations. We're then talking about nations. And so that leads people to say, "Well, [wait] a minute," ... and then they point fingers at India, ... which will, not long from now, be the most populous nation on the planet, ... and [at] China, of course.

Yes, of course. When governments have to come to some agreement on what to do, they represent the geographical entities that define those countries; I agree. But I think it's also essential to look at what every human being that is part of a particular nation is confronted with.

If there is a huge amount of scarcity as far as energy use and access to energy is concerned, I think that's a reality that people have to take into account.

But in the United States, the president himself has said in the past that there's nothing that we can do if China and India don't slow down their growth.

Sure. But I think what really should be the focus of action and attention in the developed world is to clearly demonstrate to the rest of the world that there is a desire and enough action to cut down in emissions in the developed world. That, in my view, has not really happened. It's unfortunate.

The Framework, I mentioned, on Climate Change came literally into existence in 1992. We are 15 years down the road. But even under the Kyoto Protocol, there are some countries that are not likely to meet their commitments.

Have you been able to talk to the president of the United States about [climate change]?

Briefly, for about a minute.

Can you describe the conversation you had with him?

This would sound a bit mischievous. I met him in New Delhi when he was visiting India. My prime minister introduced me to him at a lunch. I said, "Mr. President, I'm the person responsible for that organization which brings out those horrible reports on climate change." And I said it with a smile. And he said: "Yes, I agree. But we need to find solutions, and I think nuclear is a solution. Do you agree with that?" I said, "I certainly don't disagree with that." And he says, "I think technology is a solution." I said, "Yes, but technology has to be disseminated on a large scale." That's the extent of the conversation that I had with him. ...

It's pretty remarkable that your body, the IPCC, which you head, and the president of the United States have not had more than one minute of conversation.

Well, yes. As a matter of fact, I spoke to some friends in the State Department. I said, "I need five minutes with him." And I was told, "Look, you think he has five minutes even for someone who's an official in the State Department?" ...

Have you written off the president of the United States, [or] are we just waiting for the next administration to come into office? ...

I really have no business commenting on any country's policies. But if I'm asked to, I will say things are moving in the U.S. I'm not at all pessimistic. It's a democracy where, if the people want something, if the states and their leadership want something, the federal government will respond. And I think you can see that response already. ...

Let's talk a little bit about big business and climate change in the world. What do you think can be expected of big business? Big business looks at markets, opportunities, profits. Can you really expect big business as an ally in fighting climate change? ...

If climate change is going to have an impact on economic activities all over the world to varying degrees, business has to take that into account in devising their own plans.

We should also accept the fact that the world in the future is going to be a much lower-carbon world. And if that's the case, those companies that adopt and come up with technologies and methods of production that are lower in carbon intensity are really going to be the winners. And you see some signs of that in some companies already. I can mention a few: GE, DuPont. These are organizations that have read the writing on the wall and are making investments, making moves to develop low-carbon technologies and renewable energy technologies.

Right. But we depend heavily on coal. In India, 55 percent or more of the electricity comes from coal. In the United States, it's 52 percent, I think. China, a large percentage of it is coal. There's no technology available now, and [we are] not [going to even have an idea whether clean coal technology can work] for some 12, 15, 20 years.

One of the things that we've brought out very clearly in the IPCC working report is the need for a price on carbon. A price on carbon would have to be somewhat across the board. And it may have some built-in delays for a few societies. But if that signal was to come out clearly, you'll see technologies being developed pretty rapidly.

I think the capabilities are there. It's just a question of putting in the resources. ... Even the burning of coal can be made far more efficient. You could capture the CO2 and sequester it. You could come up with more efficient boilers, more efficient technologies.

I think it's well within the reach of human society to devise these solutions. But there has to be a market force. There has to be a market signal on the basis of which all this happens. We haven't done that. And I hope that's something that will happen in the post-2012 period.

