Nine of the 10 warmest years on record have occurred since 1998. But forget individual years. That data is noisy. A single year can see its temperatures rocket for reasons having little to do with climate change.
Look, instead, at decades. There, the data is a little clearer, as the idiosyncrasies of any one year are balanced by its nine compatriots. That's exactly what the World Meteorological Association did in a recent report. Here's the graph: