Wednesday, 22 June 2016

Getting Biblical on CO2: How to turn your enemies to stone

Wouldn’t it be nice to have the power to turn your enemies into stone? It sounds like something out of the Old Testament or Greek myth, but it’s pretty darn effective. Unless they are careening down a hillside, at whose base you happen to be sitting, stones are relatively inert and harmless. Sadly, despite what religious texts or Tolkien books tell us, this probably isn’t a realistic strategy in the face of conflict.
Happily, no one told that to a group of scientists working in Iceland, who last week published the results of their 4-year research on turning one of humanities greatest foes into a ready supply of paperweights.

You’d be hard pressed to find a more fitting place for an epic showdown than Iceland. Desolate volcanic landscapes mix with moody weather to make it seem like the end of the world is always close at hand. Unfortunately, the gravitas of the setting is somewhat undone by the enemy we are talking about: a colourless, odorless, tasteless gas that every animal of Earth exhales but humans have found a special proclivity for pumping into the air. You know it as carbon dioxide (CO2).

Oddly enough, Iceland is one of the last places you would expect to find people working on a solution to carbon emissions. This isolated outpost of humanity in the North Atlantic gets virtually all of its power from geothermal sources. That is, the island is one big volcano, and so, they use its heat to keep the lights burning. This approach eliminates something like 95% of CO2 emissions associated with electricity production, but apparently that isn’t good enough for Icelandic scientists.

Wanting to inch a little closer to that zero-carbon goal, researchers at Hellisheidi power plant, near Reykjavik, decided to take some of their geothermal power plant’s paltry CO2 emissions and test an approach to neutralizing them; many people thought that was ridiculously impractical - ”that” being to pump the CO2 emissions deep into the ground and wait for them to turn to stone.

As you can imagine, this is a desirable way to fight climate change. The biggest challenge with carbon emissions is that gases are masterful escape artists. Put them into any container with even the slightest breach and they will soon be out mixing in the atmosphere like debutants at a cocktail party. Stone, by contrast, just tends to sit there and not do anything, like an awkward college freshman at their first frat party.

The science behind this idea is actually fairly straightforward. We have long known that when a type of rock called basalt is exposed to CO2 and a little water, the carbon will precipitate (solidify). The problem, like all things in geology, is a matter of time. In the type of uncontrolled field setting the Icelandic team was dealing with, ambitious estimates assume you would need eight years before a significant amount of the carbon was locked up.

So imagine the surprise (and presumed embarrassment) on the face of naysayers when the team from Hellisheidi reported that the process began in just a few months and that, after 2 years, 95 to 98% of the carbon injected into the rocks has turned into chalky, lifeless carbonate minerals. The process so far has been relatively small scale, pumping about 5,000 tonnes of CO2 underground per year – equal to about 15 Americans annual CO2 emissions – but it is promising.

For one thing, basalt as a resource isn’t exactly rare. Places like the Pacific Northwest, South America, and other volcanically endowed landscapes are ripe with it. Better yet, most of the Earth’s crust, beneath the oceans, is basalt. The only thing safer than turning your enemy to stone, is then placing that stone a mile or so underwater.

The major challenge at this point is cost, which sits around $17 per tonne of CO2. This compares favourably with other methods of capturing carbon emissions (usually between $23 and $95 per tonne), but is still expensive when you want to deploy it on the roughly 40 billion tonnes of CO2 that humans put into the air every year.

Clearly, we have some work to do to figure out how to scale up this technology, and in the mean time, we all need to take a hint from Iceland and switch our energy systems to renewable sources like wind, solar, and geothermal power. But, even once we stop treating the atmosphere like a garbage dump, we’re going to need technology to clean up the mess we’ve already made. The Hellisheidi technology gets us one step closer.

Wednesday, 15 June 2016

Blinded by the Sea: How eye glasses (and eyes) work

The ability to see is something we often take for granted. Every day, those of us with sight experience a range of shapes, sizes, colours, and movements that we only really appreciate when we are asked to – when watching Olympic gymnasts or when we’re confronted by something atypical, like a sunset or a mountain range. Most of us only really begin to appreciate the little things our eyes take in when they can no longer do so in a seamless way. For the average person, this happens as we age and our eyes naturally lose their ability to focus. For the not-so-average person, it can happen very suddenly.

Such an ‘unaverage’ (not a real word) experience befell our illustrator, here at Sketchy Science, just last week. While on a trip to a conference on the southeast coast of the United States, after a night of partaking in the local libations, our sketchist (also not a real word) found himself standing in the Atlantic ocean, when a rogue wave of epic (likely very small) proportions tossed him asunder, claiming his glasses to the surf. I don’t actually know if this is how it happened, but it is how I prefer to imagine it. It is much funnier than him simply dropping his glasses in the water.

Regardless of how it happened, the result was a fumbling Mr. Magoo-esque adventure through the airport, onto a plane, and back home to Canada. It’s amazing how two pieces of glass (or plastic) can play such a major role in a person’s life.

But how do glasses work and why do some of us need them? The answer lies in the three most common problems with respect to how our eyeballs function. The four parts of your eye that impact your ability to see are, from front to back - the cornea, which is the clear window on the front of your eye that lets light in; the pupil (the black part), which widens or narrows to let in more or less light; the lens, which bends and focuses the light; and the retina, which is the back wall of your eyeball onto which images are focused before sending impulses down the optic nerve into your brain for processing.

