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The Moscow Warming Hole

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This week, PNAS published our paper Increase of Extreme Events in a Warming World, which analyses how many new record events you expect to see in a time series with a trend. It does that with analytical solutions for linear trends and Monte Carlo simulations for nonlinear trends.

A key result is that the number of record-breaking events increases depending on the ratio of trend to variability. Large variability reduces the number of new records – which is why the satellite series of global mean temperature have fewer expected records than the surface data, despite showing practically the same global warming trend: they have more short-term variability.

Another application shown in our paper is to the series of July temperatures in Moscow. We conclude that the 2010 Moscow heat record is, with 80% probability, due to the long-term climatic warming trend. [Read more…] about The Moscow Warming Hole

Berkeley earthquake called off

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Anybody expecting earthshaking news from Berkeley, now that the Berkeley Earth Surface Temperature group being led by Richard Muller has released its results, had to be content with a barely perceptible quiver. As far as the basic science goes, the results could not have been less surprising if the press release had said “Man Finds Sun Rises At Dawn.” This must have been something of a disappointment for anyone hoping for something else.

[Read more…] about Berkeley earthquake called off

A Well Deserved Honor

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The rest of us here would like to congratulate Gavin on a well-deserved honor. He is the recipient of the inaugural AGU Climate Communication Prize. Since co-founding RealClimate back in 2004, Gavin has emerged as the de facto leader of RealClimate, having written the majority of our posts–and many of our best ones. One of his very first contributions “Michael Crichton’s State of Confusion” remains one of our most highly cited posts. One of his most recent, about what the recent CERN experiments do (and don’t) tell us about cloud processes, is a good example of his characteristic knack for explaining complex scientific issues with clarity and wit. Gavin also takes the lead role in dealing with the comments on RC posts. His almost non-stop, patient, response to the flood of comments that ensued in the week following the CRU email server hack in late 2009 impressed us all.

Gavin’s communication efforts, of course, go well beyond RealClimate. He is frequently quoted in mainstream news venues and often appears on radio and television news programs, to help communicate key aspects of climate science to the public. Here he is in an interview articulating both the science and the history of the science, and putting the recent politicizing of climate science into context. (It’s worth watching this interview to the end, by the way, for some thoughts on what you can do to improve communication of climate science.) He’s also produced a very accessible and beautiful book, Climate Change: Picturing the Science (with photographer Josh Wolfe).

Gavin’s efforts go well beyond the classic ‘public understanding of science’, since what he so successfully promotes is the ‘public understanding of research’. He makes it understandable and tangible how scientists work and think, not just what their results are. Gavin is a champion of easy access to data: see our Realclimate section on data sources. And, of course, a champion of making good use of the available data: see his many articles where he explains how particular questions (such as whether climate models agree with data) should not be speculated about but can be answered by anyone with basic skills simply by using publicly available data archives. Gavin’s work is often about empowering people to draw their own conclusions.

All of this is based on a solid foundation of his own scientific research: Gavin is a top-notch climatologist with an excellent publication record (h-index: 33), and we and our colleagues refer frequently to Gavin’s numerous papers in our own research and teaching. We only sometimes wonder whether his days have 30 hours, or how he finds the time to achieve all this.

Of course we’re a bit biased here at RealClimate, but it is truly hard to imagine a more deserving recipient for this award than Gavin.

Congratulations, once again, to our colleague and friend.

Mike Mann, Eric Steig, Stefan Rahmstorf, Jim Bouldin, Ray Pierrehumbert, David Archer, and the rest of RealClimate

The high cost of inaction

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In 2004 Stephen Pacala and Robert Socolow published a paper in Science in which they argued that a pragmatic, but still difficult, way of stabilizing atmospheric CO2 levels over the long term was via the implementation of seven “stabilization wedges” over the next 50 years. The idea was very simple: each wedge represented one in-hand technology or societal practice that could be implemented, relatively slowly at first and increasing linearly with time, to make a small but growing dent in the rise in CO2 emissions, stabilizing them at 2004 levels (about 7 Gigatons C/Year) over the next 50 years (see figure below).
[Read more…] about The high cost of inaction

Speculative polar cartography

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Guest commentary from Kevin Brown

The curious mismapping of Greenland’s ice sheet cover by the venerable Times Atlas recently has excited a lot of outraged commentary. But few people noted that this follows an old tradition of speculative cartography of the polar regions. ‘Modern’ mapmakers as early as the 16th century combined real facts and scientific knowledge with fundamental misinterpretations of that knowledge to create speculative mappings of the world’s unknown shores – and nowhere was this more prevalent than at the poles.

