I don't know about 2017, but having a year that is not as hot as the last 2 years - both the hottest ever recorded -- is really not surprising.

edit: found it, 2017 was the warmest ever recorded year that was not an El Nino year and the third warmest ever.
Oh, and a record in the cat 5 hurricanes (highest amount in shortest time). AND the northest ever recorded hurricane (Ireland)

I guess you can see the general trend without knowing German.