In previous editions of the “Inhofe 400,” we found one skeptic whose only qualification for being a “climate expert” was to have written an op-ed and another who argues that climate change must not be happening because God would never allow it.

We also found some economists who don’t seem to doubt that humans are causing the climate to change.

Today’s “skeptic,” Prof. Christopher L. Castro, is a bonafide atmospheric scientist, so he clearly has relevant expertise on his resume.

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I emailed Prof. Castro about being on this list, and he replied:

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Since I’m asked about this often, my “official” position on global warming is given in my series of lectures I present in NATS 101 (accessible via my website link). You are free to quote my position from that if you like.

I went on his website and found these quotes from this lecture (MS PowerPoint file, slides 3 and 4):

Conclusion of 2007 IPCC:

It is very likely (90 percent) that anthropogenic activities have caused the observed warming over the past fifty years

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Your professor’s opinion
The conclusion of the 2007 IPCC is reasonable given the paleoclimate record, the available empirical evidence from the observed climate record, and agreement with global model results simulating the climate of the past 100 years.

Hmm. Doesn’t look like a skeptic to me.

Another one bites the dust. It’s enough to make you wonder whether Inhofe is making an honest argument.