I've just made a Less Wrong / Alignment Forum post proposing that the AI safety research community standardize natural language terminology for describing probability ranges, by default adopting the IPCC's standard:
I didn't cross-post here, but it occurs to me that this might also be useful for EA writing, which also often needs to talk about probability ranges, especially when calculating impact.
See the post for details (~700 words). I'm not actively proposing it for EA writing, merely suggesting it for consideration, since I'm less involved in writing eg EA impact proposals.