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Can The Earth Support 7 Billion People?

DotEarth’s Andrew Revkin on what happens as the population explodes: “The old messages of ‘woe is me’ and ‘shame on you’ are so 20th century.”

Journalist and author Andrew Revkin writes the Dot Earth blog for the New York Times, and he’s a senior fellow at the Pace Academy for Applied Environmental Studies at Pace University in New York. EarthSky spoke to him shortly before Earth Day on April 22, 2011. He reminded us that–by the end of 2011–the number of people on Earth is expected to reach 7 billion. That’s nearly twice as many people as there were in 1970, the year of the first Earth Day. Andrew Revkin spoke more about our human population, energy, and Earth Day 2011 with EarthSky’s Jorge Salazar.

What are your thoughts on Earth Day 2011?

It really is the best of times and the worst of times. Despite the recent turbulence, the overarching trajectories for human affairs right now are pretty good. There are fewer children dying prematurely of avoidable disease. There are longer lifespans. There is a reasonable amount of biodiversity still left to lose, which is both good and bad.

But, if you looked at us like bacteria plunked down on this Earth, we’re approaching the edge of the “petri dish.” We’ve been growing at a blazing pace. Now there really are signs of fundamental limits on things, including the capacity of the atmosphere and ecosystems in the oceans to absorb greenhouse gases. There are biological systems that are hurting.

Earth Day was inspired in part by a response to a 1969 oil spill in California. Bring us forward to today, with the Gulf of Mexico oil spill in 2010 and the partial meltdown of the Fukushima nuclear power plant. Has much changed in terms of energy and the environment?

In looking at those particular environmental and energy calamities, a common element was an underplaying of the importance of worst-case risk. That’s something that I’ve written a lot about on Dot Earth. I wrote just the other day about ancient stones, some of them not so ancient, that are along the northeastern coast of Japan. The stones warn about the risk of tsunamis: “don’t build below this stone.” Most of them were completely disregarded in just a couple of generations. The standards for building the nuclear power plants in Japan didn’t even require considering tsunami risk until 2006, even though there was an enormous tsunami on that same coast–though a different part of it–in 1933 and in 1896.

The common thread is not taking seriously the prospect of these really serious and not-hard-to-predict calamities. In fact, they seem almost inevitable, if you look at at them in hindsight.

The questions are, what do we need? How much energy use can we avoid through behavior change, lifestyle change? That is versus how much are we going to need fundamentally as we head toward having two billion or three billion more people all seeking decent lives.

If we were all vegan monks, this wouldn’t be such an issue. But we’re not. There’s very little sign of the burgeoning global middle class wanting to give up the modern conveniences.

What did you mean by saying that we’re not all vegan monks?

Well, we’re not. As people become less poor and become a little more wealthy–moving through middle class lives toward upper income lives–we develop appetites. The amount of meat we eat goes up, and it’s usually working your way up the food chain toward the most energy intense, water intense, land intense sources of food–beef, at the top of the chain, or bluefin tuna at the top of the ocean chain. And that’s unfortunate, because again, you can probably fit a billion reasonably wealthy people on the planet consuming at the top of the food chain. But as everyone moves toward that middle class zone, you really do get a sense that something has to give.

And there are even some resource optimists such as Vaclav Smil at the University of Manitoba–who is one of the Yodas of this field, one of the absolute go-to people–who says that, in the end, he sees even the wealthy having modulated diets away from the habit of eating whatever we can eat, just because we can afford it.

In 1970, the year of the first Earth Day, there were 3.7 billion people on Earth. Now there are nearly 7 billion people. How has people’s thinking about Earth Day changed?

There has been a shift in thinking from the first Earth Day to now. Back then, Paul Ehrlich’s description of the population bomb was perceived as a global threat that would cause mass mortality and suffering. And, in fact, what has played out has been much more like what I wrote about on the Dot Earth blog several years ago. That is, population cluster bombs have been exploding. Little bomblets, here and there. Some not so little.

