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Advocacy vs. Science

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The advocate will pick up any piece of apparently useful data and without doing any analysis, decide that their pet theory perfectly explains any anomaly without consideration of any alternative explanations. Their conclusion is always that their original theory is correct.

The scientist will look at all possibilities and revise their thinking based on a thorough assessment of all issues – data quality, model quality and appropriateness of the the comparison. Their conclusion follows from the analysis whatever it points to.

Which one is which?

Farewell to our Readers

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We would like to apologize to our loyal readers who have provided us so much support since we first went online in December 2004. However, after listening to the compelling arguments of the distinguished speakers who participated in the Heartland Institute’s recent global warming contrarian conference, we have decided that the science is settled — in favor of the contrarians. Indeed, even IPCC chair Rajendra Pachauri has now admitted that anthropogenic climate change was a massive hoax after all. Accordingly, RealClimate no longer has a reason for existence. The contrarians have made a convincing case that (a) global warming isn’t happening, (b) even if it is, its entirely natural and within the bounds of natural variability, (c) well, even if its not natural, it is modest in nature and not a threat, (d) even if anthropogenic warming should turn out to be pronounced as projected, it will sure be good for us, leading to abundant crops and a healthy environment, and (e) well, it might actually be really bad, but hey, its unstoppable anyway. (Can we get our check now?)

Michaels’ new graph

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Every so often people who are determined to prove a particular point will come up with a new way to demonstrate it. This new methodology can initially seem compelling, but if the conclusion is at odds with other more standard ways of looking at the same question, further investigation can often reveal some hidden dependencies or non-robustness. And so it is with the new graph being cited purporting to show that the models are an “abject” failure.

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With all due respect…

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Translations: (Italian) (English)

There was a great comedy piece a few years back (whose origin escapes us) that gave examples of how the English would use their language when speaking to a non-native speaker to imply the precise opposite of what was actually being understood. This allowed the English to feel superior without actually damaging international relations. One example was the phrase “with all due respect” which is generally understood to imply that the speaker has a great deal of respect for their counterpart, while the speaker is actually implying that they have no respect in the slightest for their interlocutor. The respect due being precisely zero.

This thought occurred to us when a few of us opened our email this week to see a draft ad being sent around by the Cato Institute (i.e. Pat Michaels) looking for signatories prior to being published in “major US newspapers” sometime soon:

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Olympian efforts to control pollution

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There is a new paper in Science this week on changes to atmospheric visibility. In clear sky conditions (no clouds), this is related mainly to the amount of aerosols (particulate matter) in the air (but is slightly dependent on the amount of water vapour as well, which is corrected for in this study). The authors report that the clear-sky visibility has decreased almost everywhere (particularly in Asia) from 1973 to 2007, with the exception of Europe where visibility has increased (consistent with the ‘brightening trend’ reported recently). Trends in North American stations seem relatively flat.

There is another story that didn’t get as much press when it came out late last year but that is highly relevant to this issue – whether any of the efforts that the Chinese authorities to reduce air pollution ahead of the Olympics last year had any impact. To the extent that they did, they might point the way to reducing aerosols and other pollutants across Asia, but it might also reveal how hard it is to do so.
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Advice for a young climate blogger

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Translations: (Italian) (Español) (English)

Congratulations! You have taken the first step towards attempting to communicate your expertise and thoughts to the wider world, which remains poorly served by its traditional sources of information when it comes to complex societally relevant issues like climate change. Your aim to clarify the science (or policy options or ethical considerations or simply to explain your views) is a noble endeavor and we wish you luck and wide readership. But do be aware that you are dipping your blog into sometimes treacherous waters. Bad things can happen to good bloggers. So in a spirit of blog-camaraderie, and in light of our own experiences and observations, we offer some advice that may be of some help in navigating the political climate relatively unscathed.

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What George Will should have written

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We’ve avoided piling on to the George Will kerfuffle, partly because this was not a new story for us (we’d commented on very similar distortions in previous columns in 2004 and 2007), but mostly because everyone else seems to be doing a great job in pointing out the problems in his recent columns.

