Geek stuff – Page 81 – a sibilant intake of breath

Octopodes and tool use

Previously, I thought the most amusing use for empty coconut halves was emulating Monty Python and pretending that you are riding a horse. Now, it seems Indonesia’s Veined Octopus carries them around to use as an ad-hoc shelter. Apparently, this is the first unambiguous demonstration of tool use by an invertebrate. The behaviour is written up in the December 15th issue of Current Biology: “Defensive tool use in a coconut-carrying octopus:”

The fact that the shell is carried for future use rather than as part of a specific task differentiates this behaviour from other examples of object manipulation by octopuses, such as rocks being used to barricade lair entrances. Further evidence that this shell-carrying behaviour is an example of tool use comes from the requirement of the octopus to correctly assemble the separate parts (when transporting two shells) in order to create a single functioning tool.

Other significant talents of octopodes include colour shifting, escaping transparent boxes through tiny openings, using jellyfish tentacles as weapons, and having retinas the right way around, such that they have no blind spots.

Octopus intelligence has long been appreciated. For instance, Octopus vulgaris is the only invertebrate protected by the 1986 Animals (Scientific Procedures) Act (ASPA) in the UK.

Soft light layer in Photoshop

Here’s a nice little trick I learned to improve the contrast and saturation of images in Photoshop, without having to spend too much time messing around with levels or curves:

Open the original image
Create a duplicate layer (hit command-J on a Mac)
Right click on the new layer, in the layers tab
Select ‘blending options’
Under ‘blend mode’ choose ‘soft light’

The effect can be weakened or strengthened by adjusting the opacity of the layer. If you want to push it beyond 100%, just make another copy of the original layer and blend it in as above.

With portraits, this trick can make people look a bit red. If so, adjust the hue and saturation by selecting Adjustments >> Hue/Saturation. Then, edit ‘Reds’ by dragging the slider over a bit to include oranges, then reduce the level of saturation.

A video explanation of all this is online.

What’s the Worst That Could Happen?

Written by a high school science teacher, Greg Craven’s What’s the Worst That Could Happen? A Rational Response to the Climate Change Debate is a worthwhile and unusual addition to the catalogue of books on climate change. Craven’s chosen task is not to determine whether climate scientists are right in their projections of what human activity is and will do to the climate; rather, he is trying to prepare readers to make the best choice, given the uncertainty that will always exist.

This is the same basic message he popularized in a series of viral videos, the first and last of which are especially worth watching:

I do have one slight quibble with both. Craven’s decision grid suggests that we will eventually be able to look back and know if we made the right choice. I don’t think that’s true. If we take aggressive action and stop climate change, we may never know with certainty just how bad it would have been if we had ignored it. No matter how sophisticated they become, simulations can never give us total certainty, and we don’t have another planet with which to run an experiment. Similarly, if we take no action and climate change proves catastrophic, we will never know for sure what level of action would have been sufficient to stop it – or whether doing so was still possible at any particular point in time.

Craven’s approach is based around heuristics: examining the ways in which people make decisions, taking into consideration pitfalls like confirmation bias, and then developing an approach to make an intelligent choice. In this case, it involves developing a way to roughly rank the credibility of sources, look at who is saying what, and complete a decision grid that shows the consequences of climate change either being or not being a major problem and humanity either taking or not taking major action. His own conclusion is that taking action unnecessarily isn’t likely to be exceptionally economically damaging, and can be considered a prudent course for ensuring that the worst does not happen.

On the question of why action has not yet been taken, Craven focuses primarily on human psychology. We respond to threats that are immediate, visible, and have a hostile agent behind them. Since climate change is none of these things, it doesn’t trigger strong responses in us. Cognitive factors also help explain why people are so confused about the state of climate science, though individual failings in information assessment are accompanied by the failure of the media to pass along good information effectively.

Craven concludes that raising political will is the key action that needs to be taken, and that cutting individual emissions is of very secondary importance. Like many others, he draws on the analogy of WWII to show what the United States is capable of achieving when it has the determination.

Some readers may find the book’s informal style and fill-in-the-blanks exercises a bit annoying, or feel that they trivialize the issues at hand. That being said, Craven has produced a very accessible book that recasts the climate change debate in a valuable new way: evaluating what choice to make, under uncertainty, rather than trying to determine authoritatively who is right. For those wishing to grapple with the practical question of what ought to be done about climate change, this book is well worth reading.

Black carbon and climate change

[Image removed at the request of a subject (2019-10-01)]

Al Gore’s latest book – Our Choice: A Plan to Solve the Climate Crisis – includes a fair bit of discussion of black carbon, a human pollutant that causes global warming, but not in the same way carbon dioxide (CO2) does. Greenhouse gasses like CO2 prevent long-wave infrared radiation from leaving the Earth into space. Black carbon, by contrast, warms the planet by absorbing a lot of short-wave radiation from the sun. In essence, it has a very low albedo.

