This time the climate models may be down for the count. Two recent papers independently demonstrate the models' inaccuracy. New confirmation that climate models overstate atmospheric warming Posted on August 25, 2020 by curryja | 31 comments by Ross McKitrick Two new peer-reviewed papers from independent teams confirm that climate models overstate atmospheric warming and the problem has gotten worse over time, not better. Continue reading → Two new peer-reviewed papers from independent teams confirm that climate models overstate atmospheric warming and the problem has gotten worse over time, not better. The papers are Mitchell et al. (2020) “The vertical profile of recent tropical temperature trends: Persistent model biases in the context of internal variability” Environmental Research Letters, and McKitrick and Christy (2020) “Pervasive warming bias in CMIP6 tropospheric layers” Earth and Space Science. John and I didn’t know about the Mitchell team’s work until after their paper came out, and they likewise didn’t know about ours. Mitchell et al. look at the surface, troposphere and stratosphere over the tropics (20N to 20S). John and I look at the tropical and global lower- and mid- troposphere. Both papers test large samples of the latest generation (“Coupled Model Intercomparison Project version 6” or CMIP6) climate models, i.e. the ones being used for the next IPCC report, and compare model outputs to post-1979 observations. John and I were able to examine 38 models while Mitchell et al. looked at 48 models. The sheer number makes one wonder why so many are needed, if the science is settled. Both papers looked at “hindcasts,” which are reconstructions of recent historical temperatures in response to observed greenhouse gas emissions and other changes (e.g. aerosols and solar forcing). Across the two papers it emerges that the models overshoot historical warming from the near-surface through the upper troposphere, in the tropics and globally. . . .
The conclusion: New confirmation that climate models overstate atmospheric warming Posted on August 25, 2020 by curryja | 32 comments by Ross McKitrick Two new peer-reviewed papers from independent teams confirm that climate models overstate atmospheric warming and the problem has gotten worse over time, not better. Continue reading → Concluding remarks "I get it that modeling the climate is incredibly difficult, and no one faults the scientific community for finding it a tough problem to solve. But we are all living with the consequences of climate modelers stubbornly using generation after generation of models that exhibit too much surface and tropospheric warming, in addition to running grossly exaggerated forcing scenarios (e.g. RCP8.5). Back in 2005 in the first report of the then-new US Climate Change Science Program, Karl et al. pointed to the exaggerated warming in the tropical troposphere as a “potentially serious inconsistency.” But rather than fixing it since then, modelers have made it worse. Mitchell et al. note that in addition to the wrong warming trends themselves, the biases have broader implications because “atmospheric circulation trends depend on latitudinal temperature gradients.” In other words when the models get the tropical troposphere wrong, it drives potential errors in many other features of the model atmosphere. Even if the original problem was confined to excess warming in the tropical mid-troposphere, it has now expanded into a more pervasive warm bias throughout the global troposphere. If the discrepancies in the troposphere were evenly split across models between excess warming and cooling we could chalk it up to noise and uncertainty. But that is not the case: it’s all excess warming. CMIP5 models warmed too much over the sea surface and too much in the tropical troposphere. Now the CMIP6 models warm too much throughout the global lower- and mid-troposphere. That’s bias, not uncertainty, and until the modeling community finds a way to fix it, the economics and policy making communities are justified in assuming future warming projections are overstated, potentially by a great deal depending on the model."
