/sci/ - Science & Math

Uninformed plebeian here

My question is a simple but fundamental one:
have the IPCC or any other reputable scientists been able to ascertain the amount of warming in the last century that can be solely to attributed to humans?

From what I've heard in the media etc. humans have 'significantly' contributed to the rise in surface temps and heat. But how much is this significant contribution, do they give a percentage with uncertainty? is it 50%, 80%, 100% and how do we know?

Plus what's the best source to understand the science of AGW decently, is the IPCC physical science basis the best or too dense for a non-climatologist