When you look at India and China, you see a gold rush taking place. Foreign capital is pouring in, all to take advantage of the tremendous growth in those markets. Capital is not coming in to build clean technology. The message that I'm getting out of that is that there is no conscience about climate change in the activities of those businesses.

I'm very concerned. I think it's for governments, both in China and India and other emerging economies, to set in place policies that would ensure that we don't make the same mistakes as the developed world. I see some signs of that changing. I see a clear indication [of] that at least at the highest levels of the government, both China and India. I'm pretty familiar with both countries because I've associated with policy advice bodies in both countries. ...

But both of these countries are sporting a new billionaire class. Some of the richest people in the world now are Indian industrialists. Honestly, do you see them acting to prevent emissions or to grow the economy as fast as they can?

I don't see them giving the right kind of attention to these issues, and I feel deeply concerned about [this]. This is where civil society has to get very active. The media has to get very active. ... Mahatma Gandhi said that the owners of capital are not really owners of capital: They're trustees on behalf of the public.

If we completely throw that principle and that belief out of the window, it would be tragic. I think our leaders of business and industry have to be much more sensitive to the needs of the poor, the need to protect the environment, than you see any indication of at this point of time.

Mahatma Gandhi's concept that they're trustees for the public is a quaint concept in today's world. Most corporations see clearly that their obligation is to Wall Street or the big markets or to the shareholder.

I agree. But if Wall Street also starts incorporating some of these concerns and if, let's say, a company is scrutinized by the public in terms of not only what it produces by real profits, but also what it does in terms of its responsibility to society, it would certainly affect their business.

We're living in a world where reputation and public opinion are extremely important, and I'd like to see much greater force in these factors determining the actions of a company. And I feel very concerned that in a country like India, and China as well, it's not happening to the degree, not even to half the degree that it's required. ...

We visited an SUV plant and talked to Anand Mahindra. He wants to be one of the top three SUV manufacturers in the world. Why does the world need another SUV?

Well, if he manufactures an SUV that is very efficient, that uses biofuels or fuels that have no environmental impact, I would certainly support him. But if he's going to base his business on only SUVs, then as soon as I get back to New Delhi, I'm going to telephone him. He's a good friend, and I'll tell him: "For heaven's sake, spend a little more on public transport. Try and innovate some means by which we can provide better public transport for the people."

You're going to call him based on this conversation?

If you want me to, I would. I'd like to.

He says that his SUV gets 20 miles to the gallon. I asked him, "Why not have a car that gets 30, 40, 50 miles a gallon?"

I would go beyond that. I would say, "Devise some public transport systems where you can carry maybe 50 or 60 people in one vehicle, and come up with very efficient energy consumption per passenger kilometer-hour."

How powerful is the auto and highway lobby in India?

It's getting frighteningly more powerful, if I may say so. ...

Can I quote you? You said in May: "The automobile industry and highway lobby is so powerful, it will block any kind of development of public transport. We are blindly aping the West."

Yes. I wouldn't want to eat my words at all. I am concerned about this. It's something to worry about. We're not doing enough to modernize our railway system, which really has enormous potential. The kind of kilometers of rail lines that we have in the country is a major asset, and we should build on that. We're not doing enough at all. And I've said this to the highest levels of the government. ...

Environmentalists have tried for a long time to improve public transportation and haven't been successful.

I agree. But there's a certain time, as they say, in the affairs of men when we have to catch the bull by the horns and make sure that we use the opportunity to turn things around. It appears to me that, in terms of public awareness and concern on some of these issues, we are probably at a tipping point. And I think if we start moving in the right direction, perhaps there will be a lot of public support. Maybe this wasn't the case earlier on. ...

But there are very few companies that take strong leadership positions.

That's where I think you need strong government policy. I think you really need to accept the fact that people are not going to bring down their profits just to be able to please the public. I think the public has to put enough pressure on companies. I think the legal and policy regime has to be such that companies will move in the right direction.

In the absence of that, yes, people may do a few things here and there. But they're obviously not going to jeopardize the interest of the shareholders. So somehow what we need to do is to ensure that there's common ground between the interests of the shareholders and that of society. And this is where enlightened government legislation, regulation, incentives, disincentives, can make all the difference.

