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If humans disappeared, what would Earth look like a year later? – Essie, 11, Michigan
Have you ever wondered what the world would be like if everyone suddenly disappeared?
What would happen to all our stuff? What would happen to our homes, our schools, our neighborhoods, our cities? Who was going to feed the dog? Who would cut the grass? Although it’s a common theme in movies, TV shows, and books, the end of humanity is still a strange thing to think about.
But as an associate professor of urban design — meaning someone who helps cities plan what their communities will look like — sometimes it’s my job to think of perspectives like this.
so much silence
If humans disappeared from the world and you could come back to Earth to see what happened a year later, the first thing you would notice wouldn’t be with your eyes.
It would be with your ears.
The world would be calm. And you would realize the noise that people make. Our buildings are noisy. Our cars are noisy. Our sky is noisy. All that noise would stop.
You will notice the weather. After a year without anyone, the sky would be bluer, the air clearer. Wind and rain would clean the surface of the Earth; all the smog and dust produced by humans would disappear.
home Sweet Home
Imagine that first year, when your home would not be disturbed by anyone.
Go home – and hope you’re not thirsty, because there would be no water in your taps. Water systems require constant pumping. If there is no one in the public network to manage the machines that pump water, then there is no water.
But the water that was in the pipes when everyone disappeared would still be there when the first winter came – so at the first cold snap, the freezing air would freeze the water in the pipes and cause them to burst.
There would be no electricity. Power plants would stop working because no one would monitor them and maintain the fuel supply. So your home would be dark with no lights, televisions, phones, or computers.
Your house would be dusty. In fact, there is dust in the air all the time, but we don’t notice it because our air conditioning systems and radiators are blowing air. And as you move through the rooms of your home, you also keep the dust moving. But once all that stopped, the air inside your home would be calm and dust would settle everywhere.
The grass in your garden would grow – and grow and grow until it got so long and soft that it stopped growing. New weeds would appear, and they would be everywhere.
Many plants you have never seen before would take root in your garden. Each time a tree drops a seed, a small tree can grow. No one would be there to rip it up or shoot it down.
You will notice a lot more buzzing bugs. Remember that people tend to do whatever they can to get rid of insects. They spray the air and the ground with insect repellent. They remove insect habitat. They put mosquito nets on the windows. And if that doesn’t work, they crush them.
Without people doing all of these things, the bugs would come back. They would once again have free reign of the world.
In the street where you live
In your neighborhood creatures would walk around, looking and wondering.
First the little ones: mice, marmots, raccoons, skunks, foxes and beavers. The latter might surprise you, but North America was once rich in beavers.
Larger animals would come later – deer, coyotes, and occasionally bears. Not the first year, maybe, but eventually.
Without electric lighting, the rhythm of the natural world would return. The only light would come from the Sun, the Moon and the stars. Nocturnal creatures would feel good to have their dark skies back.
Fires happened frequently. Lightning can strike a tree or field and set brush on fire, or strike homes and buildings. Without anyone to put them out, these fires would continue until they died out.
around your city
After just one year, the concrete – roads, highways, bridges and buildings – would look much the same.
Come back, say, a decade later, and cracks would have appeared, with little plants wriggling through them. This happens because the Earth is constantly in motion. With that movement comes pressure, and with that pressure comes cracks. Eventually the roads would crack so much they would look like broken glass, and even trees would grow through them.
Bridges with metal legs would slowly rust. The beams and bolts that hold the bridges would also rust. But the great concrete bridges and interstate highways, also made of concrete, will last for centuries.
The dams and levees that people have built on the world’s rivers and streams would erode. Farms would fall back into nature. The plants we eat would start to disappear. Plus lots of corn, potatoes or tomatoes.
Farm animals would be easy prey for bears, coyotes, wolves and panthers. And the pets? Cats would go wild – that is, they would go feral, although many were preyed upon by larger animals. Most dogs wouldn’t survive either.
Like ancient Rome
A thousand years from now, the world you remember will still be vaguely recognizable. Some things would remain; it would depend on the materials they were made of, the climate they were in, and just luck. An apartment building here, a movie theater there, or a crumbling mall would be monuments to a lost civilization. The Roman Empire collapsed over 1,500 years ago, but you can still see remnants of it today.
If nothing else, the sudden disappearance of humans from the world would reveal something about how we treated the Earth. It would also show us that the world we have today can’t survive without us, and we can’t survive if we don’t care. To keep functioning, civilization – like anything else – requires constant maintenance.
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Carlton Basmajian, Associate Professor of Community and Regional Planning, Urban Design, Iowa State University
This article is republished from The Conversation under a Creative Commons license. Read the original article.