Unless you are a climate scientist or have strong evidence suggesting that the whole field of climate science is incorrect, the points you make are, to be blunt, nearly completely irrelevant. Equally, the points I can make in return are also irrelevant. I have no idea how climate scientists estimate temperatures in 1900-1909, but I know they're not idiots: this is precisely the sort of factors they consider.
I think the debates for and against the AGW are so called mind killer.
I agree. Only two arguments are available against AGW: 1) Showing that the large majority of climate scientists do not actually support AGW, in fact, and 2) Showing that the whole field of climatology is incorrect in a strongly visible way that also allows us to see the direction of their biases. Arguing against AGW for any other reasons is irrational (not that I think these arguments are correct; just that they are the only arguments non-specialists can bring to bear on the issue).
Theism is often a default test of irrationality on Less Wrong, but I propose that global warming denial would make a much better candidate.
Theism is a symptom of excess compartmentalisation, of not realising that absence of evidence is evidence of absence, of belief in belief, of privileging the hypothesis, and similar failings. But these are not intrinsically huge problems. Indeed, someone with a mild case of theism can have the same anticipations as someone without, and update their evidence in the same way. If they have moved their belief beyond refutation, in theory it thus fails to constrain their anticipations at all; and often this is the case in practice.
Contrast that with someone who denies the existence of anthropogenic global warming (AGW). This has all the signs of hypothesis privileging, but also reeks of fake justification, motivated skepticism, massive overconfidence (if they are truly ignorant of the facts of the debate), and simply the raising of politics above rationality. If I knew someone was a global warming skeptic, then I would expect them to be wrong in their beliefs and their anticipations, and to refuse to update when evidence worked against them. I would expect their judgement to be much more impaired than a theist's.
Of course, reverse stupidity isn't intelligence: simply because one accepts AGW, doesn't make one more rational. I work in England, in a university environment, so my acceptance of AGW is the default position and not a sign of rationality. But if someone is in a milieu that discouraged belief in AGW (one stereotype being heavily Republican areas of the US) and has risen above this, then kudos to them: their acceptance of AGW is indeed a sign of rationality.