How bad it is going to be for ocean animals if global warming continues in this pace? A new study shows that Life in the oceans could face a mass extinction, almost emptying of the ocean. Accelerating greenhouse gas emissions could culminate in a mass extinction rivalling those in Earth’s past, said the peer-reviewed paper published in the journal Science.
The researchers said that in addition to direct human impacts, including habitat destruction, overfishing, and coastal pollution, marine species are increasingly threatened by climate-driven ocean warming and oxygen depletion.
They said that fossil records showed the previous mass extinction events due to global environmental changes. However, the future of ocean life under runaway climate change remains uncertain, they added. They used ecophysiological modelling, which weighed a species physiological limits with projected marine temperature and oxygen conditions.
THE REAL THREAT
Justin Penn and Curtis Deutsch who evaluated the extinction risk for marine species found that under “business as usual” global temperature increases, marine ecosystems planet-wide are likely to experience mass extinctions potentially rivalling the size and severity of the end-Permian extinction – the “Great Dying” – which occurred roughly 250 million years ago and led to the demise of more than two-thirds of marine animals.
Their modelling patterns also revealed future extinction risk. While tropical oceans are expected to lose the most species under climate change, many will likely migrate to higher latitudes and more favourable conditions to survive. However, polar species are likely to go globally extinct, as their habitats will disappear from the planet entirely.
“Climate change is, in effect, walking species off the ends of the Earth,” said Malin Pinsky and Alexa Fredston in a related Perspective. However, the study also suggests, that reducing or reversing greenhouse gas emissions could reduce extinction risks by as much as 70%. “With a coordinated approach that tackles multiple threats, ocean life as we know it has the best chance of surviving this century and beyond,” Pinsky and Fredston writes.