We are actually quite gratified that a much wider group of people than normal have been involved in calling out this latest nonsense, taking the discussion well outside the sometimes-rarefied atmosphere of the scientific blogosphere (summary of links). Maybe RealClimate has succeeded in its original aim of increasing the wider awareness of the scientific context? However, like many, we are profoundly disappointed in the reaction of the Washington Post editors and George Will himself (though the ombudsman’s column today is a step in the right direction). It would have been pleasant to see an example of the conservative punditocracy actually learning something from the real world instead of resorting to ever-more unconvincing pseudo-legalistic justifications and attacks on the messenger to avoid taking their head out of the sand. Nonetheless, in a moment of naive optimism, we have allowed ourselves to indulge in a fantasy for how a more serious columnist might have dealt with the issue:
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It’s wrong to wish on space hardware

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A number of satellite related issues have come up this weekend: The NSIDC reminded us that satellite sensors are (like all kinds of data) not perfectly reliable and do not last forever. Two satellites collided by accident last week, littering the orbit with dangerous amounts of debris. In San Diego this weekend, I was fortunate enough to attend a meeting with some of the Apollo astronauts and some of the scientists involved in Cassini and the Mars Phoenix missions. And yesterday morning we heard that the Orbiting Carbon Observatory mission launch failed to insert the satellite into orbit, and it is presumably measuring carbon dioxide somewhere at the bottom of the Southern Ocean. Coincidentally, when it came up on the news, I was in a meeting with one of the scientists who had been working on setting up a climate model to assimilate the OCO data in order to pin down the carbon sinks.

All of these events have served to remind me at least, that although the space age is 50 years old, we are a long way from the point where we can take our ability to launch and control off-planet machines for granted. Getting into space was, and remains, a tremendous challenge. This makes the successes we’ve had all the more incredible, and a testament to the hard work the engineers and scientists do over many years before a launch to give the missions the best chance of success.
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Linking the climate-ecology attribution chain

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Guest commentary by Jim Bouldin, Department of Plant Sciences, UC Davis

Linking the regional climate-ecology attribution chain in the western United States

Many are obviously curious about whether certain current regional environmental changes are traceable to global climate change. There are a number of large-scale changes that clearly qualify—rapid warming of the arctic/sub-arctic regions for example, and earlier spring onset in the northern hemisphere and the associated phenological changes in plants and animals. But as one moves to smaller scales of space or time, global-to-local connections become more difficult to establish. This is due to the combined effect of the resolutions of climate models, the intrinsic variability of the system and the empirical climatic, environmental, or ecological data—the signal to noise ratio of possible causes and observed effects. Thus recent work by ecologists, climate scientists, and hydrologists in the western United States relating global climate change, regional climate change, and regional ecological change is of great significance. Together, their results show an increasing ability to link the chain at smaller and presumably more viscerally meaningful and politically tractable scales.
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Bushfires and extreme heat in south-east Australia

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Translations: (Deutsch) (Español) (Italian) (English)

Guest commentary by David Karoly, Professor of Meteorology at the University of Melbourne in Australia

On Saturday 7 February 2009, Australia experienced its worst natural disaster in more than 100 years, when catastrophic bushfires killed more than 200 people and destroyed more than 1800 homes in Victoria, Australia. These fires occurred on a day of unprecedented high temperatures in south-east Australia, part of a heat wave that started 10 days earlier, and a record dry spell.

This has been written from Melbourne, Australia, exactly one week after the fires, just enough time to pause and reflect on this tragedy and the extraordinary weather that led to it. First, I want to express my sincere sympathy to all who have lost family members or friends and all who have suffered through this disaster.

There has been very high global media coverage of this natural disaster and, of course, speculation on the possible role of climate change in these fires. So, did climate change cause these fires? The simple answer is “No!” Climate change did not start the fires. Unfortunately, it appears that one or more of the fires may have been lit by arsonists, others may have started by accident and some may have been started by fallen power lines, lightning or other natural causes.

Maybe there is a different way to phrase that question: In what way, if any, is climate change likely to have affected these bush fires?

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