It's a shitty situation,basically.
Ecologically, the Earth has a carrying capacity of 2 billion, not doing any harm to the Earth.
We have eight billion people and growing - and billions of food animals.
Humans and their food animals are the biggest group on Earth.
And they eat, and eat, and excrete, and excrete...
All those brown, decaying masses produces gasses.
And all religions on Earth promote eating animals. All priests are well fed and are against birth control - so no help there.
What can be done?
Food police in every city, weighing people and ticketing them.
Big tax breaks for vegetarians.
Turn excrement into new products-bedding, shoes,clothing,furniture, cars, houses, etc.
Houses of compacted excrement would be very ecological.