Early cartographers had a particularly difficult time mapping the Polar Regions. Factually, they based their maps on reports from mariners who dared sail the dangerous waters. This was supplemented by information from earlier maps, speculations based upon their personal theories of geography, religious beliefs, and the fiscal and political ambitions of their patrons.
[Read more…] about Speculative polar cartography

Global warming and ocean heat content

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The connection between global warming and the changes in ocean heat content has long been a subject of discussion in climate science. This was explicitly discussed in Hansen et al, 1997 where they predicted that over the last few decades of the 20th Century, there should have been a significant increase in ocean heat content (OHC). Note that at the time, there had not been any observational estimate of that change (the first was in 2000 (Levitus et al, 2000)), giving yet another example of a successful climate model prediction. At RC, we have tracked the issue multiple times e.g. 2005, 2008 and 2010. Over the last few months, though, there have been a number of new papers on this connection that provide some interesting perspective on the issue which will certainly continue as the CMIP5 models start to get analysed.
[Read more…] about Global warming and ocean heat content

References

  1. S. Levitus, J.I. Antonov, T.P. Boyer, and C. Stephens, "Warming of the World Ocean", Science, vol. 287, pp. 2225-2229, 2000. http://dx.doi.org/10.1126/science.287.5461.2225

Cosmic rays and clouds: Potential mechanisms

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Guest Commentary by Jeffrey Pierce (Dalhousie U.)

I’ve written this post to help readers understand potential physical mechanisms behind cosmic-ray/cloud connections. But first I briefly want to explain my motivation.

Prior to the publication of the aerosol nucleation results from the CLOUD experiment at CERN in Nature several weeks ago Kirkby et al, 2011, I was asked by Nature Geoscience to write a “News and Views” on the CLOUD results for a general science audience. As an aerosol scientist, I found the results showing the detailed measurements of the influences of ammonia, organics and ions from galactic cosmic rays on aerosol formation exciting. While none of the results were entirely unexpected, the paper still represents a major step forward in our understanding of particle formation. This excitement is what I tried to convey to the general scientific audience in the News and Views piece. However, I only used a small portion of the editorial to discuss the implications to cosmic rays and clouds because (1) I felt that these implications represented only a small portion of the CLOUD findings, and (2) the CLOUD results address only one of several necessary conditions for cosmic rays to affect clouds, and have not yet tested the others.

Many of the news articles and blog posts covering the CLOUD article understandably focused much more on the cosmic-ray/cloud connection as it is easy to tie this connection into the climate debate. While many of the articles did a good job at reporting the CLOUD results within the big picture of cosmic-ray/cloud connections, some articles erroneously claimed that the CLOUD results proved the physics behind a strong cosmic-ray/cloud/climate connection, and others still just got it very muddled. A person hoping to learn more about cosmic rays and clouds likely ended up confused after reading the range of articles published. This potential confusion (along with many great questions and comments in Gavin’s CLOUD post) motivated me to write a general overview of the potential physical mechanisms for cosmic rays affecting clouds. In this post, I will focus on what we know and don’t know regarding the two major proposed physical mechanisms connecting cosmic rays to clouds and climate.
[Read more…] about Cosmic rays and clouds: Potential mechanisms

References

  1. J. Kirkby, J. Curtius, J. Almeida, E. Dunne, J. Duplissy, S. Ehrhart, A. Franchin, S. Gagné, L. Ickes, A. Kürten, A. Kupc, A. Metzger, F. Riccobono, L. Rondo, S. Schobesberger, G. Tsagkogeorgas, D. Wimmer, A. Amorim, F. Bianchi, M. Breitenlechner, A. David, J. Dommen, A. Downard, M. Ehn, R.C. Flagan, S. Haider, A. Hansel, D. Hauser, W. Jud, H. Junninen, F. Kreissl, A. Kvashin, A. Laaksonen, K. Lehtipalo, J. Lima, E.R. Lovejoy, V. Makhmutov, S. Mathot, J. Mikkilä, P. Minginette, S. Mogo, T. Nieminen, A. Onnela, P. Pereira, T. Petäjä, R. Schnitzhofer, J.H. Seinfeld, M. Sipilä, Y. Stozhkov, F. Stratmann, A. Tomé, J. Vanhanen, Y. Viisanen, A. Vrtala, P.E. Wagner, H. Walther, E. Weingartner, H. Wex, P.M. Winkler, K.S. Carslaw, D.R. Worsnop, U. Baltensperger, and M. Kulmala, "Role of sulphuric acid, ammonia and galactic cosmic rays in atmospheric aerosol nucleation", Nature, vol. 476, pp. 429-433, 2011. http://dx.doi.org/10.1038/nature10343

Greenland meltdown

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After a record-breaking 2010 in terms of surface melt area in Greenland Tedesco et al, 2011, numbers from 2011 have been eagerly awaited. Marco Tedseco and his group have now just reported their results. This is unrelated to other Greenland meltdown this week that occurred at the launch of the new Times Atlas.
[Read more…] about Greenland meltdown

References

  1. M. Tedesco, X. Fettweis, M.R. van den Broeke, R.S.W. van de Wal, C.J.P.P. Smeets, W.J. van de Berg, M.C. Serreze, and J.E. Box, "The role of albedo and accumulation in the 2010 melting record in Greenland", Environmental Research Letters, vol. 6, pp. 014005, 2011. http://dx.doi.org/10.1088/1748-9326/6/1/014005

Hooked on ‘theWeather’

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During the annual European Meteorological Society’s (EMS) annual meeting in Berlin, I was pleasantly surprised by a magazine called ‘theWeather’, issued by the theWeather Club, an outreach activity associated with the Royal Meteorological Society. TheWeather Club was awarded the EMS outreach & Communication award 2011 for this magazine.

[Read more…] about Hooked on ‘theWeather’