Oxygen supersaturation in the ocean: biological versus physical contributions.

A method based on measurements of dissolved molecular nitrogen, molecular oxygen, and argon can distingish biological from physical contributions to oxygen supersaturation in the ocean. The derived values of biological O(2) production can be used as a check on estimates of total organic productivity measured by instantaneous rates of carbon-14 assimilation. Application to the shallow summer O(2) maxima in the North Pacific gyres shows that about 72% of the O(2) supersaturation maximum at 28 degrees N and about 86% of the maximum at 40 degrees N are due to net photosynthetic production.