Our world, without people?

[der_kluge]

I watched a movie on TV a long time ago which had this as its premise. It wasn't an A-list movie, by any means, and I don't remember the name of it. But, in that movie, there were just a handful of people left in the world. Like 3, I think, at least that was all that was in it. A black man, a white woman, and an older white man. In the end, the black man and the white woman went off to "repopulate", leaving the white guy all alone. In the final scene, you see him standing on a beach looking up at Saturn which was _huge_ in the sky.

I've often thought about this. And I think it's important to know the time of day *when* the event happens. Because if it happens at rush hour, there'd be millions of cars stranded on the highways.

 

[Driddle]

Ah. Thanks.

From my own experiences with a very, very small patch of my own front yard, it's easy to imagine that it wouldn't take much time at all for vegetation to destroy most of our roads. It only takes a small crack in the pavement, for example, for a seed to lodge. If it grows even a tiny bit, a small amount of dirt can accumulate and serve as an anchor for more plants. My entire sidewalk would disappear after just two seasons. And I've seen what a tree can do to a house's foundation when it's allowed to grow too big too close -- it is truly amazing how much strength a growing root can exert over long periods of time.

Climate and terrain would have varying effects on regions, of course.

 

[Hand of Evil]

Ah. Thanks.

From my own experiences with a very, very small patch of my own front yard, it's easy to imagine that it wouldn't take much time at all for vegetation to destroy most of our roads. It only takes a small crack in the pavement, for example, for a seed to lodge. If it grows even a tiny bit, a small amount of dirt can accumulate and serve as an anchor for more plants. My entire sidewalk would disappear after just two seasons. And I've seen what a tree can do to a house's foundation when it's allowed to grow too big too close -- it is truly amazing how much strength a growing root can exert over long periods of time.

Climate and terrain would have varying effects on regions, of course.

I would think that that roadways would be seen for a long bit of time, they may get covered but I would think in some place would still be used as herd trails.

Don't forget the effect of animal life, termites and beavers to name two. Beavers could have a interesting impact by flooding areas.

Makes you wonder how the animals would adapt and evolve.

 

[~Johnny~]

I've always thought this would be a fascinating setting for a world.

Not that it hasn't been done. Planet of the Apes is one example.

I've even thought of making a coffee table book about decay, that shows artists' interpretations of what the world would look like if we disappeared, stoping in at various places 500 years, 1000 years, and 10,000 years from now. How long would it take the last styrofoam cup to erode away? The problem is that I have neither the scientific background nor the artistic talent to make such a book.

 

[Hand of Evil]

How long would it take the last styrofoam cup to erode away?

Never! Those damn styrofoam 'pills' will be mined as a resourse million of years in the future by whatever comes next!

 

[MerakSpielman]

It depends heavily on the climate.

In desert or semi-arid areas, like where I live, the only reason trees and grasses can destroy patios and sidewalks is because we go through a great deal of trouble and expense to water them.

If people vanished from Albuquerque, most of the plants would just up and die from neglect and any open patch of ground would quickly revert to its natural state - dry, light brown earth with a few hardy plants. Most of the buildings would stay for quite a while - centuries easily - though of course they would be in a bad state of repair. It does rain enough for the roofs to collapse after a few decades, but the walls should stay around for a while, especially those concrete houses they built in the 50s.

Here is a picture of the American SW desert:

 

[Umbran]

The threads linked are pretty darned good, but perhaps putting some information here would be useful...

Exactly how long a thing lasts really depends upon the local weather conditions and the materials.

Dry climates are much more friendly to man-made objects than damp ones. Yearly freeze and thaw cycles are nasty to most structures.

Yes, there are 400 year old wooden structures in existance. However, I've yet to hear of one that was not attended and maintained for most or all of it's existance. Left unattended, in a temperate clime (with rain, snow, warm summers and freezing winters, the lifespan of a wooden structure is on the order of decades, not centuries or millennia.

Natural stone has a much longer lifespan than man-made concrete, in terms of weathering.

To give you an idea of roads - the interstate highway system came to be in the Eisenhower years. Note that mere decades later it is in constant need of repairs. Signs of the roads may be visible centuries later, but it won't be much of a road after a few decades (again, assuming temperate, climes with moderate rainfall).

