The World is Your…Sewer??

My Lead Science Cutie on staff (who I pay with milkshakes and bizarre postcards) has given me an excellent topic. Recently I chose to donate to a group looking to limit/control the dumping of human waste into the ocean from cruise ships. Science Cutie naturally wondered how big an impact this could have on a body of water as large as the ocean. My answer was “very” and “because eutrophication”.

Eutrophication is enrichment of an aquatic environment with nutrients. It’s natural in lakes and ponds over time, I’m sure most people reading have been around some stinky, algae filled ponds in their time and will have seen what I mean (even if you didn’t all know it at the time). Besides clouding the water and filling pond and lake bottoms with sediment, thereby reducing clarity (and light available underwater), eutrophication allows algal blooms to flourish and grow. Without enough light, they’ll start consuming oxygen. During particularly intense eutrophication, this can essentially suffocate other species.

This can radically change a habitat, but natural eutrophication is VERY slow, and though the build-up of sediment and nutrients may result in the lake or pond disappearing completely, local species have been adapting along with the changing water body. I mean, the fish and stuff are toast, but the lake/pond would have been supporting less and less of those things for a WHILE. But then there’s Unnatural eutrophication…That is, human-induced eutrophication.

Now we get to the cruise ships…

Human-induced eutrophication is a result of organic pollution, as with agriculture runoff or the dumping of human waste from ships or poorly managed sewers. Dee-lightful. Besides the aforementioned depletion of oxygen and light availability, toxic algae and bacteria can effectively poison local species. In the ocean, we are most familiar with this process as Red Tide. Toxins build up in the food chain as predators eat many things with a little toxin, then something bigger eats many of those and so on. This also impacts us because, considering we have found a away to eat almost everything in the sea, our big tasty fish dinner may have consumed enough toxic smaller fish to make it toxic to US. Yay. So now we have Red Tide warnings to let us know when and where we’ve totally messed everything up. If that’s not enough, you see large die-offs as the algal blooms suffocate or poison local species, thereby significantly reducing biodiversity.

Lead Science Cutie is correct that while you may not see the full effect of ocean eutrophication on a global scale, the ocean is composed of many ecosystems supporting a WIDE variety of life on which eutrophication can have a profound impact. Furthermore, if you dump enough waste in one area (as happens when many ships cover the same routes), it will spread. Even if we took the impact on our fishing industry out of the equation, the kinds of dieoffs that result from that are BAD NEWS.

Fortunately, the effects are reversible. However, we should support high water quality standards to allow such affects to reverse where eutrophication has already occurred, and to prevent it from spreading elsewhere.

Which is why I’m going to link to the fundraiser that started all this:

Protect the ocean from raw sewage

Support if you like.

Sources

Mack, Jeremy. 2015. Lake Scientist. Water Quality. “Eutrophication” April 13, 2015 < http://www.lakescientist.com/lake-facts/water-quality/&gt;

Great Reptilian Minds

So I wanted to do something fun and topical for Easter, like about eggs or something. But then my windshield gave up. And I got sick. So here’s some news about the intelligence of reptiles from the New York Times!

Coldblooded Does Not Mean Stupid

Eye-Saving Witchcraft

Time to learn about some magic folks, but first! A story.

So! Knowing me and my love of sleep, most of my friends are surprised when I tell them my favorite job was a research position that involved waking up at 4:30 am. But it was really the best: I got to stomp all over the prairie and wrangle critters (for science!) and everything. I only stumbled over a rattlesnake once. It did require some special equipment on my part, however. Namely cacti-resistant boots, cargo pants (tip: if you’re doing field work, get a pants with pockets big enough to hold a Nalgene. It’s worth it and you’ll thank me later) and sunglasses. I couldn’t get just any sunglasses, though. I was working outside for up to 11 hours, that is a LOT of sun exposure and my eye sight is bad enough without throwing sun damage into the mix. The solution for me was polarized sunglasses (also a hat).

If you’ve lived in a place with any significant amount of sun, you’ve probably seen polarized sunglasses at the store. If you grew up in a place that’s as damp, grey and dark as if it were being swallowed by a giant oyster, you probably haven’t. Or you didn’t until you moved to a place with sun and got a job that had you working outside all day (COUGH COUGH). To understand polarized lenses, you need to understand light.

Light has electric fields that move in waves and these waves acan be oriented in all different directions. Light from a lamp or the sun is like this and thus is unpolarized light. Reflective surfaces can polarize light so that it all travels in one orientation: horizontally. Besides being damn bright and annoying, this light can damage your vision. To combat this, you can get polarized lenses. Polarized lenses have a coating of polymers all aligned parallel to one another. This coating only allows light to pass through that has an electric field perpendicular to the orientation of the polymers.

Scary diagram, but I want you all to see the important bits the official way, first. Namely, the orientation of the wave (the transmission axis of energy) and the direction it flows in.

Simplified diagram

You would think that the light would need to be oriented parallel to the polymers, but such light waves actually get absorbed by the polymers. Anyway, the result is that half of unpolarized light is blocked, while polarized light from glare is virtually eliminated.

Eye saving MAGIC.

Although polarized lenses are expensive, they are very much worth it for protecting your sight if you spend a lot of time in the sun.

Oh, FACT: lots of companies can say they sell polarized lenses even if they don’t. To tell for sure, find a highly reflective surface or a monitor screen and tilt your head to the side. Looking at it normally, it won’t be very bright, but after you tilt your head all the way to the side, the surface should be almost black.

Sources

–. 2012. “Polarization of Light.” Physics. Whitman College. Walla Walla, WA. Lecture.

Tyson, Jeff.  “How Sunglasses Work” 14 July 2000.  HowStuffWorks.com. <http://science.howstuffworks.com/innovation/everyday-innovations/sunglass.htm&gt;  02 April 2015.

Image Credits

Prof Josh (seriously cannot remember his name, someone HELP) for 1^st.

Heartland Optical for 2^nd.

CTS Wholesale Sunglasses for 3^rd.