# Gas concentrations along the gradient from sea level to deep-sea

Studying scuba diving-related phenomenas I thought about how to estimate gases concentration down the sea.

Of course, solubility of gases at, for example, $5$ atm of pressure, can be estimated with Henry's law, i.e

$$S=k\,P_g$$

But this is not the case down the sea, cause there is no gas in equilibrium with sea-water. There should be a way to relate solubility on the deep with the surface pressure, but can't find how.

So, is there any way to estimate gases concentration deep into the sea?

• Gas concentrations down the sea can't be estimated; instead, they must be measured. Equilibrium is of no help here, just like I said. Jun 6 '18 at 23:18
• Yes, and your opinion is valuable @IvanNeretin, but I don't see there is a reason for that. There is no eq but maybe it can be estimated.
– user43021
Jun 6 '18 at 23:22
• It can't. It is below the equilibrium pressure (and well below it, in fact), but that's about it. You can't tell any more than that from the first principles. Can there be a sea of water not containing any gas at all? Why, sure. Can there be a sea nearly saturated with oxygen? Why, sure. Where is the real, actual sea? Someplace between. Jun 6 '18 at 23:25
• @IvanNeretin There should be something like an exponential decrease...(I'm just joking). If there isn't any valuable answer or opinion I'll remove it, but let me wait.
– user43021
Jun 6 '18 at 23:32
• Says who? Why an exponential decrease? In fact, there actually is a decrease, and probably it can be well approximated by a downward exponent, but the reason for this (if any) lies far away from chemistry. Jun 6 '18 at 23:36