This sort of speculation harms the argument for climate change more than it helps it. To convince others, it's better to build a case on scientific fact and large-scale issues than one specific interest of a likely-natural oddity.
You're being unfair. Speculation is how you create new hypothesis and it is perfectly ok as long as you don't confuse your hypothesis with a theory. (which GP did not)
This particular hypothesis seems to be invalidated by the fact that the phenomenon was observed before, back in 1895. See the wikipedia link in comment above.
As a response to whoever thinks ftvy was arming HN community by doing unreasonable speculation (and downvoted both our comments), let me quote the first, most upvoted comment on another thread, currently on the main page.
> I agree in part in that I am skeptical that full self-driving cars will happen in the next few years, but he is completely wrong when it comes to the long term. Not only will the tech get as good as humans, but most forget to account for the fact that the environment will meet the cars part way. [..]
As you can see, speculation is well accepted in the HN community. This is why I think spritecranberry's comment was unfair.
Oh, so since this is an isolated phenomenon that it is your preference to ignore this as evidence for your cause because it doesn't meet your criteria. That's not science either.
>This sort of speculation harms the argument for climate change more than it helps it.
What? Do you get mad at people for saying "it looks like rain"?