As usual the truth is somewhere in the middle.
fact 1. The earths climate is always changing, due to many factors from the suns activity, tectonic plate movement, the earths tilt etc. etc. as well as by biological organisms, anything from microbes, phytoplankton, and all the way up to humans.
fact 2. Humans have been influencing micro climates for at least 30,000 years due to practices such as slash and burn, deforestation, damming etc.
fact 3. Humans are certainly polluting the atmosphere with all sorts of gasses and particles, which at some point needs to be addressed and reversed if possible.
The problem occurs when ideologies, political point scoring, beliefs, righteous anger and noble cause corruption take precedence over the facts and practical scientific solutions.