The fundamental problem here is that the climate is a big system with many little systems operating inside it Within all of these systems there is always operating one huge simple negative stabalising feedback which is SrT So no matter how large a process is at providing positive feedback within the system  like icealbedo feedback say  the overall system remains stable except for quibbles like DO osc etc but even they are bounded Trying to define positive feedback by analogy with electronic circuits but forgetting that in those circuits only one feedback operates only leads to confusion