If humans become extinct, what will the earth look like a year later?

If humans were extinct, what would the earth look like a year later?

Nat Carlton Basmajian\ Associate Professor of Community and Regional Planning, Urban Design, Iowa State University

If humans were extinct, what would the earth look like a year later? – Essie, 11, Michigan

Have you ever wondered what the world would look like if everyone suddenly disappeared?

What will happen to all our stuff? What will happen to our homes, our schools, our neighborhoods, our cities? Who will feed the dog? Who will 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—that is, someone who helps cities plan what their communities will look like—sometimes it's my job to think about such possibilities.

If humans just disappeared from the world, and you could return to Earth to see what happened a year later, the first thing you would notice would not be seen by your eyes but felt by your ears.

The world will be quiet. Understand how much noise people make. Our buildings are noisy. Our cars are loud. Our sky is noisy. All this noise will stop.

You would notice the weather. After a year without people, the sky will be bluer, the air clearer. The wind and the rain would clean the surface of the earth; All the smog and dust that humans produce will disappear.

Imagine the first year, when your house was standing without anyone disturbing it. Enter the house - and let's hope you are not thirsty, because there will be no water in your taps. Water systems require constant pumping. If there is no one in the public water supply to manage the machines that pump water, then there is no water.

But the water that was in the pipes when they were all gone was still there when the first winter came - so in the first cold wind, the frozen air would freeze the water in the pipes and burst them.

There will be no electricity. The power plants will stop working because no one will monitor them and maintain the fuel supply. So your house will be dark, without lights, TV, phones or computers.

Your house will be dusty. In fact, there is dust in the air all the time, but we don't notice it because our air conditioning and heating systems are blowing air around. And when you move between the rooms, you make the dust continue to be in motion but as soon as all this stops, the air inside the house will be still and the dust will settle everywhere.

The grass in your yard will grow - and grow and grow until it is so long and flexible that it stops growing. Many plants you have never seen before will take root in your yard. Every time a tree drops a seed, a small seedling may grow. No one will be there to pull it out or cut it.

You would notice a lot more buzzing insects. Remember, people tend to do everything they can to get rid of bugs. They spray the air and the ground with bug sprays. They remove the insects' habitats. They put screens on the windows. And if that didn't work, they hit the bugs.

Without people doing all these things, the insects will return. They will once again have a free hand over the world.

On the street where you live there will be creatures that will look and wonder. First the little ones: mice, groundhogs, raccoons, skunks, foxes and beavers. North America was once rich in beavers.

Larger animals would come later – deer, coyotes and the occasional bear. Not in the first year, maybe, but eventually.

Without electric lights, the rhythm of the natural world will return. The only light will be from the sun, moon and stars. The creatures of the night will feel good about having their dark skies back.

Fires will occur frequently. Lightning can damage a tree or a field or even directly damage buildings. Without people to put them out, these fires will continue until they burn themselves out.

Across the city after only one year, the concrete materials - roads, highways, bridges and buildings - will look about the same, but if we go back, say, a decade later, they will have cracks and small plants will grow through them. This happens because the Earth is constantly moving. With this movement comes pressure, and with this pressure come cracks. Eventually, the roads will crack to the point where they look like broken glass, and even trees will grow through them.

Bridges with metal pillars will rust slowly. The beams and screws that hold the bridges will also rust. But the big concrete bridges, and the interstate roads (in the USA), also concrete, will last hundreds of years.

The dams and levees that people have built on the rivers and streams of the world will be eroded. Farms will return to nature. The plants we eat will start to disappear. There won't be much corn or potatoes or tomatoes anymore.

Farm animals would be easy prey for bears, coyotes, wolves and panthers. And pets? The cats will become feral, although many will be eaten by larger animals. Most dogs won't survive either.

Like ancient Rome

A thousand years from now, the world you remember will still be vaguely recognizable. Some things will remain; It will depend on the materials they are made of, the climate they are in, and just plain luck. An apartment building here, a movie theater there, or a crumbling mall will stand as monuments to a lost civilization. The Roman Empire collapsed more than 1,500 years ago, but you can see some remnants even today.

If nothing else, the sudden disappearance of humans from the world will reveal something about how we treated the planet. It will also show us that the world we have today cannot survive without us and that we cannot survive if we do not care about it. To keep it functioning, civilization - like everything else - needs constant maintenance.