In the original source study for that statistic, of the abstracts the authors surveyed, 2/3 did not take a position on human caused climate change. These abstracts, 65% of those considered, are not included in the 97% figure. Further, what the original authors, Cook et al., actually found in their 2013 paper was that 97.1% of the relevant articles agreed that humans contribute to global warming. That is not equivalent to saying that humans are the main contributors to observed global warming (since the Industrial Revolution).
An accurate reading of the actual 2013 source of that bogus statistic is: “Of the approximately one-third of climate scientists writing on global warming who stated a position on the role of humans, 97% thought humans contribute somewhat to global warming.” Hardly anything to get your knickers in a knot over.
The additional distortion climate alarmists use is that, by stating “97% of scientists …”, it assumes there is a list which comprises 100% of scientists. Clearly, no such list exists, rendering even the original 97% figure meaningless baffle-gab.