Climate models have provided an avenue for studying the possible changes in extreme temperatures in the future; and in this respect, to ease of comparison across models from different modelling groups worldwide, the World Climate Research Programme (WCRP) established the Coupled Model Intercomparison Project (CMIP), which is devoted to providing standardized climate simulation outputs for intercomparison purposes.
Abstract. An analysis is presented of he disconnection between the CMIP5 and CMIP6 Historical and Future periods when considering the relationship of the individual model GMST changes and the climate sensitivity. I have included a simple model that can account for the period disconnection using the negative forcing of aerosol/cloud effects in the Historical period that is carried forward into the Future period. I attribute some of the uncertainty in simulations of this simple model to endogenous model decision (selection) uncertainty that leads to variations in the changes of the negative forcing in the Historical period carried forward into the Future period.
I note that Earth Systems Dynamics published the paper despite one of the two peer reviewers recommending against acceptance without further major revisions. But neither of the reviewers appear to have raised the issue that I focus on here.
Contrary to popular perception, the U.S. Midwest has seen little long-term summer warming. For precipitation, the slight drying predicted by climate models in response to human greenhouse gas emissions has not occurred; if anything, precipitation has increased.
Reposted from Dr. Roy Spencer’s blog February 6th, 2020 by Roy W. Spencer, Ph. D. Well, as I suspected (and warned everyone) in my blog post yesterday, a portion of my calculations were in error regarding how much CO2 is taken out of the atmosphere in the global carbon cycle models used for the RCP…
Reposted from Dr. Roy Spencer’s Blog February 5th, 2020 by Roy W. Spencer, Ph. D. Note: What I present below is scarcely believable to me. I have looked for an error in my analysis, but cannot find one. Nevertheless, extraordinary claims require extraordinary evidence, so let the following be an introduction to a potential issue…
By Rud Istvan, edited by Charles Rotter WUWT reader Max alerted us to a 1994 Naomi Oreskes et. al. paper published in the prestigious journal Science. Her paper was a critical analysis of Earth Science numerical models. I asked Rud to take a look, since he had previously written on climate models both here and…
From Dr. Judith Curry’s Climate Etc Posted on December 20, 2019 by niclewis | 14 Comments By Nic Lewis In an earlier article here I discussed a Comment on Lewis and Curry 2018 (LC18) by Kevin Cowtan and Peter Jacobs (CJ20), and a Reply from myself and Judith Curry recently published by Journal of Climate…
Reposted from Dr. Roy Spencer’s website October 25th, 2019 by Roy W. Spencer, Ph. D. NOTE: I have written on this subject before, but it is important enough that we need to keep thinking about it. It is also related to the forcing-feedback paradigm of climate change, which I usually defend — but which I…
12 October 2019 Pat Frank A bit over a month ago, I posted an essay on WUWT here about my paper assessing the reliability of GCM global air temperature projections in light of error propagation and uncertainty analysis, freely available here. Four days later, Roy Spencer posted a critique of my analysis at WUWT, here…