They’re kind of behind the times - the last time I was in the Ocean I found it IMPOSSIBLE to breath without lifting my head out of the water. There already isn’t any Oxygen in the water.
Actually, that “O” part of H2O stands for Oxygen. We’re just not equipped with the apparatus necessary to extract it. But as for the main point, funny how marine life seemed to do quite well back in the day when global CO2 (there’s that pesky “O” again, this time in a form available to plants) was several times current levels. In other words ... Shivali, you are so full of shit.
This is just plain not true. There is lots of dissolved oxygen in the water. Fish separate it out with gills and do just fine. But, just like fish suffocate out of water, your lungs are not made to process oxygen dissolved in water and you drown in water.
Bob, every ocean on the planet is at least 1/3 oxygen.