It is available online at http://www.sciencedirect.com/science/article/pii/S0921818113000891 (actually, it has been for a while, but I haven’t had much time for blogging lately!). For those of you who have already read this blog post, or the one at RealClimate by Rasmus, the contents should not be much of a shock. Sadly, the article is pay-walled, but if you don’t have university access contact me and I can see about getting you a copy. The code for the paper is available here.
Interestingly, I see that Mark Richardson of the University of Reading also has a comment on the Humlum et al. paper appearing online at Global and Planetary Change as well.