As the world struggles to find effective ways to limit carbon emissions and slow global warming, a recent study has found that the stakes may be higher than anyone has realized. According to Sergei Petrovskii, an applied mathematics professor at the University of Leicester in the United Kingdom, an unchecked rise in global temperatures could end up drastically reducing the amount of breathable oxygen in the planet’s atmosphere, threatening life on Earth as we know it.
In a study published late last year in the Bulletin of Mathematical Biology, Petrovskii ran computer models looking at the phytoplankton in the world’s oceans, microscopic marine plants responsible for producing two-thirds of the world’s atmospheric oxygen. In examining the ability of phytoplankton to photosynthesize at various temperatures, Petrovskii learned something incredibly troubling — at a certain point, these plants would simply halt oxygen production, leaving the world gasping for breath.
Perhaps the most terrifying part of Petrovskii’s findings is the fact that this catastrophe would come with few, if any, warning signs. If global warming continues unchecked, some scientists estimate we could reach this drastic tipping point as soon as 2100, leaving us with only about 84 years before a mass die-off of human and animal life might occur.
It’s important to note that this is an avoidable, although plausible, catastrophe: this doomsday scenario will only occur if we allow the world’s oceans to warm by a total of 6 degrees Celsius. Most climate scientists warn that to avoid the most disastrous effects of climate change, global temperatures must be halted before they rise more than 2°C above pre-industrial levels, and this is the goal recently adopted by the world’s nations at the Paris climate accord.
That being said, the research is also showing that staying below the 2°C limit is increasingly unlikely unless global emissions can be slashed drastically, and the deals reached during the COP21 talks simply aren’t enough. The Climate Action Tracker, an independent group of European climate experts, estimates that current agreements will put eventual global temperatures at around 2.7°C, far lower than the scenario outlined in Petrovskii’s paper, but high enough to potentially trigger major sea level rise, destroy most coral reefs and glaciers, and permanently alter agricultural cycles around the world.
In other words, though we’re currently on track to avoid an Earth with completely unbreathable air, we’re nowhere near where we need to be to avoid the worst effects of global climate change. Still, lawmakers must absolutely keep the possibility of this catastrophe in mind when crafting environmental policy. All life on Earth may depend on it.
Images via NASA Goddard Space Flight Center