The second order draft of the next IPCC report will be open for expert and government review from October 5th to November 30th. Sign-up to participate is already open. The application is online at:
https://sod.ipcc.unibe.ch/registration/
I’ll be signing up because I want to see if the second order draft has been modified in response to my thorough documentation of omitted variable fraud in the first order draft (“Vast evidence for solar climate driver rates one oblique sentence in AR5“).
The application is simple. It just asks for publications (I cite the blog posts I have written on my area of interest), and a brief statement of expertise (they don’t warn you, but this gets truncated at 750 characters).
Not sure if there is a sign-up deadline other than the closing of the comment window at the end of November. They only say that passwords will be sent out on October 5th. Could be you have to sign up before that. Good luck.