London: Earth's oxygen could dramatically fall due to change in ocean temperature of just several degrees, which may likely result in the mass mortality of animals and humans, a new study has claimed.
Falling oxygen levels caused by global warming could be a greater threat to the survival of life on Earth than flooding, according to researchers from the University of Leicester in the UK.
The study 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.
"Global warming has been a focus of attention of science and politics for about two decades now," Sergei Petrovskii, Professor at Leicester's Department of Mathematics, 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," said Petrovskii.
"However, it now appears that this is probably not the biggest danger that the warming can cause to the humanity," he said.
"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," said Petrovskii.
The team 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.
The research was published in the journal Bulletin of Mathematical Biology.