Who knows, but it is possible he didn't use that word because it is rather technical and many people would not know what it meant.
I mean I don't like the guy either, but you can give him little benefit of the doubt.
If he's gonna claim (which he indirectly does by asserting that Pruitt is wrong) that he is knowledgeable enough about the actual science to be able to discriminate and evaluate all the technicalities and details therein and conclude that Pruitt is wrong in claiming the issues aren't settled, then he should use the friggin' word the science uses. Schatz doesn't know shit about the science. If he claims he does (and he does) the only way he could prove that to me would be a one hour debate, with no moderator, between him and one of the university professor "anthropogenic global warming deniers". We all know he will never do that, because... he doesn't know shit about the science.
If he thinks his constituents in Hawaii are too stupid he could take two sentences or 30 seconds to educate them about the terminology and then explain how he has changed Hawaii's education system so that it will produce fewer uneducated graduates than it currently does. Like that could happen while he kisses the butt of the teachers union (he voted against DeVos).
And, no, I won't give him any "benefit of the doubt". He is totally responsible for every utterance me makes, and more so ones he repeats, including the totally stupid ones such as the title of, and underlined sentence in, his email. He makes decisions that effect me, and I'm holding him totally accountable and responsible for those decisions and the consequences of them. When he publicly lies about issues ("97%...", "I support the Second Amendment, but...". etc., etc., etc.) I won't give him an inch. He doesn't deserve an inch. He's gonna be there for at least six more years doing stupid stuff, and it makes me sick.
By the way, the senate voted to invoke cloture today 54-46, and the final vote of the Pruitt confirmation will likely be tomorrow afternoon. As I wrote in another post several of the up-for-re-election-in-2018 Democrat senators from states won by Trump in 2016 have crossed over and are voting for the Republican nominees/legislation. In this case, again, Manchin and Heitkamp are voting for Pruitt, and Tester may do so. (Of course, Susan Collins betrays Trump and the party and will vote against Pruitt.) So... Schatz... suck it!