ow 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 i