A climatologist at Japan’s Tohoku University ran the numbers and doesn’t think today’s mass extinction event will match the previous five. At least not for many centuries yet.
More than once over the past 540 million years, Earth has lost most of its species in a relatively short geologic time span.
These are known as mass extinction events and often follow them closely climate changesuperheating or supercooling, whether caused by asteroids or volcanic activity.
When Kunio Kaiho tried to measure the stability of Earth’s average surface temperature and the planet’s biodiversity, he found a largely linear effect. The greater the temperature change, the greater the rate of extinction.
For global cooling events, the largest mass breaks occurred when temperatures fell by about 7°C. But for global warming events, Kaiho found that the largest mass extinctions occur at about 9°C warming.
This is higher previous estimatesA temperature of 5.2°C would cause a marine mass extinction on the same scale as the previous ‘big five’.
To put this in perspective, end-of-the-century modern global warming It will increase the surface temperature up to 4.4°C.
Kaiho does not deny that there is much poverty on land and sea is already happening due to climate change; it just doesn’t expect the same loss rate as before.
Still, it’s not just the degree of climate change that puts species at risk. The speed at which it happens is very important.
The largest mass extinction event on Earth occurred at the time, killing 95 percent of known species More than 60,000 years about 250 million years ago. But today’s warming is occurring in a much shorter time frame thanks to human fossil fuel emissions.
Perhaps more species in Earth’s sixth extinction event, not because the magnitude of the warming was so great, but because the changes happened so quickly that many species could not adapt.
“It is difficult to predict the extent of future anthropogenic extinction using surface temperature alone, because the causes of anthropogenic extinction are different from the causes of mass extinctions in geological time” – Kaihu acknowledge.
No matter which way scientists slice the data, it’s clear that many species will become extinct if we don’t stop climate change.
The exact percentage of losses and the timing of these losses are still a matter of debate.
The study was published biogeological sciences.