What is Thermohaline Circulation?
Story time!!! As promised in my previous blog, I am back today to walk you through a fascinating mechanism controlling ocean current movements known as the ‘thermohaline circulation’.
I will not keep you waiting any longer, let’s dive into the ocean. Oops! I meant the topic ;)
The Definition of “Thermohaline”
Two key factors controlling deep ocean circulation are highlighted in the name itself. In the word thermohaline, ‘thermo’ stands for temperature, and ‘haline’ stands for salinity or salt content of the water. Colder or denser (i.e., higher salt content) seawater sinks, while hotter or less dense seawater floats.
The Great Ocean Conveyor Belt
Going by the definition given above, we can sum up that the colder and saltier waters in the polar regions will sink to the deeper ocean, while the opposite is true for warmer waters closer to the equator.
What we need to remember here is that ocean waters don’t remain fixed in their positions. In fact, they are continuously moving around the globe in a specific pattern, identified as the Great Ocean Conveyor Belt. Through this, the ocean current travels at a rate of several centimeters per second, and helps in evenly distributing heat across the world and regulating climate.
Now, think about how global warming interferes with this. Ice sheets and glaciers in the polar regions, composed of freshwater, are fast melting with rising ambient temperatures. This releases a fresh stream of water into the ocean, which ends up floating rather than sinking due to lower salinity. As a result, the ocean current starts circulating at a slower rate.
What does this mean for the planet? Slower-moving ocean currents will mess with regional climates, induce extreme weather patterns, aggravate glacier melting events, expedite sea level rise, and cause many other devastating consequences to the planet and its people.
To make it easier for you to visualize what I have explained, watch the quick video below that illustrates the ocean current movements and how they are affected by global warming.
Do you now understand the term ‘thermohaline circulation’ better? If you would like to learn about similar topics on nature and environmental sustainability, stay tuned and follow this page for more content coming your way soon! See you in the next blog :)
