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The claim of reduced uncertainty for equilibrium climate sensitivity is premature

Filed under: — rasmus @ 21 January 2018

A recent story in the Guardian claims that new calculations reduce the uncertainty associated with a global warming:

A revised calculation of how greenhouse gases drive up the planet’s temperature reduces the range of possible end-of-century outcomes by more than half, …

It was based on a study recently published in Nature (Cox et al. 2018), however, I think its conclusions are premature.

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  1. P.M. Cox, C. Huntingford, and M.S. Williamson, "Emergent constraint on equilibrium climate sensitivity from global temperature variability", Nature, vol. 553, pp. 319-322, 2018.

2017 temperature summary

Filed under: — gavin @ 19 January 2018

This is a thread to discuss the surface temperature records that were all released yesterday (Jan 18). There is far too much data-vizualization on this to link to, but feel free to do so in the comments. Bottom line? It’s still getting warmer.

[Update: the page of model/observational data comparisons has now been updated too.]

Forced Responses: Jan 2018

Filed under: — group @ 1 January 2018

This is a new class of open thread for discussions of climate solutions, mitigation and adaptation. As always, please be respectful of other commentators and try to avoid using repetition to make your points. Discussions related to the physical Earth System should be on the Unforced Variations threads.

Unforced Variations: Jan 2018

Filed under: — group @ 1 January 2018

Happy new year, and a happy new open thread.

In response to some the comments we’ve been getting about previous open threads, we are going to try separating out OT comments on mitigation/saving the planet/theories of political action from ones related to the physical climate system. This thread remains a place for climate science issues, questions, & news, but we have started a new Forced Responses thread where people can more clearly discuss mitigation issues. We realise that sometimes it can be hard to cleanly separate these conversations, but hopefully folk can try that out as a new year’s resolution!

Note we will be updating the Model/Data comparisons over the next few weeks as the various observational data sets get updated for calendar year 2017. The main surface temperature datasets will be released around Jan 18.

What did NASA know? and when did they know it?

Filed under: — gavin @ 24 December 2017

If you think you know why NASA did not report the discovery of the Antarctic polar ozone hole in 1984 before the publication of Farman et al in May 1985, you might well be wrong.

One of the most fun things in research is what happens when you try and find a reference to a commonly-known fact and slowly discover that your “fact” is not actually that factual, and that the real story is more interesting than you imagined…

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  1. J.C. Farman, B.G. Gardiner, and J.D. Shanklin, "Large losses of total ozone in Antarctica reveal seasonal ClO x /NO x interaction", Nature, vol. 315, pp. 207-210, 1985.