How have human and non human factors contributed to climate change and what evidence supports these factors?

Our climate has been in change since the planet formed... long before the first humans appeared. Volcanic outgassing and gas particles from space collected to form our atmosphere. Life began taking in some gasses and letting out others. This changed the ph of oceans and the gasses left over for life to use. On occasion, a large object will hit the earth or a large volcano will erupt, spreading ash and causing large areas to cool. Also, movement of tectonic plates has changed the areas where air and water currents circulate to and from due to solar heating. There's probably more, but, that should get you started. Cheers.