Its CO2 and the sun which are the long term drivers of climate on earth. So when you say "humans" you're loading the question.
We know that global average temperatures have been relatively stable for the last few thousand years (you can see the error bars in this graph)
We can see from the industrial revolution say 1800's onwards on the graph directly above the temperature has risen rapidly.
We can also see solar irradiance has dropped over the last half dozen decades or so. So the Sun cannot be used to explain the recent warming.
So human activity of adding in CO2 has caused the warming. Cant believe that isn't self evident to you.
(20min delay)