Oceanography

Dissolved gases in sea water

Gases in seawater include nitrogen (N₂), Oxygen (O₂), Carbon dioxide (CO₂), hydrogen(H₂), and the noble gases argon(Ar),neon (Ne), and helium (He). Nitrogen and the three noble gases are inert (unreactive) and rarely involve directly in plant photosynthesis. In contrast, levels of dissolved (O₂) and (CO₂) are greatly influenced by photosynthesis and respiration of organisms. Therefore they vary greatly in space and time depending on the activities of plants and animals and are regarded as non conservative.

Gas	In Dry Air (%)	In Surface Ocean Water (%)	Water-Air Ratio
Nitrogen (N2)	78.03	47.5	0:6
Oxygen(O2)	20.99	36.0	1:7
Carbon dioxide(CO2)	0.03	15.1	5.03:3
Argon (Ar), hydrogen(H2), neon (Ne) and helium (He)	0.95	1.4	1:5