We started talking about ... signs that big business was going to really contribute to this. But what you're finally saying is that it's going to take government to really push them?

Yes, as well as civil society. I think reputational risk is something that companies are not going to court voluntarily. If they feel that their reputation is at risk, if they follow one path or the other, they would certainly change the direction. And I think that's where civil society also has an extremely important role.

I welcome any tougher words from you, if you wish, on this subject of business. ... It seems important that people understand that businesses are not going to just jump on this for the sake of the public.

You've got to be pragmatic about these things. There's no sense in living in a world of make-believe. These guys are there for a very specific purpose, and they'll find every possible way of meeting that purpose. So you've got to make it absolutely essential for them, or you're going to leave them with very few choices if you want to move them in a particular direction.

So you have to herd them? You have to change the rules of the game?

You have to. And those rules of the game being changed can come from government. But it can also come from society. It could come from consumer organizations. It can come from civil society NGOs [non-governmental organizations] and the media. It can make an enormous difference, though I must say I find increasingly that, off the record, these guys buy up the media in our country. They have such enormous influence over some of the leading newspapers and, I would say, even increasingly over the TV channels, which used to be very objective and very fair in the past. Big money is a big danger. And with the growth that's taking place in India, these big boys are acquiring a lot more muscle.

And in China, I'm not sure from what you say if there's an advantage to having a politburo that dictates what's going to happen in a country, or if it's an advantage to be a democracy.

Well, I would say any democracy is 10 times better than what you have in China.

So the world's most populous nation today, China, doesn't have a civil society, doesn't have a judiciary.

That's why you have disasters like the Three Gorges Dam. We just displaced God knows how many millions of people, sunk in so much money, and already that facility is declining in performance and creating all kinds of environmental nightmares around it. But they got away with it. ...

I've been going to China since 1981 and have a good relationship with Tsinghua University. We worked with them over the years. In the '80s, these guys would talk about the Three Gorges Dam and say there are too many environmental problems.

That was the official party line. And now they've all turned around and said, "It's a very good dam," because they dare not say anything against it. There is no civil society or dissent.

So we're up against huge market forces. We're up against powerful governments. Just what are we going to do to meet the challenge?

Maybe I'm placing undue emphasis on knowledge, but I think knowledge and awareness can make an enormous difference. There have been monoliths. There have been powerful forces like the former Soviet Union that really couldn't withstand the power of the people. And now something like that may be necessary in this area as well.

Through public pressure, through activism by civil society and government laws, which of course will all be a function of these pressures, we might be able to change the rules of the game.

The Soviet Union essentially collapsed because it was unworkable, because the system couldn't support itself. If we apply the same model here, perhaps, the cost is too great. If we just wait for the planet to choke on its own emissions, it will be too late. We have an enormous challenge here of trying to get people to pay attention to something well before the time of crisis. You say we're facing a challenge, not a crisis.

I would have believed in this view maybe a year ago. But I think the last six months to eight months, I see a perceptible change and a shift. I think people are today deeply concerned and fully aware about where we are heading. And that gives me some basis for hope that maybe things will happen before we run into any crises.

Now, whether this is a permanent state of affairs or permanent expression of deep concern that you see all around us, I'm not sure. But my feeling is this time it's for real. People are really, really worried. ...

People understand there's a problem, and they want answers. They want to know how we're going to get electricity cleanly, how we're going to drive cars, how we're going to fly airplanes and how we're going to make things, manufacture things without polluting more than we do. But it's unclear what those answers are. What do you say to that?

That's where I think you need a lot of intellectual effort. This would involve all the stakeholders, business, industry, government, civil society, to be able to come up with some of these answers. You really need a major, vigorous debate on this subject to be able to articulate the solutions that are required. I'm afraid we're not doing that at this point of time. ...

