Turning Our Back on the Ocean

Wolfe Rygaard

As I sat in the classroom, reading my book about water conservation to a group of grade schoolers, I couldn’t help but notice the puzzling look on one of the student’s faces. I wondered if the words in my book were too advanced. Maybe I failed to enunciate properly. Whatever the cause, each time I scanned the group after turning a page, that same look was on his face. When I turned the last page, I asked if there were any questions. Every hand shot up, but his. That was until I answered two other questions. Perhaps I should’ve called on the kids who raised their hands first but I was dying to figure out what was going on inside this kid’s head. At long last, I found out when he asked “But… the earth is like… covered in water?” Hopefully, he couldn’t tell from my smiling face, but his question made me feel so dumb. In a book about water conservation, I failed to address the reason why water is so valuable in the first place. Life doesn’t give us second chances but it does give us a chance to right our wrongs. Here is an apology for confusing an innocent grade school kid with a book about water conservation.

Water is the substance that makes life on earth possible. Humans are no exception to this. We use water for cooking, cleaning, agriculture, drinking, and so much more. Despite many of us having the luxury of watching water rush from our faucets whenever we turn the nozzle, UNICEF reports that four billion people experience severe water scarcity for at least one month each year. Furthermore, UNICEF projects that 1 in 4 children will be living in areas of extremely high water stress by 2040.

Before we attempt to tackle this problem, we must first identify the two types of water: freshwater and salt water. The difference between these two is the amount of salt. Freshwater has a salinity level(measurement of salt concentration) of 0.5ppt(parts per thousand) while salt water has a salinity level of 30ppt or more. When you look at the blue oceans, which hold about 97% of the earth’s water, it seems impossible for water to become scarce. The problem lies in the types of water we identified earlier. The water in the oceans is salt water and humans need freshwater. Doing some quick math(100–97), we find that only 3% of the world's water is freshwater. Of that small 3%, a further 2.5% is locked away in glaciers and polar ice caps. That means all of the humans, and all other life that needs freshwater, share a measly 0.5%.

The simplest solution would be to just use ocean water. How much of a difference can salt make after all? Well, that difference in salt concentration can be the difference between life and death. Allow me to explain. Sodium, the main component of salt, is actually key to maintaining a healthy body. However, it’s the dose that makes the poison. The kidneys, which typically flush out excess sodium using bodily water, struggle to flush the sodium from seawater as the salinity is around four times higher than that of bodily fluids. As your body keeps telling your kidneys to flush the extra sodium from your body, water is pulled from the cells. In short, you may be drinking water but your body is releasing more water than you’re drinking. This net loss of water can lead to dehydration and, if continued, will lead to death. So drinking ocean water seems to be off the table.

The next best thing would be taking the salt out of the water. This process, called desalination, can take many forms, the most common being distillation.

So let’s say we’re using salt water. We have two components, salt, and water. Each component has a unique boiling point. The boiling point of water is 212F (100C) which is significantly lower than sodium’s boiling point. Based on this information, boiling seawater at 212F should see all the water evaporate while the salt remains solid. The vapors can then be collected, cooled, and used. Although this works in theory, and in practice as desalination plants do exist, the logistics are lagging behind. Think about the last time you made pasta or rice. How long did it take for that pot of water to boil? Probably, an eternity and then some. Now imagine trying to boil all of the water you use on a daily basis. Not only would that take forever, but it would also be energetically expensive. Desalination also has another problem. What do you do with the extra salt? The leftover liquid, known as brine, is supersaturated with salt and has no real uses. The most common answer is to just throw it in the ocean because the ocean is already salt water. However, just as the small change in salinity was harmful to us, dumping brine into the ocean can harm the organisms living in those waters. This can be especially worrisome when you take into account the size of some desalination plants.

If we can’t use it and we can’t change it, our only solution is to save our precious water. Even if it’s something small like turning off your faucet when brushing your teeth, every drop of water counts.

To that poor kid who I confused during story time, I hope you accept my apology.

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I am an environmental scientist who currently resides in Puerto Rico. I’m also passionate about basketball and Tottenham Hotspur.

Puerto Rico State

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