Some species of marine diatoms (single cell, free floating, ocean autotrophic organisms) produce as much as 40% of the earth’s total atmospheric oxygen (O2) while at the same time consuming atmospheric carbon-dioxide (CO2). Atmospheric CO2 becomes dissolved in the ocean waters and these marine diatoms use it, plus sunlight as an energy source, to reduce carbon to produce organic foodstuffs and O2 through photosynthesis alone. Luckily, these diatoms adapt to produce more O2 (at a lower photonic energy consumption) as the CO2 in the atmosphere increases. This has the opposite effect from that of burning fossil fuels and helps to effect a counterbalance to the human burning of carbon fuels. Such an effect has not been heretofore considered in projections of global warming; and this omission may represent a major miscalculation in long term global temperature rise due to a projected atmospheric CO2 accumulation.