Climate change could prepare the Earth’s oceans for one of the worst mass extinction events in the planet’s history within the next 300 years, according to a new study published Thursday. However, it is still possible to moderate the risk to marine animals if greenhouse gas emissions are controlled.
- The Princeton University researchers’ study, published in the journal Science, used a model to estimate how different levels of global warming greenhouse gas emissions would cause marine life to lose habitat and become extinct.
- Under a scenario with high emissions that would lead to an increase in air temperature of 4.9 degrees Celsius over the next century and continue to rise thereafter, about 30% of the animals living in the oceans could disappear in 2300, an event that would “compete with the severity of past mass extinctions” over hundreds of millions of years.
- These extinctions would be triggered by a rise in sea temperature, which threatens marine animals around the world by depriving them of their usual habitat and reducing the oxygen content of the water.
- However, under a low-emission scenario that causes the air temperature rise to stop at 1.9 degrees Celsius by 2100, the severity of marine animal extinction will drop by 70%, according to the study.
“The silver is that the future is not written in stone,” Justin Penn, a Princeton postdoc who co-authored the study with geoscience professor Curtis Deutsch, said in a published paper by Princeton. “There is enough time to change the trajectory of CO2 emissions and prevent the amount of warming that would cause this mass extinction.”
Greenhouse gas emissions such as carbon dioxide trigger global temperature rises, and experts have long warned that this trend could pose serious risks to marine and terrestrial life. Under the 2015 Paris Agreement, hundreds of countries agreed to prevent global warming from exceeding 1.5 to 2 degrees Celsius above pre-industrial levels – similar to the low-emission scenario in Tuesday’s survey – but it may turn out that become difficult to achieve that goal. In a report released in February, the Intergovernmental Panel on Climate Change (IPCC) warned that temperatures could rise by 1.5 degrees Celsius over the next two decades, which is likely to cause severe weather and large-scale extinction, and that the possibility of Preventing further damage by reducing emissions is “short and very limited”.
According to the study, the risk of extinction is not evenly distributed across all of the planet’s oceans. Marine animals located near the North and South Poles are most vulnerable, as the cold-water habitats they depend on can gradually disappear completely, while tropical species can survive by migrating north and south as temperatures rise.
Even without taking into account climate change, man-made phenomena such as overfishing and pollution have put pressure on marine life. But Thursday’s study estimates that if greenhouse gas emissions remain high, the impact of climate change on marine life could overshadow the negative effects of all other man-made threats to the world’s oceans. Her 2100.
Article translated from Forbes US – Author: Joe Walsh
<< Læs også: Earth Day 2022: Hvordan tager små virksomheder handling for planeten? >>>