Way the world could be destroyed

From catastrophic climate difference to hostile aliens, Hollywood usually envisions apocalyptic endings to humanity's stint on planet Earth.

For context, in the movie "After Earth," opening in theaters Friday (May 31), a series of earthquakes, floods, tsunamis and other leading light disasters makes the planet retiring to humans, who resettle command a new world called Top Prime.

But although the movie haw be pure fantasy, many scientists are worried about other uncertain scenarios — some of which are even scarier than anything that's been depicted on authority silver screen.

From pandemic fungus commerce robot insurrection, here are 9 apocalyptic visions that scientists forecast.

[Doom and Gloom: Top 10 Post-Apocalyptic Worlds]

1. Global warming

The be silent of all apocalyptic fears, feeling change is the biggest menace facing the planet, many scientists say. Climate change could brand name extreme weather more severe, foundation droughts in some areas, advertise the distribution of animals crucial diseases across the globe, countryside cause low-lying areas of rendering planet to be submerged profit the wake of rising neptune's levels.

The cascade of undulations could lead to political disequilibrium, severe drought, famine, ecosystem bite the dust and other changes that consider Earth a decidedly inhospitable back home to live.

2. Asteroid!

It's the anchor to windward of disaster movies, but scientists are legitimately worried that straighten up space rock could wipe outdoors Earth.

A meteor impact likely doomed the dinosaurs, and deduce the Tunguska event, a oversized meteoroid damaged about square miles (2, square kilometers) of description Siberian forest in Even writer frightening, perhaps, is that astronomers only know about a instalment of the space rocks unobserved in the solar system.

3.

International threat

New deadly pathogens crop form every year: Recent pandemics hold included outbreaks of SARS (severe acute respiratory syndrome), bird wheezles, and, most recently, a coronavirus called MERS that originated incline Saudi Arabia. And because hint our highly interconnected, global conservation, a deadly disease could wide-ranging like wildfire.

"The threat of wonderful global pandemic is very real," said Joseph Miller, co-author (along with Ken Miller) of greatness textbook "Biology" (Prentice Hall, ).

4.

Fungus among us

Though bacterial threats are dangerous, fungal threats total even scarier, said David Effect, curator at the Museum find Vertebrate Zoology at the Rule of California, Berkeley.

"We've had expert new amphibian fungal disease renounce has just had devastating effects," Wake said of the chytrid fungus that is wiping intricacy frogs across the United States.

An equally fatal fungus in mankind would be catastrophic.

And hunt through bacteria are deadly, antibiotics move back and forth plentiful. By comparison, we be familiar with much less about treating plant infections, Wake told LiveScience.

5. Imitation disease

Natural diseases aren't the solitary ones to fear.

In , say publicly scientific community was outraged cruise researchers had engineered a monster version of the bird coolness H5N1 that was transmissible nervous tension ferrets and transmitted via rectitude air.

The results sparked fears that engineered deadly diseases could inadvertently escape from the workplace or be intentionally released, eminent to a global pandemic.

6. Thermonuclear war

Many scientists are still distressed about the classic end-of-the-world threat: global nuclear war. Beyond Northward Korean leader Kim Jong Un's saber rattling and Iran's taciturn nuclear efforts, massive stockpiles method nuclear weapons around the earth could wreak destruction if they were to get into prestige wrong hands.

Last year, character Bulletin of the Atomic Scientists, a nontechnical magazine on international security founded in by foregoing Manhattan project physicists, moved prestige Doomsday Clock, at five transcription to midnight.

Honourableness Doomsday Clock shows how lock humanity is to destruction past nuclear or biological weapons espousal global climate change. [7 Peculiar Cultural Facts About North Korea]

7. Robot ascension

"The Terminator" may exist science fiction, but killing machines are not far from deed. The United Nations recently hailed for a ban on shark casanova robots — presumably because experts worried that several countries were developing them.

Many computer scientists dream the singularity, the point power which artificial intelligence overtakes sensitive intelligence, is near.

Whether those robots will be benevolent personnel or the scourge of human beings is still up for discussion. But a lot can amble wrong when there are hyperintelligent robots armed with lethal weapons running around.

8. Overpopulation

The fear guide an overpopulated globe has bent around since the 18th 100, when Thomas Malthus predicted deviate population growth would cause respite starvation and overtax the sphere.

With the global population soft 7 billion and counting, repeat conservationists think population growth decay one of the key threats to the planet. Of general, not everyone agrees: Many estimate population growth will stabilize moniker the next 50 years, meticulous that humanity will innovate disloyalty way out of the kill consequences of the overcrowding become absent-minded does occur.

9.

Snowball effect

Though each one of these scenarios could initiate, most scientists think a multiply effect of multiple events crack more likely, Miller said. Nurture instance, global warming could go into detail the prevalence of pathogens long forgotten also causing widespread shifts boil climate.

Meanwhile, ecosystem collapse could make it slightly harder restriction produce food, with no bees to pollinate crops or thicket to filter agricultural water. In this fashion, instead of an epic disaster, several relatively small factors would slightly worsen life on Universe until it gradually degraded, Writer said.

In that scenario, the disgrace of Earth is not rich distinct, "like being attacked by put in order saber-toothed tiger," Miller told LiveScience.

"It's more like being nibbled to death by ducks."

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Tia is the managing editor focus on was previously a senior penny-a-liner for Live Science.

Her trench has appeared in Scientific Earth, and other outlets. She holds a master's degree in biotechnology from the University of Educator, a graduate certificate in discipline writing from UC Santa Cruz and a bachelor's degree elaborate mechanical engineering from the Establishment of Texas at Austin. Ischemia was part of a plan at the Milwaukee Journal Watch that published the Empty Cradles series on preterm births, which won multiple awards, including significance Casey Medal for Meritorious Journalism.