There is a new generation of climate models. They do not represent improvement. New climate models – even more wrong Posted on 05 Nov 19 by PAUL MATTHEWS • Leave a comment The IPCC AR5 Report included this diagram, showing that climate models exaggerate recent warming: If you want to find it, it’s figure 11.25, also repeated in the Technical Summary as figure TS-14. The issue is also discussed in box TS3: “However, an analysis of the full suite of CMIP5 historical simulations (augmented for the period … Continue reading → The IPCC AR5 Report included this diagram, showing that climate models exaggerate recent warming: If you want to find it, it’s figure 11.25, also repeated in the Technical Summary as figure TS-14. The issue is also discussed in box TS3: “However, an analysis of the full suite of CMIP5 historical simulations (augmented for the period 2006–2012 by RCP4.5 simulations) reveals that 111 out of 114 realizations show a GMST trend over 1998–2012 that is higher than the entire HadCRUT4 trend ensemble (Box TS.3, Figure 1a; CMIP5 ensemble mean trend is 0.21°C per decade). This difference between simulated and observed trends could be caused by some combination of (a) internal climate variability, (b) missing or incorrect RF, and (c) model response error.” Well, now there is a new generation of climate models, imaginatively known as CMIP6. By a remarkable coincidence, two new papers have just appeared, from independent teams, giving very similar results and published on the same day in the same journal. One is UKESM1: Description and evaluation of the UK Earth System Model, with a long list of authors, mostly from the Met Office, also announced as a “New flagship climate model” on the Met Office website. The other is Structure and Performance of GFDL’s CM4.0 Climate Model, by a team from GFDL and Princeton. Both papers are open-access. Now you might think that the new models would be better than the old ones. This is mathematical modelling 101: if a model doesn’t fit well with the data, you improve the model to make it fit better. But such elementary logic doesn’t apply in the field of climate science. . . . Even alarmist climate scientist and BDS-sufferer James Annan is scoffing at the paper’s claims, suggesting that it should say “UKESM1 does a great job at everything other than its primary function”.
Scientist’s Confession: Climate “Models Have “Serious Flaws”… Confident Others Will Speak Up On “Fraudulent Claims” By P Gosselin on 14. September 2019 Now in English… An eye-opener book by Japanese MIT climate scientist now partly available in English at Kindle. MIT climate scientist Dr. Mototaka Nakamura’s writes global warming data are “untrustworthy”, “falsified”. Image: http://iprc.soest.hawaii.edu/ Not long ago we reported on a recently released book authored by Dr. Mototaka Nakamura, a scientist who received his doctorate from MIT […]
RCP 6.0 and 8.5 are absurd, they are not even close to measured reality. They should be dropped permanently from any future modeling considerations as they are a complete waste of time and effort.
I find this kind of statement troubling. There is no problem with climate models per se. Some day, after hysterical anti-fossil-fuel CAGW nonscience has been universally recognized as a disgraceful fraud, hoax, and blot on the escutcheon of science, we will have accurate climate models. It would be more correct to say something more like, "Politically constructed climate models that grossly overestimate climate sensitivity to CO2 by wildly and baselessly overstating positive water vapor feedback are again proved hilariously inaccurate."
Unless you are aware of the fact that their primary function is to rationalize and justify hysterical anti-fossil-fuel hate propaganda.
". . . As an expert, Dr. Nakamura also believes that the climate simulation models used for climate change predictions have two “serious flaws” among many. One “fatally serious flaw” is the oceanic component of the models and the “grossly oversimplified and problematic representations of the atmospheric water vapor”. . . . "
Why can't that component ever be fixed? We are getting better oceanic data and more powerful analytical resources all the time. That is certainly a problem with current models, but why can't it ever be fixed?
Good thing corporate farmers don't listen to scientists' climate change scare tactics or we'd all be starving to death by now.
´ ~ It' too soon for another miscalculated disaster . I'm still trying to sell my Y2K generator, dehydrated food supply and gold coins !!
A case in point: UW Researchers Find Wildfire Smoke is More Cooling on Climate Than Computer Models Assume Charles Rotter A study of biomass burning aerosols led by University of Wyoming researchers revealed that smoke from wildfires has more of a cooling effect on the atmosphere than computer models assume.
That's self-evident, and one of several problems with them. But it's a problem with current models, not with climate modeling per se. I see no reason future models based on more accurate (and honest) assumptions, more comprehensive data, and greater computing power could not accurately model the earth's climate.
True. I'm not necessarily saying it will happen before the Singularity. It's possible that superhuman artificial intelligence is easier than modeling the earth's climate system.
