"Ten years from now:
Business as usual continues; the human population peaks at 8.5 billion, liquid fuels production remains more or less level by the simple expedient of consuming an ever larger fraction of the world’s total energy output, and the annual cost of weather-related disasters continues to rise. Politicians and the media insist loudly that better times are just around the corner, as times get steadily worse. Among those who recognize that something’s wrong, one widely accepted viewpoint holds that fusion power, artificial intelligence, and interstellar migration will shortly solve all our problems, and therefore we don’t have to change the way we live. Another, equally popular, insists that total human extinction is scarcely a decade away, and therefore we don’t have to change the way we live. Most people who worry about the future accept one or the other claim, while the last chance for meaningful systemic change slips silently away.
A hundred years from now:
It has been a difficult century. After more than a dozen major wars, three bad pandemics, widespread famines, and steep worldwide declines in public health and civil order, human population is down to 3 billion and falling. Sea level is up ten meters and rising fast as the Greenland and West Antarctic ice caps disintegrate; fossil fuel production ground to a halt decades earlier as the last economically producible reserves were exhausted, and most proposed alternatives turned out to be unaffordable in the absence of the sort of cheap, abundant, highly concentrated energy only fossil fuels can provide. Cornucopians still insist that fusion power, artificial intelligence, and interstellar migration will save us any day now, and their opponents still insist that human extinction is imminent, but most people are too busy trying to survive to listen to either group.
A thousand years from now:
The Earth is without ice caps and glaciers for the first time in twenty million years or so, and sea level has gone up more than a hundred meters worldwide; much of the world has a tropical climate, as it did 50 million years earlier. Human population is 100 million, up from half that figure at the bottom of the bitter dark age now passing into memory. Only a few scholars have any idea what the words “fusion power,” “artificial intelligence,” and “interstellar migration” once meant, and though there are still people insisting that the end of the world will arrive any day now, their arguments now generally rely more overtly on theology than before. New civilizations are rising in various corners of the world, combining legacy technologies with their own unique cultural forms. The one thing they all have in common is that the technological society of a millennium before is their idea of evil incarnate." - John Michael Greer