Supercomputer predicts humans will face a ‘triple whammy’ extinction event
Mammals will live on 8-16% of the land
This is how the world ends – not with a bang, but a ‘triple whammy’ event, according to scientists.
A combination of failing food supply, rising sea levels and areas of the planet becoming too hot to live will ultimately lead to almost all mammals, including humans, to die out.
However, the cause may not be what you imagine.
While climate change is a very real threat to today’s population, this apocalyptic scenario, predicted by a supercomputer, will be caused by all the continents crashing into each other to form one giant landmass.
A hot, dry and largely uninhabitable supercontinent – luckily 250 million years from now.
By this point in the future, the Sun will be brighter and warm the Earth more, while the supercontinent formation will lead to more frequent volcanic eruptions that will produce high releases of carbon dioxide (CO2).
Together this will lead to the Earth being between 40 to 50C.
Lead author Dr Alexander Farnsworth, from the University of Bristol, said: ‘The newly-emerged supercontinent would effectively create a triple whammy, comprising the continentality effect, hotter Sun and more CO2 in the atmosphere, of increasing heat for much of the planet.’
Continentality is one factor effecting the climate depending on how far areas are from the sea.
‘The result is a mostly hostile environment devoid of food and water sources for mammals,’ said Dr Farnsworth. ‘Humans – along with many other species – would expire due to their inability to shed this heat through sweat, cooling their bodies.’
The international team of scientists applied climate models, simulating temperature, wind, rain, and humidity trends for the next supercontinent. To estimate the future level of CO2, the team used models of tectonic plate movement, ocean chemistry and biology to map out inputs and outputs of the gas.
The model predicts that when the supercontinent – called Pangea Ultima – forms, only between 8% and 16% of the land will be habitable for mammals.
However, co-author Dr Eunice Lo said it was important not to focus to worry about the future scenario, and instead concentrate on the present.
‘It is vitally important not to lose sight of our current climate crisis, which is a result of human emissions of greenhouse gases,’ she said.
‘While we are predicting an uninhabitable planet in 250 million years, today we are already experiencing extreme heat that is detrimental to human health. This is why it is crucial to reach net-zero emissions as soon as possible.’
What is carbon dioxide?
- Carbon dioxide (CO2) is a heat-trapping gas that comes from mining and burning fossil fuels, wildfires, and natural processes like volcanic eruptions
- It has no taste, colour or smell
- Since the 18th century, human activities have raise CO2 levels by 50%
- The gas is needed to keep the average global surface temperature above freezing, but adding more carbon dioxide to the atmosphere supercharges the natural greenhouse effect, causing global temperature to rise
Dr Farnsworth said: ‘The outlook in the distant future appears very bleak. Carbon dioxide levels could be double current levels.
‘With the Sun also anticipated to emit about 2.5% more radiation and the supercontinent being located primarily in the hot, humid tropics, much of the planet could be facing temperatures of between 40 to 70C.
‘This work also highlights that a world within the so-called “habitable zone” of a solar system may not be the most hospitable for humans depending on whether the continents are dispersed, as we have today, or in one large supercontinent.’
The researchers say that although the Earth will still be in the ‘habitable zone’ in 250 million years, the higher levels of carbon dioxide will make most of the world uninhabitable.
The study was published in the journal Nature Geoscience.