End of the World Cometh!
Robert Frost speculated about the world ending in fire or in ice. Which do you think is likely to end us all: meteorite, global warming, nuclear weapons, zombies, or the super flu?
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I generally don't bother with the Writer's Block stuff, but with all the Pig Plague Panic nonsense going down - why not?
If asked back in the early 1980's - my answer would be by a nuclear war. Today, things are considerably different. I see the 'end of civilization' coming from from an asteroid or comet. A large enough comet - say 10 kilometers will cause devastation on a planetary scale. But even much smaller bodies can lay waste to a city, region or continent. One a mile across (1.6 km) could easily destroy a continent, raise a tsunami over a mile high and literally cause civilization to collapse overnight. This is not a 'possible event' - it WILL HAPPEN, it's only a matter of "when". (And yes, we are overdue..).
But there are other 'end game' scenarios - including the Earth going a runaway greenhouse (Like Venus) in a billion years (GY) at the most. At ~ 5 GY, the Sun's core will become increasingly unstable, eventually leading to the Red Giant Phase and the heat death of the Earth.
And we aren't even talking about other astronomical goodies like supernova, Gamma Ray Bursts (GRB), rogue black holes and other even more exotic beasts in the universe.
Notice - no mention of global warming. I've always seen man's impact on the current trend as secondary, with fluctuations in the solar cycle the main driving force. A key thing to note - this is only a warm interglacial period, as the orbital/global continent/current/airflow -etc conditions haven't really changed since the onset of major continental glaciations 1.8 million years ago in the Pleistocene.
Nothing we have observed, let me emphasize this - NOTHING that has happened so far is *unique* and/or without precedent. Indeed, there are plenty of evidence of far greater climatic shifts in even shorter time spans. (Go ahead and challenge me - my PhD work was in isotope geochemistry and paleoclimatology. You will LOSE.)
It's ONLY extreme to our very limited measurement database and human experience.
So, how will the world end?
Poll The End of the World