A climatologist at Tohoku University in Japan has jotted down the numbers and doesn’t think that today’s mass extinction event will be the same as the previous five events. At least not for the next few centuries.
More than once in the last 540 million years, Earth has lost most of its species in relatively short geological time periods.
These are known as mass extinction events, and often follow after them Climate changeeither due to extreme warming or extreme cooling caused by asteroids or volcanic activity.
When Kunio Kaeo tried to measure the stability of the Earth’s average surface temperature and the planet’s biodiversity, he found a mostly linear effect. The greater the temperature change, the greater the extinction rate.
For global cooling events, the largest mass extinctions occur when temperatures drop by about 7 °C. But for global warming events, Kaiho found that the largest mass extinctions occurred at around 9°C warming.
It’s much higher than Previous Estimateshowed that a temperature of 5.2 °C would cause a major oceanic mass extinction, on par with the previous ‘Big Five’.
To illustrate, by the end of this century, modern global warming will On track to increase surface temperature to 4.4°C.
“9 degrees Celsius global warming won’t show up in in Anthropos At least up to 2500 under the worst case scenario “Kayo Expecting.
Kaiho does not deny that many extinctions on land and at sea have been caused by climate change; He just didn’t expect the same percentage of losses as before.
However, it’s not just the rate of climate change that puts this species at risk. The speed at which it occurs is very important.
The largest mass extinction event on Earth killed 95 percent of the species known at the time More than 60,000 years About 250 million years ago. But today’s warming is happening on a much shorter timescale thanks to human emissions of fossil fuels.
Perhaps more species will die in Earth’s sixth extinction event not because the scale of warming is too great, but because change is happening so fast that many species are unable to adapt.
“Predicting the magnitude of future anthropogenic extinctions using only surface temperatures is difficult because the causes of anthropogenic extinctions are different from the causes of mass extinctions in geological time,” Caillou said. confess.
No matter how scientists share the data, it’s clear that many species are doomed to extinction unless we can stop climate change.
The exact percentage of losses and the timing of the losses are still under discussion.
This study was published in biological science.
–
