Well, first things first, this isn't an official Senate release or statement, despite what it says; this is completely Inhofe's doing (notice it says "Inhofe Press Blog" above it), who gets paid millions by oil and chemical companies to say climate change is false and compare people who believe in climate change to Nazis.
Secondly, I think you're reading
way too much into this. If you have a look at this article again, you'll see that a lot of those quoted scholars aren't saying that anthropogenic global warming isn't a fact; a lot of them are saying, "Nobody can be 100% sure." Look at Dr. John Maunder's quotes: he states no conclusions regarding mankind's impact on global warming but merely states that some climates may be beneficially impacted by it (while also acknowledging that others will be negatively impacted).
Overall, however, the underlying problem with this latest batch of silliness, is really the same as the problem with every other global warming denier argument: it offers
no compelling alternative explanation for what is happening. Today it's intelligent design and global warming; yesterday it was smoking and cancer; go back further, and it was germ theory of disease or doubters of the Copernican model. It's all the same: the deniers either have nothing, or a really obviously bogus "explanation" for what is observed. I know skeptics take umbrage at being grouped with such groups, but I'm afraid that's not my fault. These really are the historically comparable "debates" and this is how the climate skeptics will be viewed by history.
So for climate change, if man isn't causing it, what is? We have ruled out volcanoes, sun cycles, and other non-anthropogenic sources of GHGs (cows count as man-made here, considering the manner in which we've mass-produced them). Saying "it's natural cycles" is just punting the question. Natural cycles don't happen in a vacuum either and have proximate and measurable causes. A meteor strike killing the dinosaurs is "natural" but also it is not mysterious. So if the earth is warming for non-human caused reasons, what are they? Scientists have looked, and they're not finding them. The glaciers didn't just decide to melt a couple years ago. The ocean currents didn't mysteriously change and pump warm water into the northwest passage.