In this talk I will provide highlights of two different - but overlapping - research topics. Both relate to the processes that drive surface temperature variability.

In the first part I will focus on the role of ocean dynamics in driving sea-surface temperature variability. The key conclusion is that ocean dynamics act - in the net - to damp rather than drive low-frequency SST variability. The upshot is that the observed decadal variability - such as that associated with Atlantic decadal variability and the Pacific Decadal Oscillation - can not be traced to ocean processes.

In the second part I will focus on changes in temperature persistence under climate change. Here the key finding is that temperature persistence is certain to change across the globe, but that the signs of the changes depend critically on various physical processes. I will argue that one key but overlooked process is the changes in radiative damping timescales under climate change.