Apparently warming is compounded by the eruption, low sulphur shipping fuel rules, low amounts of Saharan dust and changes by El Niño according to this:
It would seem then that this year is yet another early warning sign. Perhaps we got lucky to get a glimpse of what is coming and in a sane world, this would motivate us to finally take real and significant action. Unfortunately, the last few years have demonstrated that we clearly don't live in a sane world and of course, we'll ignore this warning too.