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The Crank Shaft

Filed under: — group @ 11 March 2019

This is a thread for collecting the oddball theories, tinfoil hat level conspiracies and other climate-related nonsense in the comments that would otherwise derail substantive discussion. Keeping them all in one spot might be of interest to future researchers.

Unforced variations: Mar 2019

Filed under: — group @ 3 March 2019

This month’s open thread on climate science topics.

The best case for worst case scenarios

The “end of the world” or “good for you” are the two least likely among the spectrum of potential outcomes.

Stephen Schneider

Beware the worst case scenario

Scientists have been looking at best, middling and worst case scenarios for anthropogenic climate change for decades. For instance, Stephen Schneider himself took a turn back in 2009. And others have postulated both far more rosy and far more catastrophic possibilities as well (with somewhat variable evidentiary bases).

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  1. S. Schneider, "The worst-case scenario", Nature, vol. 458, pp. 1104-1105, 2009.

Update day

Filed under: — gavin @ 7 February 2019

So Wednesday was temperature series update day. The HadCRUT4, NOAA NCEI and GISTEMP time-series were all updated through to the end of 2018 (slightly delayed by the federal government shutdown). Berkeley Earth and the MSU satellite datasets were updated a couple of weeks ago. And that means that everyone gets to add a single additional annual data point to their model-observation comparison plots!

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Forced Responses: Feb 2019

Filed under: — group @ 1 February 2019

A bimonthly thread on societal responses to climate change. Note that there is another open thread for climate science topics. Please stick to specifics as opposed to arguments about ethics, politics or morality in general.

Unforced variations: Feb 2019

Filed under: — group @ 1 February 2019

This month’s open thread for climate science discussions.

What the 2018 climate assessments say about the Gulf Stream System slowdown

Filed under: — stefan @ 28 January 2019

Last year, twenty thousand peer reviewed studies on ‘climate change’ were published. No single person can keep track of all those – you’d have to read 55 papers every single day. (And, by the way, that huge mass of publications is why climate deniers will always find something to cherry-pick that suits their agenda.) That is why climate assessments are so important, where a lot of scientists pool their expertise and discuss and assess and summarize the state of the art.

So let us have a quick look what last year’s climate assessments say about the much-discussed topic of whether the Atlantic Meridional Overturning Circulation (AMOC, a.k.a. Gulf Stream System) has already slowed down, as predicted by climate models in response to global warming.

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New Ocean Heat Content Histories

Guest commentary from Laure Zanna (U. Oxford) and G. Jake Gebbie (WHOI)

Two recent papers, Zanna et al. (2019) (hereafter ZKGIH19) and Gebbie & Huybers (2019) (hereafter GH19), independently reconstructed ocean heat content (OHC) changes prior to the instrumentally-based records (which start ~1950). The goals (and methodologies) of the two papers were quite different – ZKGIH19 investigated regional patterns of ocean warming and thermal sea level rise, while GH19 analyzed the long-term memory of the deep ocean – but they both touch on the same key questions of climate forcing and response.

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  1. L. Zanna, S. Khatiwala, J.M. Gregory, J. Ison, and P. Heimbach, "Global reconstruction of historical ocean heat storage and transport", Proceedings of the National Academy of Sciences, vol. 116, pp. 1126-1131, 2019.
  2. G. Gebbie, and P. Huybers, "The Little Ice Age and 20th-century deep Pacific cooling", Science, vol. 363, pp. 70-74, 2019.

The Climate Scientists are Alright

Filed under: — group @ 22 January 2019

Guest commentary from Eric Guilyardi (IPSL) and Valérie Masson-Delmotte (IPSL/IPCC)

[This is a translation of an article in Le Monde (Jan 11).]

In recent weeks in France, there has been a profusion of articles about the “climate scientist blues” (Le Monde 21/Dec, JDD 9/Dec, France Info 26/Sep), which has apparently affecting them “scientifically”. This follows a spate of similar articles in the US and Australian media (Esquire, 2015; The Monthly, 2018; Sierra Club Magazine, 2018). But what is the point of knowing the mood of scientists, or whether so-and-so is optimistic or pessimistic?

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Filed under: — gavin @ 21 January 2019

Given some unexpected down time this month (and maybe next month too!), I’ve been trying to go through key old posts on this site. The basic idea is to update links to other sites, references and figures that over the years have died (site domains that were abandoned, site redesigns, deliberate deletions etc.). Most notably, the IPCC website recently broke all the existing links to elements of the reports which we had referenced in hundreds of places. Thanks guys!

Some folk have been notifying us of issues they found (thanks Marcus!) and I’ve been fixing those as they come up, but obviously there are more. Links to old blog posts from Deltoid, Scienceblogs, Pielke Sr. or Prometheus generally don’t work anymore though they can sometimes be found on the wayback machine. It turns out a lot has changed since 2004 and many hotlinked images in particular have disappeared.

It’s obviously not worth finding replacements for every dead link, but digital uncluttering and fixing up is useful. So, please use this thread to notify us of any useful fixes we can make (and if you have an updated link,, that’d be perfect). Additionally, please let us know if any of the old content is still useful or interesting to you. We know there is still substantial traffic to the back catalog, so maybe it should be highlighted in some way?

To those of you who might ask whether blogging still brings me joy… of course it does!