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Climate change and consequences on the ground

Filed under: — rasmus @ 13 March 2013

The link between extreme weather events, climate change, and national security is discussed in Extreme Realities, a new episode in PBS’ series Journey To Planet Earth hosted by Matt Damon.

The video features a number of extreme weather phenomena: hurricanes, tornadoes, floods, wild fires, and flooding. The discussion is about climate change and the consequences on the ground – or, how climate change may affect you.

It is important to ask what is the story behind the assertions made in the video. What scientific support is there for the link between such extremes and climate change?

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Stronger regional differences due to large-scale atmospheric flow.

A new paper by Deser et al. (2012) (free access) is likely to have repercussions on discussions of local climate change adaptation. I think it caught some people by surprise, even if the results perhaps should not be so surprising. The range of possible local and regional climate outcomes may turn out to be larger than expected for regions such as North America and Europe.

Deser et al. imply that information about the future regional climate is more blurred than previously anticipated because of large-scale atmospheric flow responsible for variations in regional climates. They found that regional temperatures and precipitation for the next 50 years may be less predictable due to the chaotic nature of the large-scale atmospheric flow. This has implications for climate change downscaling and climate change adaptation, and suggests a need to anticipate a wider range of situations in climate risk analyses.

Although it has long been recognised that large-scale circulation regimes affect seasonal, inter-annual climate, and decadal variations, the expectations have been that anthropogenic climate changes will dominate on time scales longer than 50 years. For instance, an influential analysis by Hawking & Sutton (2009) (link to figures) has suggested that internal climate variability account for only about 20% of the variance over the British isles on a 50-year time scale.
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  1. C. Deser, R. Knutti, S. Solomon, and A.S. Phillips, "Communication of the role of natural variability in future North American climate", Nature Climate Change, vol. 2, pp. 775-779, 2012.
  2. E. Hawkins, and R. Sutton, "The Potential to Narrow Uncertainty in Regional Climate Predictions", Bull. Amer. Meteor. Soc., vol. 90, pp. 1095-1107, 2009.

Embargos and confidentiality

Filed under: — gavin @ 23 September 2012

This post is not about climate science, but rather about the science/media interface.

As many of you may be aware, papers that are scheduled to appear in high-profile journals (Science, Nature and a few others) are often released a few days early to journalists under embargo in order to give them a chance to do a fuller story and talk to more people about it prior to filing. On balance, this works reasonably well, and the press stories that come out are on the whole better for it (there is a bigger issue with the need for a news peg for most science stories that this practice dominates, but that isn’t the focus of this post).

But Carl Zimmer and Maggie Koerth-Baker recently reported on a situation where a high profile paper was only provided to journalists under embargo if they signed a non-disclosure agreement restricting their ability to show it to other scientists for comment.

This is both very unusual and, frankly, appalling. Science and science publishing are not a branch of the PR industry but part of an open and self-critical process of inquiry. Authors and scientists who do not want their results discussed and/or criticised should not submit them for publication in the first place. As Koerth-Baker and Zimmer make clear, articles about new papers that are simply reworded official statements are not journalism at all. Indeed, the need for journalists to get an unaffiliated opinion from the author’s peers is an essential check on the occasional tendency of press releases to go over the top when pushing a particular study, and is something that should be happening more, not less.

This post is really just about putting on record that this is not a practice that ‘scientists’ are advocating for and we, like the journalists linked above, would strongly advise that if such conditions are imposed, journalists, journals and editors do not accede to them. That will help resolve the issue of whether ‘no publicity’ is indeed preferable.

Finally, while I am sort of on the topic of science journalism, can’t we please, please, please mandate the citation of the DOI tag in any online story about a new paper? Tracking down the actual paper being described is all-too-often far more difficult than it needs to be. (For example, the doi for the study referred to above took four links and a targeted google search to find. Why?).

Science journalism is going through a tough time at the moment, and practices that take the reporting of science further away from science as a process and more towards the repetition of ‘gee whiz’ factoids, should be resisted by anyone who cares about the public’s engagement with science.


  1. G. Séralini, E. Clair, R. Mesnage, S. Gress, N. Defarge, M. Malatesta, D. Hennequin, and J.S. de Vendômois, "RETRACTED: Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize", Food and Chemical Toxicology, vol. 50, pp. 4221-4231, 2012.

Antarctic Peninsula warming: natural variability or “global warming”?

