Ocean warming could stifle oxygen production by plankton
If the world needs another good reason for reaching a climate deal in Paris the next few days, it might be spelled out in a new study led by University of Leicester mathematician Sergei Petrovskii.
According to the research, an increase in the water temperature of the world’s oceans of around six degrees Celsius could stop oxygen production by phytoplankton by disrupting the process of photosynthesis. Some climate models suggest that level of warming could happen by 2100 without steep cuts in greenhouse gas emissions.
“Global warming has been a focus of attention of science and politics for about two decades now,” Professor Petrovskii said. “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,” he explained.
“About two-thirds of the planet’s total atmospheric oxygen is produced by ocean phytoplankton … 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.”
Petrovskii and fellow researchers developed a new model of oxygen production in the ocean that takes into account basic interactions in the plankton community, such as oxygen production in photosynthesis, oxygen consumption because of plankton breathing and zooplankton feeding on phytoplankton.
While mainstream research often focuses on the CO2 cycle, as carbon dioxide is the agent mainly responsible for global warming, few researchers have explored the effects of global warming on oxygen production.