A global catastrophic risk is a hypothetical future event which could lead to the destruction
of modern civilization, mass extinction, or the destruction of the planet entirely.
Earth’s geological record is filled with asteroid impacts, climate shifts, ice ages,
super volcanoes, and extinction–lots of extinction; but the greatest risk to life
may not come from anything terrestrial.
Here are 10 of the most terrifying existential risks to life on Earth.
10.
Warfare and Weapons of Mass Destruction
In 1983, the Soviet Union’s nuclear early warning system reported the launch of multiple
USAF Minuteman intercontinental ballistic missiles from US military bases.
The only thing that saved us from having our skies bathed in nuclear fire, was officer
Stanislav Petrov’s gut feeling that the warning was a false alarm.
John F. Kennedy once estimated the odds of all out nuclear warfare happening to be “somewhere
between one out of three and even.”
American Cryptologist Professor Martin Hellman has claimed that nuclear war is inevitable.
The United States and Russia have a combined arsenal of 14,700 nuclear weapons, and the
total world supply ranges in the high 15,000s.
Though Cold War studies estimated that billions of people would survive the initial conflict,
the debate rages on whether or not secondary effects such as, nuclear winter, radiation
sickness due to fallout, and unforeseen environmental effects could contribute to the total extinction
of life on Earth.
A 2008 survey by the Future of Humanity Institute estimated a 4% probability of extinction from
warfare by 2100, with a 1% chance of extinction from nuclear warfare.
Other forms of warfare, such as biological and chemical warfare also carry their own
risks—though chemical warfare has a significantly lower chance of threatening life on Earth
as a whole.
9.
Biotechnological Disaster
In 2008, a survey made by the Future of Humanity institute estimated a 2% probability for life
on Earth to go extinct due to the accidental release of a biologically modified organism.
The increasing accessibility of technologies which allow us to modify the characteristics
of viruses and other biological agents has lead to an increased risk factor that such
agents could be accidentally released into our environment, having devastating effects
on eco-systems they come in contact with.
In 2001, researchers attempting to sterilize rats by developing a new virus accidentally
modified it instead.
The modified virus became extremely volatile to the mice, even to those that had already
been vaccinated.
Following the rapid developments in CRISPR editing (editing of DNA sequences found in
genomes of organisms like bacteria and archaea), an international summit proclaimed in December
2015 that it was “irresponsible” to proceed with human gene editing until safety measures
and efficacy could be addressed.
8.
Nanotechnology
In K. Eric Drexler’s 1986 book Engines of Creation, the nanotechnology pioneer outlines
a terrifying scenario where the accidental creation of nano-machines that consume organic
matter as a means of energy production end up devouring all life on Earth.
While this idea that such an event could be accidental has been rejected by modern day
experts in the field, there is still quite a bit of existential risk with the emerging
development of nanotechnologies.
While there is a plethora of benefits to the development of nanotech such as automation,
medical advancement, and manufacturing, there are also risks in those same areas.
It has been argued that the emergence of these technologies could lead to a new arms race.
Since nanomachines are so small, and factories of them could take up as little space as a
small desktop, it would be incredibly difficult for governments to regulate their use or production.
It has been noted that nanotech would be extremely beneficial in medical procedures, but the
same could be said of warfare.
Nanomachines would be capable of entering the bodies of enemy combatants or civilians
without their knowledge and be just as effective at killing the subject as they would be in
other medical procedures.
7.
Artificial Intelligence
Stephen Hawking, Elon Musk, and Bill Gates have argued that the rise of super intelligent
machines would spell certain doom for humanity; and it all comes down to control.
We’re already seeing automation take hold in many industries.
The robots that serve us may not be intelligent enough to pose a threat yet, but what happens
when A.I. surpasses human intelligence?
Would it see us as obsolete?
Would it seek to eradicate us?
Most of you are probably thinking of Terminator style machines or A.I. controlled drones hunting
humans down in the trenches of a post nuclear wasteland—and while that’s certainly a
possibility—the threat could take a very different form than what’s offered by Hollywood
science fiction films.
More and more systems are becoming automated, relying on basic A.I. to do rudimentary things.
What happens when this automation extends to medical equipment, or when computer viruses
become able to self-adapt to counter measures, or if super intelligent machines gain the
ability to build even greater artificial intelligences?
Science fiction author and computer scientist Vernor Vinge suggested that the moment when
humanity creates an intelligence greater than itself is the very moment when the human era
will end, calling it the Singularity.
6.
Mineral Resource Exhaustion
In the last decade, the price of helium has gone up more than 250%.
One of the world’s biggest supplies of the element, the Federal Helium Reserve, has seen
its supply gradually depleted over the course of the last decade, and it is estimated that
it will sell off its remaining supply by 2021.
Helium is used in vital medical technology, arc welding, and to pressurize liquid fueled
rockets, and while it’s one of the most common elements in the known universe, it’s
extremely rare on Earth.
Scientific data seems to suggest that humans are living far beyond the carrying capacity
of our planet.
In July 2015, the official United Nations World Populations Prospects was revised, stating
that the population would swell to 8.5 billion by 2030.
And as of February 2020, we are currently sitting at 7.7 billion people worldwide.
Due to the increased demands on the Earth’s resources accompanying the increase in population,
scientists and researchers suggest that it is not a matter of “if” but “when”
those resources will dry up.
5.
Natural Climate Change
It has been proposed that at one point in the distant past, ice covered the entirety
of the Earth, exterminating all life on the surface.
Causes suggested for this “snowball earth” have ranged from space clouds (dust and particle
clouds that could have at one point blocked out the sun), a lowering of greenhouse gases,
to a much dimmer sun.
Ice ages dominate the majority of Earth’s timeline.
