Science Daily has more on the threat climate change poses to our oxygen supply:
A study led by Sergei Petrovskii, Professor in Applied Mathematics from the University of Leicester’s Department of Mathematics, has shown that an increase in the water temperature of the world’s oceans of around six degrees Celsius — which some scientists predict could occur as soon as 2100 — could stop oxygen production by phytoplankton by disrupting the process of photosynthesis.
Professor Petrovskii explained: “Global warming has been a focus of attention of science and politics for about two decades now. A lot has been said about its expected disastrous consequences; perhaps the most notorious is the global flooding that may result from melting of Antarctic ice if the warming exceeds a few degrees compared to the pre-industrial level. However, it now appears that this is probably not the biggest danger that the warming can cause to the humanity.
“About two-thirds of the planet’s total atmospheric oxygen is produced by ocean phytoplankton — and therefore cessation would result in the depletion of atmospheric oxygen on a global scale. This would likely result in the mass mortality of animals and humans.”