h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

...then again, perhaps one would not want to spoil the surprise, hopefully a pleasant one... If the demographic population pressure can be sustained without major conflagrations of warfare, thereafter, over the succeeding lifetime, the world should see the beginning of a slow and gradual healthy decline in world population.

...perhaps a betting pool on whether asteroid Apophis will miss the 'keyhole' on its next pass, inside isosynchronous altitude, Friday, April 13, 2029, which will put it on a collision course with the Earth on its next subsequent pass, curiously, Friday, April 13, 2036. Really, all that is just too pat for words. Almost as though some hebephrenic monster is planning a practical joke. The 'Great Goblin of Outer Space' strikes again? Or, perhaps God is giving the world a chance, waiting to see how the world demographic population increase crisis is handled.

...plans against the projected sea level increase for the 21st century? estimates vary from none, to comparatively mild, to a catastrophe of Biblical proportions. The world had one (mild) sea level increase incident during the 20th century, immortalized in California surfer legend as "Big Monday"... when everything leveled off it amounted only to one intertidal, the low tide mark had moved to where the high tide mark used to be, perhaps the answer to what happened to Canada's Mackenzie ice sheet, in terms of horizontal expanse, once the third most extensive permanent glaciation on Earth, but comparatively shallow. It isn't there anymore.

The world could still survive a collapse of civilization as late as Roman times, when the height of technology was still the water wheel.

Since the advent of nuclear age, civilization has become indispensable to world survival.

...other things to come, as yet unforeseen...