100yrs ago there were 2 billion people in the world, now there are 8 billion people. When it's cold those people heat their houses, hmm maybe that's why it it ends up warmer? When it's hot people run their Air Conditioning, Air conditioners are just heat pumps that push the hot air outside, hmm that would make things warmer outside.
Much of the "Green Energy movement" is just people whom think they are doing good things for the environment. Think of it like the "Recycling movement", you know where most of that plastic goes that you grow in the recycle bin? Sure you feel like you are doing your part but most of it ends up in landfills, the ocean, or burnt filling the environment with plastic, and that doesn't even take into consideration what it took to make the plastic in the first place, or the chemicals that leach off from it often ending up in you body. Things like Ethanol used as fuel take's up crop land, burns up the valuable top soil, and still add pollutants to the air. Hydro power has been used as centuries but now the tree huggers are worried because a few fish can't reproduce, but we've had "renewable energy" for centuries so it's not all bad.
Worried about methane? Well it's more then just farm animals releasing that methane, the 8 billion people are also releasing methane. But the biggest danger is the melting of the permafrost that's releasing way more methane then the animals. Nature has gone thru many changes in the billions of years planet Earth has been around, somethings it can fix quickly, other things take hundreds, or even thousands of years to adjust to. One way nature may try to correct it's self is by balancing the population, however humans have found ways to avoid most of these solutions, but someday nature will come up with something humans can not control.
The methane is mostly coming from the rainforests and the new plant growth in the Artic. It always builds in the atmosphere right before a iceage.. Ice age takes thousands of years to get to where the glaciers get down into America. The polar glaciers and ice packs are melting but what they're not telling you is Antarctica is growing. The earth is at a .17 degree tilt towards the sun.