Search Results for: nic lewis

New Nic Lewis Paper

Nic Lewis’s paper on climate sensitivity is available. See his BH post here. Also see discussion at Judy Curry and WUWT.

Nic Lewis on Statistical errors in the Forest 2006 climate sensitivity study

Nic Lewis writes as follows (see related posts here, here) First, my thanks to Steve for providing this platform. Some of you will know of me as a co-author of the O’Donnell, Lewis, McIntyre and Condon paper on an improved temperature reconstruction for Antarctica. Since then I have mainly been investigating studies of equilibrium climate […]

Nic Lewis on Forest et al 2006

Myles Allen recently asked that more attention be paid by critics to work on climate sensitivity, rather than paleoclimate. Nic Lewis, a coauthor of O’Donnell et al 2010, has been parsing climate sensitivity calculations for some time and with considerable frustration. Nic Lewis has a very important article at Judy Curry’s here. One of the […]

Nic Lewis on IPCC Climate Sensitivity

Nic Lewis (a co-author of O’Donnell et al 2010) is a very sharp analyst who’s recently taken an interest in climate sensitivity estimates and has an interesting guest post at Judy Curry’s today. In his studies, he noticed that the IPCC’s representation in AR4 Figure 9.20 of the probability distribution for climate sensitivity arising from […]

Was early onset industrial-era warming anthropogenic, as Abram et al. claim?

A guest post by Nic Lewis Introduction A recent PAGES 2k Consortium paper in Nature,[i] Abram et al., that claims human-induced, greenhouse gas driven warming commenced circa 180 years ago,[ii] has been attracting some attention. The study arrives at its start dates by using a change-point analysis method, SiZer, to assess when the most recent […]

Gregory et al 2019: Does climate feedback really vary in AOGCM historical simulations?

A guest post by Nic Lewis Introduction The recent open-access paper Gregory et al 2019 “How accurately can the climate sensitivity to CO2 be estimated from historical climate change?” discusses, inter alia, the use of regression to estimate historical climate feedback. As I wrote in a previous article, Gregory et al. consider a regression in […]

Gregory et al 2019: Unsound claims about bias in climate feedback and climate sensitivity estimation

A guest post by Nic Lewis The recently published open-access paper “How accurately can the climate sensitivity to CO2 be estimated from historical climate change?” by Gregory et al.[i] makes a number of assertions, many uncontentious but others in my view unjustified, misleading or definitely incorrect. Perhaps most importantly, they say in the Abstract that […]

The impact of recent forcing and ocean heat uptake data on estimates of climate sensitivity

A guest post by Nic Lewis Judith Curry and I have now updated the LC15 paper with a new paper that has been published in the Journal of Climate There has been considerable scientific investigation of the magnitude of the warming of Earth’s climate by changes in atmospheric carbon dioxide (CO2) concentration. Two standard metrics […]

Emergent constraints on climate sensitivity in global climate models, Part 3

The two strongest potentially credible constraints, and conclusions A guest post by Nic Lewis In Part 1 of this article the nature and validity of emergent constraints[1] on equilibrium climate sensitivity (ECS) in GCMs were discussed, drawing mainly on the analysis and assessment of 19 such constraints in Caldwell et al. (2018),[2] who concluded that […]

Emergent constraints on climate sensitivity in global climate models, Part 2

The four constraints that Caldwell assessed as credible A guest post by Nic Lewis In Part 1 of this article the nature and validity of emergent constraints[i] on equilibrium climate sensitivity (ECS) in GCMs were discussed, drawing mainly on the analysis and assessment of 19 such constraints in Caldwell et al (2018; henceforth Caldwell),[ii] who […]