By Henry's Law ($K=\frac{x}{p}$), we know that increasing the partial pressure of a gas also increases its solubility on liquids.
Now a lot of sources (this, for instance) illustrate this by presenting "the bends", a condition that divers may experience when ascending too quickly due to the rapid decrease of the N$_2$ solubility on the blood.
So, my question is: why is the N$_2$ solubility greater deep on the ocean than on the surface?
Henry's Law says nothing about the total pressure, only about the partial pressure of the gas in question. When deep in the ocean, the pressure rises thanks to the water above, not due to a increase in N$_2$ partial pressure.
Bonus: does this video illustrate a greater CO$_2$ solubility in coke because of the greater total pressure? I feel like this is the same situation. Why would the CO$_2$ partial pressure be greater?