Filed under: — eric @ 23 August 2012

Most people know that the Antarctic Peninsula is one of the most rapidly warming places on earth. But like everywhere else in Antarctica, the length of available temperature data is short — most records begin in 1957 (when stations were put in place during the International Geophysical Year); a few start in the late 1940s. This makes the recent rapid warming difficult to evaluate; in general, what’s interesting is how the trend compares with the underlying variability. As anyone who’s been there can tell you, the weather on the Antarctic Peninsula is pretty wild, and this applies to the climate as well: year to year variability is very large. Put another way, the noise level is high, and discerning the signal requires more data than is available from the instrumental temperature record. This is where ice cores come in handy — they provide a much longer record, and allow us to evaluate the recent changes in a more complete context.

A new paper in Nature this week presents results from an ice core drilled by the British Antarctic Survey (BAS) at James Ross Island on the Antarctic Peninsula. More »

Let the games begin!

Filed under: — gavin @ 4 August 2012

I picked a good weekend to be out of cell phone range and unconnected to the internet – and judging from how the rest of the week has gone, I’d have been minded to stay there…

As most readers are probably aware, there was an op-ed in the Saturday New York Times from Richard Muller announcing the Berkeley Earth team’s latest results. It was odd enough that a scientific paper was announced via an op-ed, rather than a press release, odder still that the paper was only being submitted and had not actually been accepted, and most odd of all was the framing – a ‘converted skeptic’ being convinced by his studies that the planet has indeed warmed and that human activity is the cause – which as Mike and Ken Caldiera pointed out has been known for almost 2 decades.

Not wanting to be upstaged, plenty of ‘unconverted skeptics’ – including Anthony Watts and Ross McKitrick decided to stage dramatic press events and release barbs of their own. This was followed by a general piling on of commenters and bloggers trying to spin the events in their preferred direction combined with plenty of cluelessness in the general media about exactly who these people are (no-one special), what earth-shattering discovery had been made (none) and what it all means (not a lot).

The ‘best’ response to this circus is to sit back and see how pretzel-like the logical justifications can become. I particularly like the recent twist to the “No true scotsman” post-hoc rationalisation. Since the ‘converted skeptic’/prodigal scientist meme is a very powerful framing for the media, the obvious riposte for the ‘skeptics’ is to declare that Muller was not a true skeptic. But since these terms have become meaningless in terms of any specific position, this ends up as a semantic argument that convinces no-one but the faithful.

The actual trigger for all this hoopla is the deadline for papers that can be cited in the Second Order Draft of the new IPCC report. They needed to have been submitted to a journal by Tuesday (31 July) to qualify. Of course, they also need to be interesting, relevant and known to the IPCC lead authors. But there seems to be far too much emphasis being put on this deadline. The AR5 report is pretty much 90% written, and the broad outlines have been known for ages. Very few of the papers that have been submitted this week are anything other than minor steps forward and only a small number will be accorded anything other than a brief mention in AR5, and most not even that.

Furthermore, once the SOD is finalised (Aug 10), Tuesday’s deadline becomes moot, and the only thing that matters for the final report is whether papers are accepted by March 2013. (In a spirit of full disclosure, I should mention that I was working on a couple of papers with an eye to making this deadline, but in the end decided it was preferable to take the time to do a good job on the papers than to submit something shoddy).

The only worthwhile substance to any of this is the work that has mostly been done by Robert Rohde on the Berkeley Earth code and database as we’ve noted previously – and once this week’s drama has faded into the distance overshadowed by some new blog-storm, this work will still be a useful advance.

But still the games go on. Senate hearings are one of the longest running games of political theatre going – where the Senators pretend to listen to the panelists and the panelists pretend that this is an efficient way to inform policymakers. This week’s was little different from the ones in the past – some earnest submissions from the mainstream, and a cherry-pickers delight of misinformation from the Republican invitee, John Christy, who even quoted the woefully inept first draft of the Watts paper as if it meant something.

To confuse the metaphor even further, Roger Pielke Sr loudly declared that whatever the results of the Watts paper it will end up being a game changer:

The TOB effect could result in a confirmation of the Watts et al conclusion, or a confirmation (from a skeptical source) that siting quality does not matter. In either case, this is still a game changing study.

If only people would change the games they play…

My inclination is just to sit back and watch the spectacle, admire the logic-defying leaps, marvel at the super-human feats of hubris and, in two weeks time, remark on how little actually changed.

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