wicked, rubik-like, or zombie-ish?

In his book Why We Disagree about Climate Change,  the scientist Mike Hulme discusses climate change as a 'wicked' problem, by which he means that it's complex, unique and some solutions can make it worse.

Later Hulme was on the radio comparing climate change to a rubik cube, by which he meant it would be a much easier problem to solve if the interlocking issues were unpicked and dealt with separately.

 

And then earlier this month, as Kellie Payne reports in her blog yesterday, Hulme described climate change as a 'zombie concept'. What exactly is that? Would you recognise a zombie concept if it rose up from the dead? My guess is that it would look like:

 

a) an idea that's over, that's exhausted, and is therefore useless

b) an idea that keeps renewing itself, taking on new shapes, acquiring new identities, and is therefore useless

c)  an idea that gathers up too many other ideas within it, and is

therefore useless.

Have I missed anything out?