Coldest winter in southern australia what does it all mean, page-8

So, the model isn't broken

You just expect to see natural variation, so some parts of the world will be cooler at times. Simples.
Not that a 50 year cool is a particularly major record among over 100 years of data.

Warming is not exponential, certainly not at this stage. But do nothing and the curve is certainly expected to get steeper.