Although the paper turns out to be uninteresting in the end, it's popular among climate skeptics, and I believe that thinking about what's wrong with it makes a good exercise in thinking about these issues. So, I do plan to blog about it.
I'm not trying to get anyone to check the DIFF12 calculation, because as far as I can tell the RealClimate people _agree_ with that. As far as I can tell, that's not the problem with this paper. Nonetheless I'm happy that some of you folks are checking this out, because it could be good practice for other things!
> So in short if RealClimate which critizes the Humlum et al paper gets the same Diff12(CO2) curve then something (at least for me)
unexpected happens and I would like to understand whats going on.
The graphs in the Humlun paper were surprising to me when I first saw them... but the [RealClimate post](http://www.realclimate.org/index.php/archives/2012/09/el-ninos-effect-onco2-causes-confusion/) explains why this effect occurs... and then the surprise disappeared. If I were smarter, or more of an expert, I wouldn't have been surprised for as long as I was! But I suspect a lot of nonexperts will be surprised at first - and that's why this can make a good educational blog post. With luck, I can do a better job of explaining to nonexperts what's going on than the RealClimate post did.