Some other pertinent things to know about black carbon:

The largest source is biomass combustion – such as burning forests and grasslands to clear them for agriculture.
The areas where this is happening most are Brazil, Indonesia, and Central Africa.
Black carbon settling in the Arctic is a major cause of warming there: possibly responsible for 1°C of the 2.5°C of warming already observed there.
Black carbon is also a major threat to Himalayan glaciers, which in turn provide the source water for rivers of critical human importance, such as the Ganges.
Black carbon is washed out of the atmosphere by rain, and only has a lifetime of a few weeks. If we stopped emitting it, its contribution to climate change would cease quickly.

The last of those is very encouraging. Unlike CO2, which remains in the atmosphere for a very long span of time, black carbon is something we could tackle on a short timescale, by mandating things like filters on diesel engines and the cleaner burning of coal and biomass.

As mentioned before, recent research has also highlighted the importance of non-CO2 greenhouse gasses. Anything that allows us to take more rapid and effective action to halt climate change is welcome news. Also, it requires a lot less political will to install better filters on diesel engines than it does to curb activities that are critically linked to greenhouse gas emissions.

Climate Change Futures Markets

Over at FiveThirtyEight – a website that leapt to fame on the basis of statistical analysis of the 2008 US election – there is a discussion of futures markets for climate change. The idea is to let people place bets on what will happen, and the hope is that the sum of opinions backed up with money will provide reasonably high quality information on what is likely and what is not:

Personally, I’d envision a robust series of contracts on temperature, CO2 emissions, precipitation, and perhaps tropical storms that expired at various intervals along the lines of those used for US Treasury bonds — say at 3, 5, 7, 10, 20, and 30 years. I’d encourage the use of options and perhaps derivatives, which can be helpful in pricing not just the mean estimates of temperature or precipitation but also the uncertainty surrounding these estimates. I’d run the markets through a major, cross-national platform such as the United Nations, IMF or World Bank, so as to encourage participation and create liquidity. And I’d make them open to as many people as possible with few legal restrictions or transaction costs.

This is similar to the idea of using such markets to predict the outcome of elections. While implementing the idea is bound to produce some problems, it could be a good thing to try. For one thing, it could help create mechanisms through which additional insurance could be provided for climatic risks, whether of extreme weather, crop failure, or other phenomena.

The Climatic Research Unit’s leaked emails

160 megabytes worth of emails – ostensibly from the University of East Anglia’s Climatic Research Unit – have apparently been obtained by hackers and posted online. Being emails between colleagues, they are written in a less formal style than public documents. Some blogs and news sources critical of the mainstream scientific view are hailing the emails as proof of poor practice within the scientific community, or evidence that the consensus view on climate change is incorrect or an intentional fabrication. Various climate change blogs have put up responses to the whole event and to those allegations:

Grist: Skeptics claim global warming is fake after top scientists’ emails hacked at CRU
RealClimate: The CRU hack
Greenfyre’s: CRU Hack, time to hit back … hard
DeSmogBlog: Climate contrarians spinning hard with stolen email files

Firstly, it isn’t clear that these emails contain evidence of any wrongdoing. Secondly, it hasn’t been established whether the documents are all genuine and unaltered. Thirdly, and most importantly, the consensus on anthropogenic climate change is bigger than any one specific institution. It is based on multiple lines of evidence that support the same conclusions – something that cannot be said about alternative hypotheses, such as that nothing is happening or that observed warming is not mostly being caused by greenhouse gasses.

RealClimate probably has the best analysis on the significance of all this:

More interesting is what is not contained in the emails. There is no evidence of any worldwide conspiracy, no mention of George Soros nefariously funding climate research, no grand plan to ‘get rid of the MWP’, no admission that global warming is a hoax, no evidence of the falsifying of data, and no ‘marching orders’ from our socialist/communist/vegetarian overlords. The truly paranoid will put this down to the hackers also being in on the plot though.

Instead, there is a peek into how scientists actually interact and the conflicts show that the community is a far cry from the monolith that is sometimes imagined. People working constructively to improve joint publications; scientists who are friendly and agree on many of the big picture issues, disagreeing at times about details and engaging in ‘robust’ discussions; Scientists expressing frustration at the misrepresentation of their work in politicized arenas and complaining when media reports get it wrong; Scientists resenting the time they have to take out of their research to deal with over-hyped nonsense. None of this should be shocking.

It’s obvious that the noise-generating components of the blogosphere will generate a lot of noise about this. but it’s important to remember that science doesn’t work because people are polite at all times. Gravity isn’t a useful theory because Newton was a nice person. QED isn’t powerful because Feynman was respectful of other people around him. Science works because different groups go about trying to find the best approximations of the truth, and are generally very competitive about that. That the same scientists can still all agree on the wording of an IPCC chapter for instance is thus even more remarkable.

That said, you can be sure that climate change delayers and deniers will be milking these emails for years – using them to continue to cast doubt on the strength of the scientific consensus about climate change. Thankfully, it does seem as though the world’s political elites are increasingly aware of the strength of the scientific consensus and the incoherence of the views of those who deny it.

[Update: 3 December 2009] Nature has posted an editorial about this whole incident. It makes reference to two open archives of online climate data – maintained by the IPCC (http://www.ipcc-data.org) and the US National Climatic Data Center (http://www.ncdc.noaa.gov/oa/ncdc.html).

