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Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy

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On 5/23/26 12:14 PM, Brock McNuggets wrote:
> It really is a shame.
No, cRudey.

https://rogerpielkejr.substack.com/p/rcp85-is-officially-dead

The international committee responsible for the official scenarios that 
feed into climate modeling that are the basis for most projective 
climate research and the assessments of the Intergovernmental Panel on 
Climate Change (IPCC) has just published the next generation of climate 
scenarios.

Big news: The new framework has eliminated the most extreme scenarios 
that have dominated climate research over much of the past several 
decades — specifically, RCP8.5, SSP5-8.5, and SSP3-7.0. This is an 
absolutely huge development in climate science which will have lasting 
impacts across research and policy.

The future is not what it used to be.

Today’s post commends the researchers who have brought climate scenarios 
more in line with current understandings, but also raises some 
significant continuing issues with the scenarios.

Let’s get started . . .

The new scenarios come from the Coupled Model Intercomparison Project 
(CMIP) — a project of the World Climate Research Programme (WCRP), 
co-sponsored by the World Meteorological Organization, the International 
Science Council, and UNESCO’s Intergovernmental Oceanographic Commission.

Under CMIP, now in its seventh iteration, sits another little-known 
committee with responsibility for developing the scenarios necessary for 
earth system models to project future climate.1 That committee — called 
ScenarioMIP — just published the new scenario framework that will 
underpin the IPCC’s Seventh Assessment Report (AR7) and much of the 
research that it will draw upon.

In a paper released earlier this month, Van Vuuren et al. (VVetal26) 
introduce a new set of seven scenarios. The authors write of the 
obsolete high end emissions scenarios (emphasis added):

“For the 21st century, this range will be smaller than assessed before: 
on the high-end of the range, the CMIP6 high emission levels (quantified 
by SSP5-8.5) have become implausible, based on trends in the costs of 
renewables, the emergence of climate policy and recent emission trends.”

Read that again — The high end scenarios are Implausible.2

I disagree that the implausibility of the high-end scenarios resulted 
from the falling costs of renewables or the emergence of climate policy, 
but that is a debate for another day.

What matters today is that the group with official responsibility for 
developing climate scenarios for the IPCC and broader research community 
has now admitted that the scenarios that have dominated climate 
research, assessment, and policy during the past two cycles of the IPCC 
assessment process are implausible: They describe impossible futures.

Tens of thousands of research papers have been — and continue to be — 
published using these scenarios, a similar number of media headlines 
have amplified their findings, and governments and international 
organization have built these implausible scenarios into policy and 
regulation.

We now know that all of this is built on a foundation of sand.

What changed
The new CMIP7 ScenarioMIP framework offers seven scenarios spanning a 
range from “VERY LOW” through “HIGH.” The current naming convention 
drops the radiative-forcing target labels of the SSP era — there is no 
“8.5” scenario, and no “7.0” scenario, but as I’ll show below, each 
scenario has a radiative forcing level in 2100.

I ran the available new scenarios (HIGH, MEDIUM, LOW, and VERY LOW) 
through the FaIR calibrated and constrained ensemble that Sanderson and 
Smith (2025) used to characterize the CMIP7 set (FaIR v. 2.2.0 as 
described in their README file). I then ran each of the five tier-1 SSPs 
through the same emulator with identical parameters to ensure that the 
results are apples-to-apples. The full methodology, data, and code is in 
the appendix to this post.

The headline results follow.

CO₂ emissions: fossil fuels and industry, 2000–2100



The chart above shows fossil-fuel and industry CO₂ emissions for four 
CMIP7 scenarios alongside the five tier-1 SSPs and the two main 
reference scenarios from the 2025 IEA World Energy Outlook.

Note the massive gap between the new HIGH and SSP5-8.5. The new HIGH 
reaches 71 Gt CO₂/yr in 2100 — far below SSP5-8.5 at 128 Gt in 2100. 
Nothing in the CMIP7 set comes close to SSP5-8.5. The new HIGH also sits 
below SSP3-7.0 by about 9% in terms of cumulative emissions to 2100. 
Note also the gap between MEDIUM (solid yellow) and SSP2-4.5 (dashed 
yellow), which I’ll return to below.

Both of the most recent IEA near term scenarios — which run to 2050 — 
fall below MEDIUM and SSP2-4.5.

The table below compares the CMIP7 scenarios to their closest AR6 
analogues, showing that the overall range has constricted. The higher 
scenarios have come down and the lower scenarios have come up — except 
VERY LOW, which moved down.