Population cluster bombs are in areas where you have persistent high fertility rates and deep poverty, such as many parts of sub-Saharan Africa and parts of south Asia. You have high mortality rates–for example, a woman with 15 kids, half of whom will die before they reach their teens. In the same places, you have no real energy choices. The energy poverty, combined with high population locally, can impact ecosystems. People are out scouring for firewood, for example. And firewood is a very inefficient and destructive form of cooking fuel. There are so many options that are cheap and better for you than firewood.

So the difference between 1970 and now is that the population problems around the world are a hugely uneven map. You have exploders, as Jesse Ausubel at Rockerfeller University describes it. And you have imploders, where population is declining steeply, like Russia. And Japan, by the way, is probably going to have half as many people as it has now, later in the century. So the world is very imbalanced. And that kind of situation, with local pressures, creates another thrust, which is more pressure to immigrate or move. That’s another whole issue.

In addition to migration across national boundaries, the majority of people on Earth today live in cities versus rural settings, the countryside. Your thoughts?

Cities are hugely important. They will make or break this century, in many ways. In other words, if you have functioning cities that are resilient–that can provide basic living standards for people who come there looking for work–they can probably take an enormous amount of pressure off ecosystems and foster much quicker advancement for people. There are a lot of studies around the world showing that, when you move to a city, access to education increases, access to income increases, your energy footprint goes down.

It depends on the city, though. Some cities–as a recent study by the National Center for Atmospheric Research found–aren’t the dream city, the environmentally efficient city. That study suggests that cities make choices that matter a huge amount to how this century can work out.

Projections by experts at the International Energy Agency (IEA) suggest that the growth in energy use to 2030 will happen in the emerging economies, like China and India, while the wealthier nations’ use is more or less flat.

Looking at energy, and in particular climate, the IEA said that 98% of the growth in greenhouse gas emissions is coming in developing countries in the next 30 years. So that means mostly China and India. And that’s a big deal, because the trend here in the U.S. is toward flatter, or slightly declining emissions for a long time, even without new policies.

The action is all still elsewhere. So even if the U.S. had a perfect policy–the most aggressive climate standard, where we turned off every engine and stopped driving and all started telecommuting and somehow afforded solar panels and geothermal–the climate system would barely notice, because all the action is elsewhere.

So that says, to have a realistic approach toward limiting climate risk in the coming decades, if you’re not looking at energy issues in China and India, you’re really missing the boat.

There’s another side to this, which is that there is population growth here in the U.S., too. While many industrialized countries are shrinking, like Japan, the United States is an outlier. We’re going to go towards 400 million or more Americans in just a couple or more generations, from 300 million or so now, mostly through immigration. When someone either moves here or is born here, they have a much higher energy footprint than someone born in Haiti or Bangladesh.

As we approach 9 billion people by 2050, what’s something you want people to think about?

The key to me, in looking at these issues for a very long time, is that a new way of thinking is required. The old messages of “woe is me” and “shame on you” are so 20th century. They’re not a good fit for the issues we face now.

If you look at an issue like energy–and you’re always pointing at someone like Exxon or a politician–you’re missing the reality that we all need energy. For instance, I have an oil-heated house, not because I would like that, but because there aren’t options. And so if we want to really get busy and move off of the fossil fuels of previous centuries and go to something new and sustainable and renewable, then we have to take on that responsibility and get busy.

And I see that as a very positive prospect. We are so disinvested in things like basic research and development in energy that it would be really simple and easy and cheap to greatly increase it. A two-cent nudge in the gas tax–yes, I mentioned the word tax– would triple our R&D for energy. If you could guarantee that money would go to that, I think a lot of people would actually like that idea.

I have a very optimistic sense of, at least, a chance of a fairly smooth ride past this mid-century peak that we’re facing. And the question that we have to examine, which I wrote about on Dot Earth not long ago, is which comes first, peak everything or peak us? In other words, can we manage our way through a soft landing, a soft transition to a new relationship with the planet? Or are we going to have that change in our trajectory imposed upon us by limits? That’s a function of how busy we want to be.

What’s the most important thing you want people today to know about Earth Day in a year of 7 billion people?

That there’s every chance the next 30-year period will be one of great innovation and collaboration around the world. It just takes a little bit of focus to get you engaged in the conversations and the actions that are needed for brighter outcome.

Listen to the interview here:

Written by Earthsky.org

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