Does it frustrate you that this is getting beyond the purview of what the IPCC can do? The IPCC is about knowledge, about science, about informing the world about where it's headed and what the consequences are going to be.

The IPCC does not do any policy-prescriptive work. We only do policy-relevant research. And I think to that extent, if we've highlighted the fact that if you want mitigation at a certain level, it's linked to a price of carbon, of X, Y or whatever, I think we've done our job if we can convey this message powerfully. Then it's for societies, it's for government to decide at what level they will pitch the price of carbon.

But we've clearly articulated this message that there has to be a price on carbon if you want mitigation.

Does the IPCC go home after delivering its message?

As far as I'm concerned, I place very heavy emphasis on outreach of our findings. I've always believed -- and I've said so, and I've acted accordingly -- that it's not enough to produce good reports. You've got to get the message out. And I think today, those who are involved in scientific activities must be good communicators.

And I see the next few months after the release of our synthesis report next month as an important period when I, and of course, other colleagues in the IPCC spread the message.

You raised the issue of these scientists having to be good communicators. But very few scientists are good communicators in a popular sense. They're so qualified in what they say and so careful that it's often misinterpreted.

I agree. But that's where I think we need to work with partners. We don't necessarily have to speak out the messages ourselves. We provide the inputs to partner organizations who are good at that. But this would require an active effort on our part, because if we just sit back and say, "Oh, it will happen," it's not going to happen. We have to make that effort to reach out to those who can become our allies in spreading the message. ...

What should individuals do? Whether in China, India or the United States, Indonesia, Europe, what should they do?

One of the things that we've highlighted in our report this time is the immense importance of lifestyle changes and consumption patterns. I think we have to create a consciousness starting at the level of schoolchildren of how our actions are really impacting on the planet. And I think if we function within that consideration, then perhaps everything we do will take on a relevance that serves the interests of stabilizing the climate.

I think oil companies have predicted that the amount of consumption is expected to double in the next several decades. Electricity consumption is going up rapidly in the United States.

I think these things have to change, and they will change. And I think it's a question of how people accept the extent and the reality of the impending problem. I lived in the U.S.; I was doing my doctoral work when the first oil-price shock took place. ... I remember it distinctly. I used to get up at 5:00 in the morning, go and wait in line, a huge line of cars, to get $3 or $5 worth of gasoline. People took it without a murmur. ... [The] addiction [to oil] seemed to have vanished immediately.

I don't believe that human nature is not capable of making some major changes, but there has to be a rationale. There has to be a basis and a driving force that takes us in the right direction.

And it has to be fair?

It has to be fair and equitable. It must.

India's priority, China's priority, has to be pulling itself out of poverty.

Absolutely. But we have to do it in a distinctly different way from what, let's say, has been achieved in the developed countries.

That seems fundamentally unfair, I mean, that the United States and Europe can come along and sort of pull all this wealth together, and now you're saying that your country and China cannot go that same path. But that's the aspiration of most people in those countries.

I agree. But we have to do it in a different way. To give you an example: Why should we, in villages that are miles away from the electricity grid, have to depend on electricity which is generated through [the] burning of coal? They're poor people. All they need is one single point of light.

Your government is in debt. The capital that's coming into your country comes from big businesses. Those big businesses like centralized power stations; they like grids. They don't profit by distributed power systems, by community solutions. They profit by putting electricity on a grid and sending it out to the village.

I see a lack of imagination in that approach. I think if you have, let's say, a company that's got an excellent distributor system for selling soap or tea or whatever in every remote village in the country, if they get into the franchising -- and I must say the government is now planning to promote that -- of power generation and distribution in every village, it will be a viable proposition.

And what the government is trying to do is now provide a large quantity of the capital that's required as a grant. But the responsibility for supplying power and electricity or whatever form of energy will then be on the franchisee. And that could be a private-sector entity; it could be the local government; it could be a cooperative. I think we have to come up with innovative solutions.

What do you think is the biggest hurdle that you face?

