A long-term record of global mean surface temperature (GMST) provides critical insight into the dynamical limits of Earth’s climate and the complex feedbacks between temperature and the broader Earth system. Here, we present PhanDA, a reconstruction of GMST over the past 485 million years, generated by statistically integrating proxy data with climate model simulations. PhanDA exhibits a large range of GMST, spanning 11° to 36°C. Partitioning the reconstruction into climate states indicates that more time was spent in warmer rather than colder climates and reveals consistent latitudinal temperature gradients within each state. There is a strong correlation between atmospheric carbon dioxide (CO 2 ) concentrations and GMST, identifying CO 2 as the dominant control on variations in Phanerozoic global climate and suggesting an apparent Earth system sensitivity of ~8°C.
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Things are not stable between the mass extinctions - the mass extinction events are just extreme events of high relevance.
The thing is that Earth is constantly shifting in unpredictable ways. There was an interesting paper recently published working to reconstruct the temperature record of the last 500 million years. [1]
The paper concluded that global mean temperatures varied (over time) in a range from 11c to 36c. We're currently around 15. And temperature is but one of countless variables, most all of which are constantly changing.
This makes longterm equilibriums basically impossible because each time things change, it disrupts the existing balance and there will be new winners and new losers.
[1] - https://www.science.org/doi/10.1126/science.adk3705
> We should correlate the "dying" to other times in the last millions/billions of years where the temperature rose tis "quickly".
We certainly would if we found evidence of any similar events in the past. Do you have contradictory info?
> As the Earth moved out of ice ages over the past million years, the global temperature rose a total of 4 to 7 degrees Celsius over about 5,000 years. In the past century alone, the temperature has climbed 0.7 degrees Celsius, roughly ten times faster than the average rate of ice-age-recovery warming.
> Models predict that Earth will warm between 2 and 6 degrees Celsius in the next century. When global warming has happened at various…
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times in the past two million years, it has taken the planet about 5,000 years to warm 5 degrees. The predicted rate of warming for the next century is at least 20 times faster. This rate of change is extremely unusual.
https://earthobservatory.nasa.gov/features/GlobalWarming/pag...
> The findings also reveal that the Earth's current global temperature of 59 degrees Fahrenheit is cooler than Earth has been over much of the Phanerozoic. But greenhouse gas emissions from human-caused climate change are currently warming the planet at a much faster rate than even the fastest warming events of the Phanerozoic, the researchers say. That speed of warming puts species and ecosystems around the world at risk and is causing a rapid rise in sea level. Some other episodes of rapid climate change during the Phanerozoic have sparked mass extinctions.
https://news.arizona.edu/news/study-over-nearly-half-billion...
https://www.science.org/doi/10.1126/science.adk3705
I will not argue about definitions of terms, but there was a recent study that I found linked on washingtonpost.com I believe (Edit: found, added).
WP article: https://www.washingtonpost.com/climate-environment/2024/09/1... (https://archive.md/RM8ez)
> ...humans evolved during the coldest epoch of the Phanerozoic [the time period from 540 million years ago to the present], when global average temperatures were as low as 51.8 F (11 C).
> “We built our civilization around those geologic landscapes of an icehouse,” Judd [one of the study's authors] said.
Study (restricted): "A 485-million-year history of Earth’s surface temperature" --…
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https://www.science.org/doi/10.1126/science.adk3705
> Partitioning the reconstruction into climate states indicates that more time was spent in warmer rather than colder climates
Look at the graph - our time is on the very right. We humans developed and are still living in unusually cold times for this planet, historically.
The modern era of humans roughly coincides with Earth's coldest period over the last 485M years: https://www.science.org/doi/10.1126/science.adk3705
Even some of the worst predictions for where temperatures are headed before we get close to Net Zero emissions don't put us above historical averages.
To be clear, if the worst predictions come to light, that will be bad for people. But the planet will be fine.
I doubt some extra solar radiation will turn the Earth into Venus or Mars.
Recent work has demonstrated substantial gains on many NLP tasks and benchmarks by pre-training on a large corpus of text followed by fine-tuning on a specific task.
The Fermi paradox is the conflict between an expectation of a high {\em ex ante} probability of intelligent life elsewhere in the universe and the apparently lifeless universe we in fact observe.
Despite their massive size, successful deep artificial neural networks can exhibit a remarkably small difference between training and test performance.
In honor of Alan Turing's hundredth birthday, I unwisely set out some thoughts about one of Turing's obsessions throughout his life, the question of physics and free will.