system
Given the following post, respond as if you're commenting on Reddit:
human
[Avatar] What's the state of Earth?
gpt
In short: Overpopulated, not enough resources, polluted, bleak, dirty and depressing. 

They go into it in great detail in the original script of Project 880. Which is the original script by James Cameron that eventually turned into Avatar: 


It is a century from now, and the population of our tired planet has tripled. Finally, drowning in its own toxic waste, starvation and poverty, the population has topped out at a nice even 20 billion. The Earth is dying, covered with a gray mold of human civilization. Even the moon is spiderwebbed with city lights on its dark side. Overpopulation, overdevelopment, nuclear terrorism, environmental warfare tactics, radiation leakage from power plants and waste dumps, toxic waste, air pollution, deforestation, pollution and overfishing of the oceans, global warming, ozone depletion, loss of biodiversity through extinction... all of these have combined to make the once green and beautiful planet a terminal cess-pool.


Josh lives in the urban sprawl which has grown like kudzu over the whole eastern US. His particular part of this undifferentiated concrete rat- warren is Charlotte, NC, but you could be anywhere. Its the same crowded, gray, trash-strewn high-tech squalor. The walls are gray, the sky is gray... the people are gray. They shuffle past each other in dense crowds, shoulder to shoulder, unwashed because of the water shortages, and sickly looking from the bankrupt diet of cheap carbohydrates and synthetic proteins.


It looks like a cross between THX-1138 and a Calcutta train station. Josh has it a little worse than most because of his involvement in a stupid little war people barely remember. He is paralyzed from the waist down, and his useless legs hang twisted and shrunken down the front of his wheelchair. Josh still wears his army jacket, and with his unkempt beard and hair, and surly eyes, he is pretty much ignored by the crowds which buffet him like surf.


Just another angry vet, a piece of discarded human trash. Josh fights his way to work every day on the crowded subway. And every night he goes home to a tiny cubicle of an apartment in a vast government housing project. The room is reminiscent of a cell at a federal prison, which is pretty much what it is. The amenities look like they are from a 747, which is to say they are efficient, space conscious, and are about a hundred years old. There is a single fluorescent fixture, which casts a sterile light over the grimy walls. It flickers constantly.


One entire wall (all seven feet of it) is a TV screen. On it we get a wider view of the world, and it's nothing to write home about. There is a breaking story about a fire in a Boston subway which asphyxiated over a hundred people. Not unusual these days. This is followed by a feature about the death, in Kenya, of the last lion living outside captivity. This leads to a recap of the state of the environment overall, and it's grim.


The oceans are overfished and barren, poisoned by toxic runoff. All whales and at least half the Earth's fish species are extinct. On land over half the species extant at the beginning of the century are now gone forever, with most of the remaining endangered. The human race, using its technical ingenuity, has learned to keep itself alive, but it has lost almost all contact with the natural world, which it has strangled and crushed out of existence. There are no national parks left, only housing projects and protein farms. Yosemite is an upscale condo development. Most ocean-front property is used for mari-culture, since the only food source efficient enough to feed everyone these days is spirulina.