When I was in the fifth grade, we learned how bodies of water move by tidal waves. Despite science being my favourite subject in grade school, I found this unit terribly boring and had a hard time focusing. Yet, my knowledge of tidal waves stuck with me throughout all these years, seeping into my curious brain.
The science behind the movement of large bodies can be very complex but breaks down into surface waves and tidal waves. Surface waves are created by the friction between the wind blowing across the water which forces the waves to crest – these movements are tied to our global wind systems. Surface waves allow surfers to hang ten, but they are also responsible for water-related natural disasters caused by severe weather like hurricanes. Surface waves are also influenced by underwater disturbances like earthquakes, landslides, or volcanic eruptions that cause tsunamis.1
Tidal waves, on the other hand, are caused by gravitational pulls between the Earth, moon, and sun. Gravity is influenced by the size of the object and works based on an object’s centre of mass. Tidal force is influenced by the strength of gravity and the distance between objects. “The overall effect of the tidal force is to stretch an object.”2 Being a smaller mass, the moon has a weaker gravitational pull than Earth; however, the side of the Earth closest to the moon will bulge in response to the moon’s gravity, pulling the Earth’s centre of mass towards it. The side of the Earth that is furthest away from the moon will bulge in response since the moon’s gravity has a lesser effect.
In these bulged areas, the tidal force is the strongest, giving us high tides in our oceans and lakes. The tidal force is weakest on the areas being stretched, giving us low tides. Since the Earth rotates, we have two high tides and two low tides every day. Tidal waves fluctuate the sea level by about 1-2 metres every day. Check out the video below for more information on tidal waves!
I don’t exactly remember all this science from the fifth grade; I do remember being confused about high and low tides and drawing my moon chart on the day it was due even though we were supposed to monitor the moon’s cycle for the entire month.
But as I sat alone on the boat ramp of my cottage this past weekend, I watched Lake Erie’s tide ebb and flow. There was a light breeze and as the sun was going down, the moon was becoming more visible. In a calm setting such as this, your mind taps into unique nooks and crannies of your brain, mine reminding me of grade five science class and my appreciation for nature.
I stopped studying science in grade 10 but picked some of it back up when taking Environmental Studies and Introduction to Sustainability in my first year of university. I was never going to switch into a science major but studying science alongside my Arts major helped me recognize the importance of arts and sciences working together.
For instance, understanding tidal forces is not an easy concept, but thanks to communicators like Phil Plait (in the video above), and perhaps myself, we are able to dissect the science and present it to others who do not have an advanced science background.
While my logical left brain tried to remember how the moon’s gravity caused tidal waves, my creative right brain flowed towards existentialism. I thought about how waves thrust water to the shore, draw water back into the massive body, and push more (if not the same) water back to the shore. Watching this ebb and flow made me think of how our lives are also in a constant ebb and flow.
When we desire, we rush towards it. When we’ve reached our desire or find obstacles in between, we are pulled back into the pool of desire only to try to grasp it again. There are certain times where we will be able to reach more of our desires, and there are times where that seems impossible.
Water movement is scientific, yet we are able to attach philosophy and apply it to human existence. Science and philosophy tend not to mix, but I wonder whether we give nature its philosophy or nature gives us our philosophy.
These are my lakeside thoughts.