Let's examine our biochemical reaction for life in the sea, and on this earth, in general.
6H2O + 6CO2 + nutrients + energy <=> C6H12O6
The rate at which this reaction takes place provides a fundamental control on the amount
of life in the sea.
Are any of the conditions on the left side of
the reaction in short supply in the sea such that the amount of life in the ocean may
be limited in places? (organic carbon = carbon in living things)
H2O or water? Clearly is not -- since there is plenty of water. Indeed it
is commonly believed that life on our planet began in the sea more than 3.3 billion years
CO2, carbon dioxide? --- there is plenty of carbon dioxide dissolved in sea
water, especially in the cold waters of the subpolar and polar regions.
Energy? No problem here either, at least not in the sunlight surface waters of the mixed
layer during the long days of spring and summer.
So it looks like nutrients may be the main factor that limits the amount of life in the