Mechanistic paradigms exist for increased pCO2 to result in increased photosynthesis in corals. For instance, Roos (1967) found that growth of Porites astreoides does not increase in proportion with increasing light intensity beyond the compensation threshold (when the oxygen production of photosynthesis meets oxygen consumption of respiration) because the availability of carbon dioxide does not keep pace with increasing high light intensities. Hence at high light levels, increased pCO2 should increase the rate of photosynthesis if this paradigm is correct.