"There is overwhelming consensus in the national and international scientific communities that it is real and human greenhouse gas emissions are a major causal factor."

Overwhelming consensus is not scientific fact.  The climate is always changing.  Are human activities the major cause of changes to our climate?  The earth has gone through several ice ages where humans were not present.  What caused the warming and melting of the glaciers between these ice ages?  Could it be the sun going through cooling and warming cycles?