New paper by Lewis and Curry
Nic Lewis and Judith Curry have a new paper that’s just been published,
The impact of recent forcing and ocean heat uptake data on estimates of climate sensitivity
It’s in the AMS Journal of Climate, which is quite highly regarded, so well done them.
Nic has a blog post about it at Climate Audit, and there’s also an article at GWPF, New data imply slower global warming.
The paper adds to the already extensive recent literature showing that the climate sensitivity is most likely to be near the lower end of the IPCC range (1.5 – 4.5C). They conclude that climate models overestimate warming. The paper is paywalled but there is a preprint of the final version available here.
Here’s the abstract:
Energy budget estimates of equilibrium climate sensitivity (ECS) and transient climate response (TCR) are derived based on the best estimates and uncertainty ranges for forcing provided in the IPCC Fifth Assessment Scientific Report (AR5). Recent revisions to greenhouse gas forcing and post-1990 ozone and aerosol forcing estimates are incorporated and the forcing data extended from 2011 to 2016. Reflecting recent evidence against strong aerosol forcing, its AR5 uncertainty lower bound is increased slightly. Using a 1869–1882 base period and a 2007−2016 final period, which are well-matched for volcanic activity and influence from internal variability, medians are derived for ECS of 1.50 K (5−95%: 1.05−2.45 K) and for TCR of 1.20 K (5−95%: 0.9−1.7 K). These estimates both have much lower upper bounds than those from a predecessor study using AR5 data ending in 2011. Using infilled, globally-complete temperature data gives slightly higher estimates; a median of 1.66 K for ECS (5−95%: 1.15−2.7 K) and 1.33 K for TCR (5−95%:1.0−1.90 K). These ECS estimates reflect climate feedbacks over the historical period, assumed time-invariant. Allowing for possible time-varying climate feedbacks increases the median ECS estimate to 1.76 K (5−95%: 1.2−3.1 K), using infilled temperature data. Possible biases from non-unit forcing efficacy, temperature estimation issues and variability in sea-surface temperature change patterns are examined and found to be minor when using globally-complete temperature data. These results imply that high ECS and TCR values derived from a majority of CMIP5 climate models are inconsistent with observed warming during the historical period.
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I am sure Lew won’t approve and his mini-me, ATTP, will post some diversionary insincere pap to explain why Dr. Curry deserves to be roughed by the fellas.
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Beat me to it, Hunter.
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ATTP may possibly be insincere, but he sometimes engages. I’m very pleased when he does, since so few do, and his attempts demonstrate that all is not lost. Some people want to bridge the divide, in both directions.
One of our strongest arguments against the consensus is their lack of appreciation of scale. Twenty people die in a hurricane on some Caribbean island and they want to spend a trillion on retooling our society. Why not build a better hospital for Gaia’s sake? Articles like the Lewis & Curry one can only work in favour of sanity. But we need sane astrophysicists like ATTP on our side.
The article discussed here provides evidence for an estimate for climate sensitivity within the lower boundaries of IPCC figures. 1.5°C by the end of the century means no disappearance of island states, no billions of climate refugees. The first warmist who admits as much will make headlines. If it’s ATTP I’ll nominate him for a Nobel Peace Prize (though after Kissinger, Obama and Michael Mann, I’m sure he’d have the decency to refuse it.)
Based on your good word I will give ATTP the benefit of the doubt and oresumption that he wishes to engage in good faith in my comments going forward.
Geoff, Pity Ken Rice is South Africa otherwise he could already claim a nobel prize, like Michael Mann did with the IPCC
The new paper gets a story in the Express. Curiously the BBC and Guardian don’t seem to have covered it. There are only two typos as far as I can see in the bit I’ve quoted. (Yesterday the Telegraph’s education editor wrote a piece with four typos).
Climate change is ‘not as bad as we thought’ say scientists
CLIMATE change is likely to be markedly less severe than forecast, a study claimed yesterday
The study questioning the future intensity of climate change was carried out by American climatologist Judith Curry and UK mathematician Nick Lewis.
It is based on analysing the warming effect of greenhouse gases and other drivers of climate change, from the mid 19th century until 2016.
It forecast that future warming will be between 30 per cent and 45 per cent lower than suggested by simulations carried out by the UN’s Intergovernmental Panel one Climate Change.
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