New at GrowWNY is “Myth Monday,” where we clear up the cloudiness surrounding important environmental topics and issues. Are the tidbits you’ve heard about the environment true or just a flat out myth? To find out, check back each Monday as we explore commonly misperceived topics!
Myth: The melting, ice-capped, Arctic region is contributing to a rising global sea level on an equal scale as the Antarctic region.
Explanation: Think back to a time, likely recently, when you filled your drinking glass with water and ice. If you can’t remember, next time you fill up on ice water, take note of the water level while the ice is still floating in the glass. Set your drink down for about an hour or so and check the line of the water level again. If all has gone according to the laws of physics and thermodynamics, then you should see a glass of water with no ice in it and also no change in the previously recorded water level. Now, what does all this “glass of water talk” have to do with the polar regions of our planet? Let me explain.
Most of the Arctic region of our planet Earth is, basically, a massive floating chunk of ice, much like the ice cubes floating in our glass of water. What this means is that the Arctic ice has already displaced the ocean water, due to its volume and mass already present in the water. This is why we see no change in our glass of ice water once it has melted. While the melting of the Arctic ice is alarming in its own respect, and has its own implications for the Earth’s temperature, intensity of the albedo effect, and beyond, debunking the myth that melting Arctic ice will contribute to global sea level rise equally as its Antarctic counterpart is an important concept to set straight. What truly causes global sea levels to rise most are melting ice sheets that are land-based, like in the majority of the Southern Hemisphere: Antarctica. Because these ice sheets are on land and not currently in the water, this ice has not yet displaced the ocean water. But, when it melts and slides off of the land and into the water—boom—the sea level rise begins as the ice displaces the water and causes it to rise. Now imagine again our melted glass of ice water, at the same height level we noted earlier. Add some more ice to it and watch the water level rise. That is the effect and impact that land-based iced sheets, like Antarctica’s, have on our global sea levels: a stronger influence to raise sea levels than floating sheets of ice.

Same water level as before. Myth busted.