2100 effective radiative forcing and end-of-century temperature
The table below lists AR6 and CMIP7 scenarios from highest to lowest 
2100 radiative forcing. The middle column shows the average global 
temperature change from an 1850-1900 baseline, under the climate 
emulator used by CMIP7. The right column shows the average temperature 
change for the SSPs as projected by the IPCC AR6.




See Methods appendix for details.
Interestingly, the projected 2080-2100 temperatures of the SSPs 
decreased from their AR6 values based solely on recent updates to the 
FaIR climate emulator.3 These changes resulted primarily from the 
updating of emissions trajectories from 2014 (used in AR6) to 2023 (used 
by CMIP7). The more moderate emissions trajectories resulted in lower 
projected end-of-century temperature increases.

The new CMIP7 HIGH is 0.9°C cooler than SSP5-8.5 in apples-to-apples 
terms (and 1.4°C cooler versus IPCC AR6), and 0.2°C cooler than SSP3-7.0 
(-0.6°C against IPCC AR6).

The implausibility of upper-end legacy scenarios is now official.

CMIP7 avoided repeating the past with SSP3-7.0
Last April I argued here at THB that the climate science community was 
on the brink of repeating the RCP8.5 mistake with SSP3-7.0 — which 
assumed a 2100 global population approaching 13 billion, well above any 
contemporary demographic projection and a five-fold expansion of global 
coal use. Neither assumption survives current understandings of 
demographics or energy systems.

I don’t know if anyone in CMIP or ScenarioMIP reads THB4 — if not they 
should! — but regardless, they wisely chose not to adopt SSP3-7.0 as the 
new HIGH scenario.

The new HIGH scenario sits at 6.7 W/m² in 2100 — below the SSP3 baseline 
7.0 W/m² — with 9 percent less cumulative fossil CO₂ through 2100. As 
I’ll discuss below, this is progress; it is partial but real.

But the new HIGH still sits well above the plausibility range that we 
identified in Pielke, Burgess, and Ritchie (2022). We found that of the 
 >1,000 scenarios in the AR5 database, the plausible subset centered on 
a median of ~3.4 W/m² in 2100, with an upper end near 6 W/m². The new 
HIGH scenario is well above that upper end.

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Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy zendejo <zd@no.here> - 2026-05-22 16:29 -0600
  Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy Brock McNuggets <brock.mcnuggets@gmail.com> - 2026-05-22 22:42 +0000
    Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy zendejo <zd@no.here> - 2026-05-23 09:14 -0600
      Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy phoenix <j63840576@gmail.com> - 2026-05-23 10:32 -0600
        Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy Brock McNuggets <Brock.McNuggets@gmail.com> - 2026-05-23 16:37 +0000
          Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy zendejo <zd@no.here> - 2026-05-23 10:47 -0600
            Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy Brock McNuggets <Brock.McNuggets@gmail.com> - 2026-05-23 16:55 +0000
              Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy zendejo <zd@no.here> - 2026-05-23 12:28 -0600
                Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy Brock McNuggets <brock.mcnuggets@gmail.com> - 2026-05-23 18:53 +0000
                Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy zendejo <zd@no.here> - 2026-05-23 14:08 -0600
                Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy Brock McNuggets <brock.mcnuggets@gmail.com> - 2026-05-24 01:05 +0000
                Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy Dietrich Von GassenHousen <Dietrich@ZyklonB.org> - 2026-05-24 01:58 +0000
                Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy zendejo <zd@no.here> - 2026-05-24 11:13 -0600
                Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy Brock McNuggets <brock.mcnuggets@gmail.com> - 2026-05-24 17:51 +0000
                Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy zendejo <zd@no.here> - 2026-05-24 13:13 -0600
            Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy phoenix <j63840576@gmail.com> - 2026-05-23 11:00 -0600
              Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy Brock McNuggets <brock.mcnuggets@gmail.com> - 2026-05-23 18:14 +0000
                Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy zendejo <zd@no.here> - 2026-05-23 12:32 -0600
              Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy zendejo <zd@no.here> - 2026-05-23 12:31 -0600
        Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy zendejo <zd@no.here> - 2026-05-23 10:41 -0600
          Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy Brock McNuggets <Brock.McNuggets@gmail.com> - 2026-05-23 16:54 +0000
            Re: Federal Prisons Are Beginning to Force Trans Inmates Off Hormone Therapy zendejo <zd@no.here> - 2026-05-23 12:27 -0600

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