Phase of two signals helps to indicate if the correlations you find may be in fact be causation.
And it raises interesting questions about if statistics or filters are the way to examine temperature data.
Take the UAH data which I refer to in https://climatedatablog.wordpress.com/2015/12/21/moved-to-dropbox/
What is going on with Oceans and Land?
Early in the data it shows the Oceans pushing the Land. Later the two are mostly in phase.
The Southern Hemisphere plot is interesting though. Recently the Land is in opposite phase to the Oceans. Now I would expect to see that indicate that some major event is about to happen. Phase opposition is often indicative of rapid change in the near future.
Up or Down? The traces do not say (yet).