Ignorance and inertia. I think these are the two biggest hurdles that one faces. People are living in a state of blissful ignorance. They don't know how technologies, opportunities, and I would say even the problems that are facing us are changing rapidly. And I think it's absolutely essential for people to be fully informed of the changing world that we're living in.

And inertia, which is also in some sense a function of vested interests -- everybody is benefiting from continuing with the existing system. A shift will produce some winners and some losers. And therefore, the potential losers are going to do everything to block change.

And some of those losers have really deep pockets?

They have deep pockets. They have a lot of influence, and they know how to influence the system. That's why I believe that what you need is to inform the public. People are basically rational. Once they see through the game and they realize that whatever is being suggested and pursued is against their basic interests, I think there's some hope for change. ...

You're an adviser to Prime Minister [Manmohan] Singh?

I'm part of his advisory council on climate change, yes.

So what is India prepared to do?

I think you'll see a lot of action in India. Right now, what's happening is that we've prepared a detailed document on what India should do in response to climate change. This is going to be considered by the advisory council on the basis of which, I hope, clear policy will be declared.

Is India ready to sign a global treaty that puts a price on carbon?

I suppose it would, provided other countries also sign on, because, you know, the big problem about a price on carbon is nobody wants to see any free riders. If there are countries that don't put a price on carbon, then, in the short term, they have a price advantage in terms of production of goods and services.

That's how India and China are perceived, as free riders.

Well, I think historically, that wouldn't be a correct statement, because historically, they're not responsible for having caused the problem to start with. In fact, if anything, they're the victims.

Yeah, I understand that; I accept that. But it doesn't really matter at this point what happened in the past, does it?

It does, because the problem has been caused by something in the past.

Right. But where the problem is going to emanate from now is from the immense growth that's happening in India and China, regardless of what's happened in the West. ... It could be criminal, what's happened in the West. But going forward, what's happening is enormous growth out of India and China. Actually, much of that growth depends on the markets in the U.S. continuing to consume. ... It's a vicious circle, isn't it?

Well, that's largely the case of the Chinese economy, because they are feeding the consumer market in the U.S. on a large extent. That's not entirely true of India.

Right. You were separate from the Western economies for quite a long time.

Absolutely.

But why would the Chinese want the United States to grow more slowly or to consume less when their growth is --

Sure, absolutely. I think we're all part of a global economy, and it doesn't help to have any part of the globe suffering from a decline in economic activity. And that's precisely why I think you need some kind of an agreed, uniform system for pricing carbon, so that nobody becomes a free rider.

And I'm sure if that was to happen, some countries will get an unfair advantage. And that has to be prevented. It wouldn't be correct.

It all comes down to sustainability, doesn't it? It all comes down to the number of people that the planet can support. Does the IPCC have a handle on just what is a sustainable world population?

There are two components to sustainable consumption: One is population, and the other is per capita consumption. And I think you have to look at both. And I might quote Sen. Tim Wirth [D-Colo.]. He came to a conference that we had organized in Washington several years ago. He said: "The U.S. has a serious population problem, ... because we add 3 million people to our population each year, and each person consumes 40 times what a Bangladeshi consumes. So if Bangladesh is adding maybe what, 5 or 6 million a year, we are adding 120 million." So I think you really need to look at both. ...

Let's say that you come up with a figure for average consumption given certain populations. In other words, for this population, we can only consume this. If we go to a bigger size, if we go over 10 billion people, we're going to all have to consume less.

I think that's a fair enough approach, so that governments and people come up with policies whereby they don't increase the footprint of their activities on planet Earth.

This is sort of a macromanagement of world populations that people don't want to hear. But we face extinctions through overpopulation or a catastrophe that kills millions of people at a spell, or we come to grips with this. Isn't that what we're facing?

It's just as much in the interests of countries and societies for local reasons as it would be for global reasons. How can you minimize poverty when the poorest sections of the population proliferate their numbers at an alarming rate? You can't provide infrastructure. You can't provide services. They live in slums. You can't provide jobs.

