About 6,000–8,000 years ago, our not too remote ancestors experienced a period of rapid global warming, much more drastic than our most extreme predictions now. There was no fossil fuel industry then. What caused that global warming burst? What is the science behind an assumption that what we observe now is not the continuation of the glaciers retraction that started about 20,000 years ago and still progresses with periods of slower and faster changes?
If you follow the money, you will find out that scientists questioning the findings of IPCC are not getting any funding.
Lastly, assuming that they are right, read my comment again: “A human can easily trigger an avalanche, but it is beyond human power to stop its destroying power.” Our major disagreement is not about who caused it but what is reasonable to do now. A hint, spending the money we do not have is not a good idea.