Most problems occur at the beginning of this whole operation, with the cornea. The tricky thing about eyeballs is that they are spheres, meaning that as light moves through their rounded surfaces, it bends. If your eye is not shaped just right, the light coming in can focus at a point that isn’t exactly on your retina.

If your cornea is exceptionally curvy, the light will bend too much and focus in front of the retina, leading to nearsightedness and trouble seeing distance objects; this is called Myopia.

If your cornea isn’t curvy enough, you have the opposite problem with light focusing behind the retina leading to farsightedness and trouble reading the newspaper; this is called Hyperopia.

If your cornea has a bump, ripple, or scratch on it, the light gets distorted in other ways, and this is called Astigmatism.

Glasses – or “corrective lenses”, if we want to be more accurate and inclusive of people with contact lenses – can correct these problems by bending the light in a way that compensates for misshapen corneas. The physics of light dictates that as light moves through a medium, such as glass, it bends or “refracts” towards the thickest part of that medium. Lenses are described as either “plus” or “minus” lenses depending on whether they are thicker in the middle or towards the edges.

Plus lenses are thick in the middle and so bend light inwards, leading to a focal point behind the lens itself. Pushing the focal point backward corrects for Myopia. Minus lenses refract light towards their edges, leading to a focal point that is actually in front of the lens itself. Moving the focus forward corrects for Hyperopia. To make things even more fun, plus and minus lenses can be combined to correct for more complicated vision problems.

That is really all there is to it. This impressive but simple technology has allowed people to see more clearly since the first pair of spectacles adorned some nobleman’s nose between 1268 and 1289 in Italy, after being invented by someone whose name has been lost to history. So, the person who thought up the way we still correct vision today will forever go as unappreciated as the clear vision he sought to bestow upon the masses, to only be admired when a rogue wave leaves one of us blinded.

Wednesday, 8 June 2016

Does your Dog Like Hugs? Truly Sketchy Science and the Value of Critical Thinking

As we all learned a few weeks ago, courtesy of John Oliver, sometimes the media misrepresents scientific findings. Things get blown out of proportion and the result can be total confidence in ideas that are totally wrong or frustration leading to mistrust of science in general. Fortunately, humans are equipped with an ability that few other animals demonstrate that allows us to sift through the nonsense. In school you may have learned about it as “critical thinking”, but in practice it is more like a bullshit-o-meter.

The ability to stop and ask ourselves “Wait, does that result actually make sense?” is incredibly powerful. It actually lies at the heart of science itself through the concept of peer-review, whereby other researchers get the opportunity to tear a study apart before it ever sees the light of day. Occasionally though, something slips through the cracks and it is up to the eye of the reader to spot something fishy. Such a case popped up on social media feeds around the world a last month with a study claiming, intentionally evocatively, that dogs don’t like hugs.

As a dog owner, I have my own biases that would lead me to question this research in the first place. I’ve hugged every dog I’ve ever owned and feel like my best friends would have hugged back had they possessed the appropriate shoulder joints and bipedal orientation to do so. But, that alone isn’t enough to discount the conclusions. Part of critical thinking is having an open mind and accepting the idea that I may have been wrong all these years… but I am within my rights to doubt it. That is where the critical part comes in.

The first fact worth pointing out is that, despite what the various click-bait style articles claimed, the research findings were not reported in a respected, peer-reviewed science journal. They were part of a blog post by UBC psychologist Stanley Coren, who was reporting on some data he collected from looking at pictures on the internet. The idea for the research came from Dr. Coren bringing his dog to school one day as part of a “Doggy De-stress Day” for overworked undergrads. The well-meaning doctor observed that his dog was not enjoying the hugs it was receiving and felt like he was on to something.

Now, looking at the anecdote and the research objectively, there are a couple of red flags right off the bat. A major one is that “Doggy De-Stress Day” would be better named “Doggy Distress Day” as any animal – dog, human, turtle, gibbon – that suddenly finds itself being attacked by strangers who seem hell-bent on using their arms as restraints is likely to get a little freaked out. As for the data that Dr. Coren collected by analyzing internet photos of dogs being hugged (he found that a whopping 81.6% of the dogs in the photos showed signs of stress), it also presents a couple of problems. Chief among them is that the researcher has no knowledge or control over the context in which the photos were taken. Are these purely candid moments or are the dogs being forced to pose for an overly excited person pointing a weird, flashing plastic thing (camera) at them?

A good way to evaluate the scientific merit of a conclusion is to think about how you would go about researching it under ideal conditions. If we want to test the hypothesis that dogs don’t like hugs, there are simple ways to get closer to an answer than by looking at random pictures online. First, you would want the dogs in an environment that doesn’t stress them out, preferably at home. That would allow us to rule out the surroundings as a source of stress and focus purely on the hugs. Second, you would want to control for the person doing the hugging. In this case, the findings are seeking to scold dog owners for forcing human affection onto dogs, so the dogs should only be hugged by people they know and trust. Finally, we would control the situation. Are the hugs happening out of the blue or is the dog relaxing with its owner on the couch after a long day of hiking? These are things that matter.

The point I’m trying to make is one that compliments John Oliver’s message about media misleading people about science: sometimes the research itself deserves to be questioned. You don’t need to misrepresent flawed research to reach the wrong conclusion; the data will take you there on its own. All the more reason to go back to the primary source of a new and shocking idea and ask yourself a few basic questions about how the findings were reached – well-meaning or not.

Until someone conducts a more controlled study, hug your dog. It makes you feel good and that’s all your dog wants for you anyway.