None of the above. It’s not a research paper, it’s from:
The Fifth National Climate Assessment
The Fifth National Climate Assessment is the US Government’s preeminent report on climate change impacts, risks, and responses. It is a congressionally mandated interagency effort that provides the scientific foundation to support informed decision-making across the United States.
Bill is quoting from Chapter 3 “Earth System Processes”, Section 4 " Humans Are Changing Earth System Processes", that begins by just stating the sources and causes of uncertainty in models. It doesn’t anywhere state or imply those uncertainties means any of the conclusions of the report are in any way wrong, unsupported, or improperly stated or otherwise.