I've anecdotally but repeatedly observed a certain balance between temperatures in the two hemispheres. For example, early this year (2018), while Europe was under a late winter spell, weather here in Chile was a bit warmer than usual. Then, during this year's record temperatures in the northern hemisphere, the winter here appeared colder than normal. And just now, as temperatures are quickly plummeting in Europe, on cue central Chile is seeing a heat wave.
It is my impression that unusual temperatures on one hemisphere are often accompanied by opposite events on the other.
Is it possible that there is an overall energy equilibrium reflected by global temperatures?