Beer Can Survive a Nuclear Fallout

Originally posted here: https://mcgill.ca/oss/article/did-you-know/beer-can-survive-nuclear-fallout

In 1957 the U.S. government conducted a study aptly named “The Effect of Nuclear Explosions on Commercially Packaged Beverages”. The researchers placed cans and bottles of beer and other drinks in various proximities to a nuclear explosion, some above ground, some sheltered, and left them to experience the nightmare of a nuclear explosion.

Did the Fallout series get it right when they populated the post-apocalyptic wasteland with beer and cola bottles? Yes! Naturally, some beverages were hit by debris and broke, but any that remained physically intact werefound to be safe to drink. And drink them they did, declaring that the beverages closest to the blast tasted “definitely off”, but ones from a bit further away were still of “commercial quality”.

Could beer actually help us survive the apocalypse? There have been some claims that ethanol can act as a scavenger molecule, reacting with the dangerous free radicals produced by ionizing radiationand stopping their ill effects. That would help certainly explain all the drinking in Battlestar Galactica.

Sadly, while ethanol does show some scavenging activity, it’s fairly weak compared with some of the other bioactive scavengers we know about, like naringenin (found in grapefruits) and tocopherols (found in vegetable oils). Not to mention that the levels of radiation you’re likely to experience when traversing the wasteland of Canada are going to be a bit high for scavenging molecules to really help.

So, if the bombs do fall, remember that six-pack you have in the garage because, while it might not stop radiation, it might make the apocalypse a bit more bearable.  

What is Sea Foam and Why is it all Over the Beaches at Dunkirk?

Originally posted here: https://mcgill.ca/oss/article/you-asked/what-sea-foam-and-why-was-it-all-over-beaches-dunkirk

If you watched the summer blockbuster Dunkirk, you may have been left with the same question as one of our readers: what is sea foam and why was there so much of it at Dunkirk?

Well, the stuff that makes our beaches look like lattes turns out to be mostly gunk. It’s a collection of organic material, like algae, fish scales or bits of coral, that when agitated by the ocean’s waves and currents act as foaming agents and surfactants.

Surfactants are substances that lower the surface tension of water, basically reducing the attraction between water molecules allowing the surface to stretch around air bubbles. A foamis just a dispersion of a gas, in this case, air. in a liquid. When it comes to sea foam, more organic material means more surfactants, more foaming agents, and more foam, so when algae blooms or large fish schools die, you are likely to see more foam forming.

In 2007 a few giant storms off the coast of Sydney caused a massive influx of sea foam, causing the locals to refer to the beach as the Cappuccino Coast! While we likely won’t ever know exactly what caused the influx of foam during Dunkirk, my guess would be wastesfrom armies being dumped into waterways.

Surfactants don’t only cause bubbly beaches, though; they’re actually responsible for keeping us alive! Pulmonary surfactants in our lungs work to stabilize alveoli: small air-filled membrane bubbles that allow us to diffuse oxygen in, and waste gasses out of our lungs, just as they stabilize air bubbles in the sea.

Turtles Breathe Out of Their Butt

Originally published here: https://mcgill.ca/oss/article/did-you-know/turtles-breathe-out-their-butt

Technically the term is cloacal respiration, and it’s not so much breathing as just diffusing oxygen in and carbon dioxide out, but the fact remains: when turtles hibernate, their main source of oxygen is through their butt.

As cold-blooded animals, when the temperature drops in the winter, a turtle’s internal temperature drops with it, and its metabolism slows down to match. While they are in this slowed-metabolism hibernation period, their oxygen needs are quite low, and the oxygen diffused from the water running over them is enough to sustain them until spring. If times get really tough, they can always switch to anaerobic respiration: powering their metabolism without oxygen, but this mode comes with a time limit due to the buildup of a respiratory byproduct, lactic acid.

This breathing process is fairly common amongst amphibians and reptiles and is properly called cutaneous respiration. Besides the turtle butt-breathers, notable users of cutaneous respiration include frogs, salamanders and sea snakes. 

Why is the Sky Blue, or Better Yet, Why is the Ocean Blue?

Photo by Matteo Zamaria
Originally published here: https://mcgill.ca/oss/article/did-you-know/why-sky-blue-or-better-yet-why-ocean-blue

The sky is blue due to a phenomenon called Raleigh scattering. This scattering refers to the scattering of electromagnetic radiation (of which light is a form) by particles of a much smaller wavelength than it. Sunlight is scattered by the particles of the atmosphere, and what comes through down to earth is called diffuse sky radiation, and though only about 1/3rd of light is scattered, the smallest wavelengths of light tend to scatter easier. These shorter wavelengths correspond to blue hues, hence why when we look at the sky, we see it as blue. At sunset and sunrise, the angle at which sunlight enters the atmosphere is significantly changed, and most of the blue and green (shorter) wavelengths of light are scattered even before reaching the lower atmosphere, so we see more of the orange and red colours in the sky.

The ocean is not blue because it reflects the sky, though I believed that up until a few years ago. Water actually appears blue due to its absorption of red light. When light hits water, the water’s molecules absorb some of the photons from the light. Everything absorbs at a different wavelength (Your green t-shirt absorbs red), and as a result reflects the remaining colours back at a viewer (that’s why your t-shirt looks green). In shallow bodies of water (like a drinking glass) light penetrates it completely, as there is not enough water to absorb enough photons, so we see the water as colourless. In deeper waters however, not all the wavelengths of light can fully penetrate the liquid, as there are too many water molecules in the way of the photons. The water molecules absorb all the red wavelengths from the light, making it reflect blue. This is also why shallower waters appear ‘less’ or lighter blue than deeper ones- less absorption means less reflection.