Thread by @RogerPielkeJr

The IPCC is important & if it didn't exist we'd have to create it

Assessments of existing literature are useful
There should not be any new science in the assessment that isn't in the literature already

But I get the excitement of an embargo & prospects for textual exegesis🔥

https://twitter.com/IPCC_CH/status/1423626453850234883

There has always been a tension in the IPCC (and more generally in advisory processes) between

A. enabling or empowering decision makers to make decisions

VS

B. compeling decision makers to make particular decisions favored by assessors

See below⬇️

https://twitter.com/WMO/status/1423658071088369671?s=20

The IPCC has tried unsuccessfully to skirt the advocacy vs assess issue by invoking a phrase "neutral, policy relevant but not policy prescriptive"

This claim has been studied, critiqued and discussed in depth - such as, jstor.org/stable/44732800

The IPCC is an expert body, representative in many ways of the inequities in the fields that it covers
It has gotten better, but remains predominantly white, male, north, rich

mdpi.com/2225-1154/9/6/…

The IPCC is not a "science arbiter" in the sense of assessing an independent literature(s) because the IPCC has also overseen the creation of that literature (even going so far as to justify the creation in terms of making assessment easier)
doi.org/10.1016/j.erss…

The IPCC is in a bit of a pickle bc the scenarios that underpin literature on projections assessed by WG1 are, undeniably, out of date

These scenarios actually come from WG3 starting in 2005 & even earlier

So the 2021 WG1 report is really a look back, not current understandings

For those who know the literature, more important is how the IPCC frames, includes, ignores, emphasizes, deemphasizes this or that set of studies

The AR4 (mostly WG2) got into some trouble for spinning too much, leading to major reforms of the IPCC via IAC

AR5 was much better

There will be more to say when the report is out next week!