Another systemic misuse of the RCP scenarios involves using RCP8.5 as a reference scenario and the others as mitigation scenarios in impacts, economic or policy studies
RCP creators warned against doing this when RCPs were created
But it is found everywhere, including IPCC
Scenario experts foresaw that this type of misuse was getting baked into the RCP methodology, drawing 4 scenarios from different models and renaming them as if they were comparable (when they weren’t)
The desire for RCP pathways of radiative forcing overrode considerations of the proper use of scenarios for impacts, economics, policy research
The perceived needs of climate modeling were explicitly expressed as the priority
So we have 1000s of studies with RCP8.5 as a reference scenario & RCP4.5 as policy success (as well as 2018 US Nat Climate Assessment)
These are (sorry) pretty much worthless
RCP8.5 is implausible
RCP4.5 is not policy success, closer to a worst case in fact
Every day I continue to be amazed that no one in leading institutions of the climate community (notably IPCC) has any responsibility for the evaluation of scenario plausibility
This is a huge oversight
Why does scenario misuse occur?
Because we allow it to occur
We now have 5 papers on scenario plausibility & other folks publishing as well
As you’ve seen this topic is a hot one, bc it implicates much past research as flawed, undercuts use of implausible scenarios in policy (eg, SCC) & suggests greater accountability for climate science
It is much easier for a few to dismiss this work as absurd, misleading, pointless and to call me a jerk than to confront the major issues at play here
But that’s OK, there is a growing and I think unstoppable recognition of these issues
🧵
Why are climate scientists so mad at me?
Here's one answer
For almost 30 yrs I've been writing abt the conflicts between (a) the special interests of the climate science community and (b) the broader social responsibilities of this community
Pretty normal STS fare ... read on
My 1994 PhD dissertation was an evaluation of the then newly-created US Global Change Research Program link.springer.com/content/pdf/10…
I argued that the USGCRP would do a lot of good science but have limited policy relevance (a conclusion later reached by a @theNASEM study)
I was a post-doc at NCAR when this paper came out
It resulted in a furor
NSF funded NCAR & the program officer who oversaw NSF funding was central to creation of USGCRP
My job was threatened
A huge debate ensued
UCAR leaders pushed back on the pressure
I kept my job
A preview...
Scenario misuse in climate science is far deeper and nuanced than semantics of reference scenarios (as some would have us believe)
They are also very pedestrian mistakes, common to efforts to use scenario methods in research
Not surprising or unique to climate, but significant
The petulance, name-calling and invented quotes we saw earlier today suggests that our first recommendation won't be easily taken😉
Easier to attack messengers than hear their messages
We all all suffer the consequences when science gets off track and some try to keep it there
The responses I've had today the this discussion have me optimistic that the powerful few gatekeepers in the climate space of 2009 are not so powerful in 2021
The teeth gnashing & name calling remains the same, but most now see it for what it is, and that's good news
Schmidt's refusal to acknowledge the incredible work @jritch and focus on me suggests that this is once again more of a personal issue he has with me than anything else
That would explain why his letter pretty much agrees with & acknowledges our claims while posturing otherwise
🧵 @ISSUESinST several climate scientists & Marcia McNutt (@theNASEM pres) respond to @jritch & my recent article on misuse of climate scenarios, offering a unified defense of RCP8.5
With the IEA now projecting a near-term emissions trajectory <RCP4.5 I've been taking a peek at the gatekeeping on RCP8.5 debates over recent years
A rich vein to explore
Really remarkable public evidence of how scientific progress gets stunted by a few powerful people
Examples
Despite @bradplumer recognizing implausibility of RCP8.5 in 2017 (props!) the NYT has apparently never written anything critical about the misuse of the scenario (my NYT search finds only 6 articles that explicitly mention RCP8.5 or "RCP 8.5")
With powerful figures Mann & Hayhoe (they weren't alone) warning critique of RCP8.5 is "denial," no wonder it has taken so long for researchers and journalists to deem its discussion to be legitimate
What's the difference between a for-profit climate analytics firm & a non-profit one, both living off of RCP8.5? 🤷♂️
I'm all for people making good money
Especially when they have paying clients for their services
But non-profit expectations are (and should be) different
Don't even get me started on sports organizations!