 

[Vargo]

I watched a movie on TV a long time ago which had this as its premise. It wasn't an A-list movie, by any means, and I don't remember the name of it. But, in that movie, there were just a handful of people left in the world. Like 3, I think, at least that was all that was in it. A black man, a white woman, and an older white man. In the end, the black man and the white woman went off to "repopulate", leaving the white guy all alone. In the final scene, you see him standing on a beach looking up at Saturn which was _huge_ in the sky.

That was The Quiet Earth, but the trick was that the old guy abandoned the other two and killed himself to stop the rest of the world from being destroyed.

Weird film, I agree.

 

[physics_ninja]

To give you an idea of roads - the interstate highway system came to be in the Eisenhower years. Note that mere decades later it is in constant need of repairs.

Something that most people don't realize is that sunlight will cause asphalt to disintigrate. Without people to take care of and repair potholes our highway system would be utterly unusable within a decade.

 

[WayneLigon]

Let's assume that there's some kind of Marie Celeste effect: People simply vanish, leaving everything as it is right at this second. For simplicity's sake, we'll assume that at that second, there are no cars, busses, planes, trains, whatever in motion at the time.

One of the major things that will happen will be fires. Probably tens of thousands of them, everywhere people are, caused by something sparkling natural gas lines, gasoline storage, oil containers, unmaintained chemical processes, etc.

We can assume power will fail within a few days I think, since there's no-one to repair things or monitor processes or undo failsafe shutdowns, but until then you'll have falling power lines and innumerable powered items that will spark fires. If a major building fire is in progress, it will probably spread a great deal before it burns itself out. Some might not do that, if they reach chemical plants, oil refineries and the like. Depending on the time of year and the amount of rainfall, vast amounts of forest and acreage will burn uncontrolled and that will take care of a lot of the suburbs in places.

Fire should over, say, fifty years, take care of a lot of the city buildings since many that ordinarily would stand the test of time will be gutted, then fall over or fall in depending on the exact means of construction. Much of the incidental man-made pollution will also be taken care of since much of the styrofoam, rubber and plastic will also burn. It's residue will likely remain poisonous for decades.

Some cities will eventually vanish, since they require man's assistance to continue; New Orleans is probably a good example of this. The netherlands, probably. Anything below sea level that requires a wall or dam to keep back the sea can expect to flood within 50 years or so, I'd think, depending on the amount of wear from storms.

Flooding will also occur, further wiping out or burying many traces of man; without maintenance or oversight, I'm sure many of the larger dams will eventually burst. Flood control will be a thing of the past. Rivers will sweep away parts of cities and bury them in silt.

Storms will do tremendous damage. Many cities on the coast will suffer a great deal of wear and tear every year, depending on what the hurricane season is like. Tornadoes in the south and midwest will render some buildings down to splinters every year.

I don't know what the long term effects of areas that are currently built on inadequately-created landfill, but I'm guessing it's not good. Let's say that 200 years from now, everything built on landfill has sunken or fallen back into the sea.

Some areas will be rendered unlivable forever as nuclear power plants deteriorate and release waste (I doubt the pile will be exposed; unchecked, some might create a China Syndrome but some will probably just lie there dormant until some poor animal or human successor manages to crack open the unit), chemical waste disposal units crack and vent poisons into the water table, etc.

Real city-leveling earthquakes are very rare; the couple that might occur within, say, 200 years, will take care of leveling and burning some West Coast cities.

Many roads will be wide trails within two hundred years or so, as plants and weather effects crack and break apart the upper layers; poorly maintained roads deteriorate quickly. (but not as quickly as now in some cases; they won't be subjected to multiton stresses every few minutes). Many roadways in states that have regular deep winters probably will not fare as well. Bridges and overpasses will eventually fall from ice expanding and cracking the seals over and over again, a little bit more each year. Same with some buildings, once the glass breaks from shifting and the rain can get inside.

Many animals will die, of course. Many will revert to the wild. Some zoo animals will escape and breed, though it seems like many will simply die in their cages and moated areas. Some will get loose, though, and may or may not spread through the area depending on their dietary needs (I seem to remember that many zoo animals need some pretty specific things in their diet?), and the number that get loose. Most will probably die back after a few generations since there won't be enough, say, chimpanzees in an area to maintain needed genetic diversity. Some may find niches left wide open, and they will fit right in and adapt.

(I dunno, though; there are quasi-tame monkeys in Florida that got loose from movie shoots that seem to have done well for themselves; surely several monkey generations have passed since the Fifties and Sixties).