Interglacial periods are dwarfed by long stretches of time where the ice sheets rule the surface
of the planet, and can be attributed to variations in the Earth’s orbit, diming and brightening
of the sun during its natural cycles and processions, as well as extraterrestrial events such as
cataclysmic bombardment by asteroids—which can drastically increase the Earth’s temperature.
The average duration of an interglacial period is around 10,000 years.
The last ice age was more than 11,000 to 17,000 years ago.
It’s worthy to note that a modern ice age would have a drastic effect on human civilization.
It would disturb many industries, shrink useable land for crops, and it’s possible that such
an event would cause civilization to implode entirely.
To exactly what extent, though, is debatable.
What isn’t debatable, however, is that if another snowball earth scenario were to happen
in modern times, all life on the surface of the Earth would go extinct.
4.
Extraterrestrial Invasion
While there is no current evidence to support the existence of extraterrestrial life, many
prominent astronomers and scientists (such as Carl Sagan) have suggested that it is highly
likely, and in 1969, the “Extra-Terrestrial Exposure Law” was added to the US Code of
Federal Regulations in response to the possibility of biological contamination resulting from
the Apollo program.
While unlikely, it is possible that if extraterrestrial life exists, it could find us, and invade
the Earth, thereby exterminating and replacing human life, stealing our resources, terraforming
the planet to serve its/their own needs, enslaving us, or destroying the planet altogether.
Stephen Hawking suggested that we should be wary about answering messages from potential
alien civilizations.
If such a civilization were to view us as inferior, and if they were far more technologically
advanced, there’s no telling what they might be able to do to us.
3.
Cosmic Threats
In April 2008, it was announced that two simulations of long-term planetary movement, one at the
Paris Observatory and the other at the University of California, Santa Cruz, indicate a 1% chance
that Mercury’s orbit could be made unstable by Jupiter’s gravitational pull sometime
during the lifespan of the Sun.
If this were to become a reality, the simulations suggested a collision with Earth could be
one of four possible outcomes.
And if that were to happen, then all life on Earth would be wiped out.
Period.
Last year, we took the first ever photo of a black hole at the center of galaxy M87.
And it’s theorized that smaller black holes are fairly common in the universe.
Recently, ALMA (Atacama Large Millimeter/submillimeter Array, a set of 66 telescopes scattered across
the Atacama Desert in northern Chile) thought they might have discovered a wandering black
hole about the mass of Jupiter in our galaxy.
It’s thought that wandering black holes are rare, but if such a black hole were to
wander into our solar neighborhood, the effects would be disastrous.
Then there’s the possibility of gamma ray bursts frying the Earth, vacuum decay causing
the conversion of our universe to a lower energy state at the speed of light—destroying
everything we love without any forewarning, massive solar flares or super storms that
could cook us, and inevitably, the gradual expansion of the Sun’s radius into a red
giant where it comes to dominate the sky and boil our oceans if it doesn’t consume the
planet entirely (luckily, that last one won’t happen for billions of years).
If that doesn’t make you feel like an insignificant piece of star dust, I don’t know what will.
2.
Asteroid Impact
66 million years ago, the Chicxulub asteroid slammed into the Earth, killing the dinosaurs
and causing the Earth’s global temperature to rise by 5 degrees Celsius, a change that
persisted for 100,000 years.
Recently, the Chelyabinks meteor exploded over Russia with a blast that was stronger
than a nuclear explosion, injuring around 1,200 people.
Scientists often describe our solar system as a “shooting gallery,” and it should
be no shock that NASA has discovered well over 15,000 documented near-earth objects.
The most troubling of these may be Atira asteroids, which is a class of asteroids which orbit
too close to the sun to be easily detected.
Such an asteroid, named LF-6 is a world ending object that has the fastest known orbit of
any object in the solar system.
Its orbit also intersects Venus’, and it is possible that interactions with Venus’
gravity could one day alter the asteroid’s orbit, sending it on a collision course with
the Earth.
What’s most terrifying about the possibility of an asteroid hitting the Earth is that there’s
no viable plan to divert or destroy a planet ender.
Nuclear weapons have, in the past, been proposed, but new research suggests that not only would
nukes be largely ineffective, but they could actually make the situation even worse by
breaking a massive asteroid into large chunks.
1.
Environmental Disaster
The Holocene extinction is the sixth mass extinction event, and it’s ongoing, measuring
the mass die offs of mammals, birds, amphibians, reptiles, arthropods, and plants, at a rate
of 100 to 1,000 times faster than previously established natural background rates since
the end of the last ice age.
Some of these mass extinctions have been attributed to the hunting patterns of early humans, as
they expanded their numbers, as the extinctions do match up with the steady growth of human
populations and the rise of the civilization.
However, there is some debate as to how much human hunting activity contributed to the
extinction of megafauna and massive land mammals like the Woolly Mammoth.
One of the contributing factors could be climate change and ocean acidification.
Ocean acidification is known as global warming’s ugly twin.
For nearly 200 years, the ocean has absorbed more than 150 billion metric tons of carbon
from human activities, resulting in a record lowering of the average PH level for ocean
waters.
Risks associated with more acidic oceans include the extinction of biologically diverse habitats
such as coral reefs, and marine life.
And then there’s colony collapse disorder.
Measured in the early part of the 21st century, CCD is a phenomenon that occurs when almost
all the worker bees in a colony vanish, leaving behind a queen, plenty of food, and a few
nurse bees to care for the remaining immature bees.
Bees help to pollinate 35% of the world’s food sources, and current estimates suggest
that 25% of bumblebees in the US are at risk of extinction.
Habitat loss, pesticide use, and disease are thought to be causing the decline.
Environmental disasters like these could very well be accelerating the mass extinction of
life on Earth, and scientists give us a decade to solve this problem before we cross the
point of no return.