RealClimate

Climate science from climate scientists...

You are here: Home / Archives for Gavin

about Gavin Schmidt

Gavin Schmidt is a climate modeler, working for NASA and with Columbia University.

Marvel et al (2015) Part III: Response to Nic Lewis

by

The first post in this series gave the basic summary of Marvel et al (2015) (henceforth MEA15) and why I think it is an important paper. The second discussed some of the risible immediate media coverage. But there has also been an ‘appraisal’ of the paper by Nic Lewis that has appeared in no fewer than three other climate blogs (you can guess which). This is a response to the more interesting of his points.

[Read more…] about Marvel et al (2015) Part III: Response to Nic Lewis

References

  1. K. Marvel, G.A. Schmidt, R.L. Miller, and L.S. Nazarenko, "Implications for climate sensitivity from the response to individual forcings", Nature Climate Change, vol. 6, pp. 386-389, 2015. http://dx.doi.org/10.1038/nclimate2888

Marvel et al (2015) Part 2: Media responses

by

This is a second post related to the new Marvel et al (2015) paper. The first post dealing with the substantive content is here.

What with #AGU15 going on, and a little bit of overlap in content with Shindell (2014), NASA wasn’t particularly keen to put out a press release for the paper, but we did get a ‘web special‘ put out on Friday Dec 18th, the last day of AGU and a few days after the paper appeared online. I’ve been involved with many similar releases for papers and it is always a struggle to concisely say why a paper is interesting while not overselling it or being too technical (which is why only a small fraction of papers get press releases at all).

As we’ve previously remarked about other people’s press releases (eg. Stainforth et al or Willerslev et al), properly calibrating the aspect of a release that will get picked up by the media can be tricky, and so it proved in this case.

[Read more…] about Marvel et al (2015) Part 2: Media responses

References

  1. K. Marvel, G.A. Schmidt, R.L. Miller, and L.S. Nazarenko, "Implications for climate sensitivity from the response to individual forcings", Nature Climate Change, vol. 6, pp. 386-389, 2015. http://dx.doi.org/10.1038/nclimate2888

Marvel et al (2015) Part 1: Reconciling estimates of climate sensitivity

by

This post is related to the substantive results of the new Marvel et al (2015) study. There is a separate post on the media/blog response.

The recent paper by Kate Marvel and others (including me) in Nature Climate Change looks at the different forcings and their climate responses over the historical period in more detail than any previous modeling study. The point of the paper was to apply those results to improve calculations of climate sensitivity from the historical record and see if they can be reconciled with other estimates. But there are some broader issues as well – how scientific anomalies are dealt with and how simulation can be used to improve inferences about the real world. It also shines a spotlight on a particular feature of the IPCC process…

[Read more…] about Marvel et al (2015) Part 1: Reconciling estimates of climate sensitivity

References

  1. K. Marvel, G.A. Schmidt, R.L. Miller, and L.S. Nazarenko, "Implications for climate sensitivity from the response to individual forcings", Nature Climate Change, vol. 6, pp. 386-389, 2015. http://dx.doi.org/10.1038/nclimate2888

#AGU15

by

So this week it’s the biggest Earth Science meeting on the planet…



There is a lot of great science that will be freely streamed via AGU On-Demand (registration required), and there’ll be a lot of commentary using the hashtag #AGU15. Many posters will be available online too. A few highlights have already been discussed by Victor Venema related to the surface temperature station datasets, but there’ll be much more on offer if you dig deeper.

As the week goes on, we’ll link to anything good we see, and we’ll be happy to host any commentaries that anyone has on specific climate sessions or talks.

Happy conferencing!

NOAA temperature record updates and the ‘hiatus’

by

In a new paper in Science Express, Karl et al. describe the impacts of two significant updates to the NOAA NCEI (née NCDC) global temperature series. The two updates are: 1) the adoption of ERSST v4 for the ocean temperatures (incorporating a number of corrections for biases for different methods), and 2) the use of the larger International Surface Temperature Initiative (ISTI) weather station database, instead of GHCN. This kind of update happens all the time as datasets expand through data-recovery efforts and increasing digitization, and as biases in the raw measurements are better understood. However, this update is going to be bigger news than normal because of the claim that the ‘hiatus’ is no more. To understand why this is perhaps less dramatic than it might seem, it’s worth stepping back to see a little context…

[Read more…] about NOAA temperature record updates and the ‘hiatus’

References

  1. T.R. Karl, A. Arguez, B. Huang, J.H. Lawrimore, J.R. McMahon, M.J. Menne, T.C. Peterson, R.S. Vose, and H. Zhang, "Possible artifacts of data biases in the recent global surface warming hiatus", Science, vol. 348, pp. 1469-1472, 2015. http://dx.doi.org/10.1126/science.aaa5632
  2. B. Huang, V.F. Banzon, E. Freeman, J. Lawrimore, W. Liu, T.C. Peterson, T.M. Smith, P.W. Thorne, S.D. Woodruff, and H. Zhang, "Extended Reconstructed Sea Surface Temperature Version 4 (ERSST.v4). Part I: Upgrades and Intercomparisons", Journal of Climate, vol. 28, pp. 911-930, 2015. http://dx.doi.org/10.1175/JCLI-D-14-00006.1

Reflections on Ringberg

by

As previewed last weekend, I spent most of last week at a workshop on Climate Sensitivity hosted by the Max Planck Institute at Schloss Ringberg. It was undoubtedly one of the better workshops I’ve attended – it was focussed, deep and with much new information to digest (some feel for the discussion can be seen from the #ringberg15 tweets). I’ll give a brief overview of my impressions below.

[Read more…] about Reflections on Ringberg

Climate Sensitivity Week

by

Some of you will be aware that there is a workshop on Climate Sensitivity this week at Schloss Ringberg in southern Germany. The topics to be covered include how sensitivity is defined (and whether it is even meaningful (Spoiler, yes it is)), what it means, how it can be constrained, what the different flavours signify etc. There is an impressive list of attendees with a very diverse range of views on just about everything, and so I am looking forward to very stimulating discussions.

[Read more…] about Climate Sensitivity Week