If you look at the recent rash of posts on climate change, you see some patterns: - The posts tend to focus on the idea of conspiracy rather than on climate sc

If you look at the recent rash of posts on climate change, you see some patterns: - The posts tend to focus on the idea of conspiracy rather than on climate science. - The articles posted tend to be from fringe sources, or popular news sources that skim the technical details - The postings tend to cluster, with frequent posts that are nearly duplicate. People posting out of honest interest on HN tend to focus on the technical and scientific; not always, of course, but you'd expect to see more technical posts than conspiracy posts on climate change, and that's not what we're seeing. They also generally post articles from scientific or technical sources: after all, if we just wanted to read nontechnical news, we'd look elsewhere. Finally, bona fide posters generally avoid posting duplicates---again, not always, but astroturfed posts naturally tend toward duplication because the whole point is to keep the topic in view at all times. Given the sustained presence of all of these warning signs, I think it's safe to say there's some astroturfing going on here.