Also called the Permian-Triassic extinction event The Great Death, has certainly earned its nickname. It was the largest mass rift to wipe out the geological record 83 and 97 percent all species that live on earth. Although the exact cause is debated, it is excessive perhaps volcanic activity that cooked the planet was fingered as the main culprit.
But somehow, despite being hit by asteroids and cosmic radiation, life has continued on this planet for almost four billion years. Our planet including a The Sixth Mass ExtinctionDriven by a wave of human activity that has led to the extinction of thousands of species, the question of how this works becomes even more pressing, especially how the Earth recovers from large-scale disasters or extreme changes in atmosphere or climate. .
It turns out that the answer may be, in part, stranger than anyone imagined. A new study in the journal Advances in science It shows that the Earth can regulate its temperature over hundreds of thousands of years. In other words, there are large-scale geological processes that seem to absorb carbon dioxide over a large time scale. However, the time scale to correct the sudden increase in carbon dioxide from burning fossil fuels is too long, meaning the mechanism will not save us. climate change.
“You have a planet whose climate has undergone such dramatic external changes. Why has life survived all this time?”
Constantin Arnscheidt and Daniel Rothman, two researchers from the Massachusetts Institute of Technology in Cambridge, crunched data from multiple databases documenting global temperatures over the past 66 million years. These paleoclimate records include ice cores from Antarctica and the chemical composition of prehistoric marine fossils, which can tell us a lot about what Earth’s atmosphere was like in the distant past.
“All of this research is only possible because there have been great advances in improving the resolution of these deep-sea temperature records,” Arnscheidt said. statement. “We now have data going back 66 million years, with at most thousands of years between data points.”
Two MIT scientists have found a powerful example of how Earth uses feedback loops to keep its temperature in a range where life can thrive. However, this happens over hundreds of thousands of years, so while this means our planet will bounce back from anthropogenic climate change, it won’t happen soon enough to save us.
“One argument is that we need some kind of stabilizing mechanism to keep the temperature suitable for life,” Arnscheidt said. “However, no such mechanism has ever been proven from the data to consistently drive Earth’s climate.”
This finding has major implications for our understanding of the past, but also for how global warming is shaping the future of our home world. It even helps to better understand the evolution of planetary temperature, which can lead to a search exoplanets inhabited by aliens are more fertile.
“You have a planet with such dramatic external changes in climate. Why has life survived all this time? One argument is that we need some sort of stabilizing mechanism to keep the temperature suitable for life,” Arnscheidt said. “However, no such mechanism has ever been proven from the data to consistently drive Earth’s climate.”
Many scientists have suggested that the Earth has regulated its temperature throughout history, but this has been difficult to prove. In the 1960s, the late inventor and ecologist James Lovelock applied Darwinian processes not to a single organism but to the entire planet to explain how such a complex system evolved. I called it The Gaia hypothesisIt explains how the Earth and its biological systems form feedback loops that keep our planet suitable for living organisms.
This also helped to explain The Weak Sun ParadoxIt was first proposed by astronomers Carl Sagan and George Mullen 1972. In fact, our Sun was much smaller and colder 4.5 billion years ago. Back then, based on our current understanding of stellar life cycles, the Sun would have been about 30 percent dimmer than it is today. This, in turn, would have made Earth too cold for liquid water, preventing life from forming – yet obviously this happened. But how did our rocky world do it?
The answer lies in how carbon cycles around the planet. A prominent theory is that when our planet first formed, the Sun was colder, but had an atmosphere full of carbon dioxide, a powerful greenhouse gas that allowed it to absorb heat.
“On the one hand, that’s good because we know that today’s global warming will eventually be reversed through this stabilizing feedback. But on the other hand, it will take hundreds of thousands of years, so it’s not fast enough to solve our current-day issues.”
a complex process known as silicate wear then removes carbon dioxide from the atmosphere and buries it at the bottom of the ocean. Over time, this cools the planet. Then something like large volcanic eruptions gold people driving, rewarming the planet by pumping more carbon dioxide into the air. Earth balances between too cold and too hot over the years, explaining why some call it Earth Goldilocks Planet.
MIT research is helping to reconcile existing data with this long-standing theory, leading to a better understanding of our past and the consequences of uncontrolled climate change. And it would make sense that if these feedback loops exist on our planet, they could exist in other galaxies as well. hunting for alien creatures.
“On the one hand, it’s good because we know that today’s global warming will eventually be reversed through this stabilizing feedback,” Arnscheidt said. “But on the other hand, it would take hundreds of thousands of years to happen, so it’s not fast enough to solve our modern problems.”
However, Arnscheidt’s model failed to account for this equilibrium over a period of more than a million years, so random chance may have played a large role in the success of life on this rock.
“There are two camps: Some say that random chance is a good enough explanation, while others say there should be stabilizing feedback,” Arnscheidt said. “We can show directly from the data that the answer is probably in the middle. In other words, there was some stabilization, but luck probably also played a role in making Earth continuously habitable.”
It may be a mixture of randomness and feedback loops, such as silicate weathering, which affected Earth’s temperature in the past. But in the future of humanity, it will be free will – our politics, our consumption, our choices – that will drive the warming of the planet forward. And we can perturb these natural systems to such an extent that they fail to equilibrate in a manner similar to prominent theories of potentials. Life on Mars.
In his 2019 book, Lovelock wrote, “The heating of the Sun has been slow enough to allow the evolution of life, a process that takes millions of years. Unfortunately, the Sun is now too hot for the further development of organic life on Earth.”Novacene: The Coming Age of Hyperintelligence.” “The heat output from our star is too great for life to restart as it did in the simple chemicals of the Archaean 4-2.5 billion years ago. If life on earth disappears, it will never start again.”
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