[Update: 14 December 2009] Newsweek has printed a comprehensive evaluation of the significance of the CRU emails, written by Jess Henig of FactCheck.org. It concludes that the emails sometimes “show a few scientists in a bad light, being rude or dismissive” but that the emails do not undermine the IPCC consensus, and that: “E-mails being cited as “smoking guns” have been misrepresented.”

[Update: 20 June 2010] Wrap-up video on the CRU emails

Email and two-monitor setups

One thing I have discovered at work is how pleasant it is to have a monitor devoted exclusively to email. For me, email has become the central clearinghouse for virtually all information and action items. To remind myself of something, I send an email from my phone. I also track emails by applying ‘@Pending’ and ‘@Waiting For’ labels to them. Email can also be searched instantly, unlike having to search separately through blog posts, comments, wiki entries, document files, etc.

Having a second monitor exclusively for email is qualitatively different from having a window open, or even having a second desktop devoted to email use. This is because it is glanceable – you can check almost instantly and with minimal distraction whether anything new has come up. It is also easy to shift information from one screen to another: making reference to a document or website in a message, or adding information from an email to a website, calendar, etc. With a dedicated monitor, email never gets buried or left unnoticed for too long.

Much as I appreciate the 24″ screen on my iMac, I suspect I will eventually go for a two-monitor setup at home. Arguably, such a setup is a mark of excess. That being said, when your entire life is coordinated through computers, it is perhaps an acceptable area in which to devote resources (including a share of your direct and embedded greenhouse gas emissions).

Casting doubt on fusion power

Looking at a diagram of a proposed fusion reactor, it is easy to get the false sense that such technologies will provide clean and inexpensive power within a few decades: fusing tritium and deuterium to produce heat, while generating new fuel from lithium using the neutrons produced.

A post on The Oil Drum enumerates the many technical challenges associated with achieving that aim, going so far as to say that dreams about fusion power should be ‘ended’ as a consequence. Written by Dr. Michael Dittmar, a researcher with the Institute of Particle Physics of ETH Zurich, the article enumerates a number of significant problems:

Large amounts of tritium are required and various problems exist with it as a material and a fuel.
Materials from which reactor walls can be made are unavailable, and far beyond anything that is available.
Many obstacles exist to breeding tritium from Lithium-6.
Similarly, obstacles exist to extracting tritium from the lithium blanket and delivering it in a pure form into the chamber where fusion is occurring.
Reactors may not be able to breed enough tritium to keep themselves going, much less provide excess tritium for new facilities.

While this may not be cause for declaring fusion a complete non-starter, it is at least a useful way to temper the assumption that fusion power will emerge any decade now, providing a pain-free solution to the problems of climate change and fossil fuel depletion.

The article also lists problems with fission reactors that breed plutonium or use thorium as fuel: both options mooted in response to concerns about limited availability of uranium for use in conventional reactors. All this is a reminder that – while renewables may be costly and have intermittency problems to manage – there is every reason to believe they can be practically deployed starting immediately.

Anthropogenic climate change: evidence from isotopic ratios

Back in 2003, Prosenjit Ghosh and Willi Brand described one of the more clever ways in which the link between fossil fuel combustion and the accumulation of carbon dioxide in the atmosphere has been demonstrated. In their article “Stable isotope ratio mass spectrometry in global climate change research” (PDF), they discuss how the ratio of isotopes of carbon in the atmosphere can be used to identify the sources of atmospheric CO2. Their work was published in 2003, in the International Journal of Mass Spectrometry.

By tracking the ratio of carbon-12 to carbon-13 in the atmosphere, the distinctive imprint of fossil fuel combustion can be identified. This is really just confirmation of the inevitable chemical fact that burning coal, oil, and natural gas produces CO2. Nevertheless, it is nice to have an independent line of evidence showing that human activities really are the major cause behind observed increases in the atmospheric concentration of CO2.

The boundaries of reasonable climate change debate

In his well-argued book Why We Disagree About Climate Change, Mike Hulme does a good job of establishing the boundaries of the legitimate debate about climate change and what we ought to do about it:

Many of the disagreements that we observe are not really disputes about the evidence upon which our scientific knowledge of climate change is founded. We don’t disagree about the physical theory of absorption of greenhouse gases demonstrated by John Tyndall, about the thermometer readings first collected from around the world by Guy Callendar, or about the possibility of non-linear instabilities in the oceans articulated by Wally Broecker. We disagree about science because we have different understandings of the relationship of scientific evidence to other things: to what we may regard as ultimate ‘truth,’ to the ways in which we relate uncertainty to risk, and to what people believe to be the legitimate role of knowledge in policy making.

That’s as good a concise summary as I’ve seen. If the people you are debating accept that temperatures are rising, that greenhouse gasses cause warming, and the the climate system may react to human emissions in deeply disagreeable ways, you are within the realm where reasonable discussions can occur. By contrast, if your partners in discussion assert that climate is not changing, greenhouse gasses have nothing to do with it, and that any change will surely be benevolent and gradual… well… here be dragons.