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Fri June 14, 2013
The Population Problem
What will the world of tomorrow look like? The frozen, post-apocalyptic wasteland of The Day After Tomorrow, perhaps? According to Michio Kaku, professor of theoretical physics at the City College of New York and author of the recent book The Physics of the Future, not quite. He lays out his predictions and solutions for two major issues facing the world of 2100: growing population and climate change.
- Michio Kaku: professor of theoretical physics at the City College of New York and author of The Physics of the Future.
Population Boom—and Bust
Over the last one hundred years, the world’s population has followed a steady trajectory: up, up, up. In 1950, 2.5 billion people called Earth home; by 1980, that number had reached 4.5 billion. Today, the population has exploded to an astounding 7 billion people.
In the future, however, Kaku predicts that this trajectory will be shaken up. Factors like urbanization, prosperity, the education of women, and the green revolution have the potential to stop the kind of growth we've seen in the past.
“If you’re a poor peasant, you do a calculus. Every child you have makes you richer. Every child means more hands in the field, and that’s your social security when you’re old. But once you urbanize, every child makes you poorer, because you have to pay rent. They go to school. They don’t work in the fields anymore, and you have to house them in a city,” Kaku says.
The result, Kaku argues, is that the graph of the population will begin to look less like an upward climb and more like a straight line. Kaku predicts that by 2050, population will begin to flatten out around 9 billion people, and by 2100 it could stabilize around 11 billion people.
Not Quite a Hollywood Movie
A planet with 11 billion people on it is livable, Kaku says, but will require some lifestyle changes and expectation adjustments. “If everyone wants to live like in a Hollywood movie — Hollywood has brainwashed us into thinking we’re going to have two cars and eat hamburgers all the time — that might be a stretch. We might not have resources for everyone who wants to live like in a Hollywood movie,” he says.
“However, to have a decent life — to have clean water and a nice job and to have a decent life — that may be possible for 11 billion people,” Kaku continues.
Here Comes the Sun
2012 was the hottest year on record in the Lower 48, but Kaku says there is hope for the century ahead. By shifting away from fossil fuels to a hydrogen-based economy, he says, humans will be able to minimize and control the effects of climate change.
Some of these shifts away from fuels might happen sooner rather than later. In ten years, Kaku predicts that solar power will become competitive with oil once scientists solve the “storage problem” of how to efficiently store solar energy for later use. In Europe, scientists are hoping that a hydrogen fusion reactor, which runs on seawater and is currently under construction in the south of France, will become operational by the end of the decade.
“In the next ten, twenty years, we’re going to enter a new era where global warming is not such an urgent question,” Kaku says.
The End of Wall Street?
Switching to a hydrogen economy may slow down the effects of climate change in the future, but in the meantime, the enormous amount of carbon dioxide that will be pumped into the atmosphere over the next ten or twenty years is going to have major consequences for the planet.
“We’re doing a science experiment — a science experiment on the planet Earth with the future of humanity at stake,” Kaku says.
The results of this experiment will likely include drastic changes. Roughly 50% of the world’s population lives in coastal areas, and as sea level rises, many of the cities these people call home — New York, Venice, New Orleans, and Shanghai, to name a few — might begin to disappear. “Large parts of southern Manhattan, including Wall Street, could be underwater,” he says.
The North Pole, Kaku predicts, may disappear altogether. “Children will think that adults are a bunch of liars. They’ll know Santa Claus does not live on the North Pole because there is no North Pole. That could very well be the reality by mid-century,” he says.
So while the world of the future might have a stable population and a handle on global warming, it may not include the Lower East Side — or polar bears, according to Kaku.