Ha, this is a bad pun. We are modeling the Denmark Strait Overflow – but in a non-numerical, small-scale-and-playdough kind of way.
More than a year ago, Kjetil and I ran that experiment with a group of high-school students and when writing a post about a much more sophisticated version of this experiment I realized I never documented this one in the first place. So here we go!
Dye is added to the “northern end” of the tank (i.e. the end where the water is being cooled by a sport’s injury cooling pack). As the water cools, it becomes denser and fills up the reservoir on the northern end until it spills over the clay ridge.
This is a very simple demonstration of how overflows actually work.