So I think it's sound policy for domestic reasons just as much as it might be for global reasons.

I'll throw out the Americans. Let's say we all consume about what an average European consumes. How many people can the planet support?

We're in serious trouble. I think even with the present population, we would just create enormous problems. That's why I personally believe that the emerging economies have to find a different path. We really can't end up consuming what is being consumed in the developed countries today. But at the same time, the developed countries also have to start changing direction. They can't continue to consume at this level. And that's precisely why we've highlighted as an important mitigation strategy changes in lifestyle and consumption patterns.

A lot of Americans think that the European lifestyle is pretty ascetic, and they're not willing to step down to that level of consumption. But you're saying even at the level of European consumption, we've overpopulated the planet.

Quite right. I think people in the U.S. have very short memories. If you go back in time to the period of the Depression, that was a pretty miserable period. What were consumption levels at that point of time? It's not as though it was a catastrophe. Yes, it was a very difficult period. But there were also a number of positive features that came out of human behavior at that point of time -- people helping each other, a much greater community feeling.

Wait a minute. Are you saying we need to go back to the levels of consumption of the Depression?

No. All I'm saying is that human nature is quite adaptable. [What] North Americans may see as a distinctly lower lifestyle in Europe may have several dimensions that --

That's what Americans are afraid of. They're looking out here, and they're saying: "This Indian guy, he's head of the IPCC; he's going to cut our allowance. And he thinks we can just handle it. He thinks we can take it."

No. I personally think technology and the ability to innovate today is such that you don't have to give up the so-called good things in life. Take the example of transport. Yes, Americans are living in suburbs; they travel long distances. But if you had a better public transport system --

I go to Washington, D.C., very often. Before the Metro came up over there, everybody thought that this was an enormous waste. Look at the difference it's made to the life of people living in the D.C. area. Why is it that we can't get a rapid train between New York and Washington?

If that was the case, people wouldn't fly between New York and Washington. It's so much easier to go from city center to city center.

There are powerful lobbies that keep these things from happening.

That's the point.

In New York City, the gateway of the United States to the rest of the world, you can't get a reasonable train journey into Manhattan from the airport because of the taxi lobby.

Absolutely.

You can't get public transportation systems in most cities because the car manufacturers have built cities under different rules. We're back to business.

When I go to Houston, Texas, unless you have a car, you just can't get around. There's no such thing as public transport. ...

So there's got to be pain. I don't disagree with that. But --

The only reason why I was going back to the period of the Depression is that was a period of pain. But I think out of that experience, a lot of good things did come. And I think human beings are quite capable of going through a period like that and finding the positives, and then building on them appropriately. I'm sure if people had not been through the Depression, you possibly wouldn't have had the kind of growth, the enormous desire to succeed with economic activities that you found subsequently.

So maybe what the world needs is a good depression.

A bit of a shock. Maybe.

What will that shock look like?

The shock would essentially mean the pain of transition. And there's no getting away from the fact that if we were to bring about a transition, there will be some losers, and those losers are obviously going to depress the economy.

Those losers are going to be those people that are consuming more than their fair share.

Right. And those who are producing goods and services that are essentially polluting in nature as far as a global environment is concerned, they'll have to produce other things.

It's one thing for a politburo to inflict restraints. But how is a politician going to ever survive inflicting pain or shock, as you say, to his or her people?

He would be quite willing to do that at some cost if the people want him to do it. Germany has made a fairly significant transition to renewable forms of energy. But it really hasn't resulted in any great loss, except to a few sections of society.

Shutting down the power plants that were using brown coal and so on, this must have affected local populations and jobs over there. But if you look at the aggregate, I don't think this country has suffered at all by bringing about even the sort of modest transition that it's been able to achieve. So I think if you bring about change, there will certainly be some people who are going to be affected adversely by change.

But this is really the collective will of the people. And you can build a safety net for those who are going to be affected, essentially, through payments from the government from those who are going to gain from the new regime. As you said earlier, unless there is some pain, you're not going to bring about change. It's essential.