On the right hand side of that chart, it says he gets his data from both reconstructions and modern temperature measurements. How on earth are you supposed to compare those two? This is essentially just another hockey-stick graph.
Usually I like xkcd, but that one is wrong at the end. The data actually matches the "best case scenario" surprisingly well. I was really amazed at how that model has performed when I first saw it, it is really interesting.
https://tamino.files.wordpress.com/2014/03/gwpf_nasa-hansen_...
