I've always shuddered rather when people say things like "70% of the observed temperature change is due to manmade carbon dioxide emissions". Christofides and Koutsoiyannis clearly feel the same way as shown in their presentation to the EGU a few days ago.
...we should be careful when we talk about causes, and that trends and shifts do not necessarily imply non-stationarity or a change in forcings: they can just happen.
The implications for all those claims of "we can only reproduce climate history with carbon dioxide in our forcing mix" seem rather profound.