Published on July 3rd, 2018 | by Steve Hanley0
Climate Change & The Alien Apocalypse
July 3rd, 2018 by Steve Hanley
We don’t spend very much time here at CleanTechnica talking about astrophysics and biogeochemistry, but there are people who do enjoy thinking about such matters. Adam Frank, a professor of physics and astronomy, and Jonathan Carroll-Nellenback, a senior computational scientist at the University of Rochester, are two such folks. Together with astrophysicist Martina Alberti of the University of Washington and Axel Kleidon of the Max Planck Institute for Biogeochemistry, they have published a report in the journal Astrobiology entitled The Anthropocene Generalized: Evolution of Exo-Civilizations and Their Planetary Feedback.
First, let’s define our terms, shall we? According to Wikipedia, anthropocene means “relating to or denoting the current geological age, viewed as the period during which human activity has been the dominant influence on climate and the environment.” Professor Frank says, “Astrobiology is the study of life and its possibilities in a planetary context. That includes exo-civilizations or what we usually call aliens.”
The authors are among the first to ask what is really the threshold question when it comes to discussing climate change — how do we know if sustainability is even possible? Are there planets in the universe that have developed sustainable civilizations or does every civilizations consume all the available resources and then disappear after a few centuries or millenia? “If we’re not the universe’s first civilization,” Frank says, “that means there are likely to be rules for how the fate of a young civilization like our own progresses.”
As reported by Science Daily, he and his colleagues suggest a civilization changes the planet’s conditions at it consumes resources, which means civilizations and planets don’t evolve separately from one another. Rather they evolve interdependently, and the fate of our own civilization depends on how we use Earth’s resources.
In order to illustrate how civilization/planet systems evolve together, Frank and his collaborators developed a mathematical model to show the ways a technologically advanced population and its planet might develop together. By thinking of civilizations and planets — even alien ones — as a whole, they say researchers can better predict what might be required for humanity to survive on Earth.
“The point is to recognize that driving climate change may be something generic,” Frank says. “The laws of physics demand that any young population, building an energy-intensive civilization like ours, is going to have feedback on its planet. Seeing climate change in this cosmic context may give us better insight into what’s happening to us now and how to deal with it.”
The researchers developed four potential scenarios that might occur in a closed civilization/planet system such as we have here on Earth.
- Die-off: The population and the planet’s state (indicated by something like its average temperature) rise very quickly. Eventually, the population peaks and then declines rapidly as the rising planetary temperature makes conditions harder to survive. A steady population level is achieved, but it’s only a fraction of the peak population. “Imagine if 7 out of 10 people you knew died quickly,” Frank says. “It’s not clear a complex technological civilization could survive that kind of change.”
- Sustainability: The population and the temperature rise but eventually both come to steady values without any catastrophic effects. This scenario occurs in the models when the population recognizes it is having a negative effect on the planet and switches from using high-impact resources, such as oil, to low-impact resources, such as solar energy.
- Collapse without resource change: The population and temperature both rise rapidly until the population reaches a peak and drops precipitously. In these models, civilization collapses, although it is not clear if the species itself completely dies outs.
- Collapse with resource change: The population and the temperature rise, but the population recognizes it is causing a problem and switches from high-impact resources to low-impact resources. Things appear to level off for a while, but the response turns out to have come too late, and the population collapses anyway.
“The last scenario is the most frightening,” Frank says. “Even if you did the right thing, if you waited too long, you could still have your population collapse.”
The mathematical models developed by the researchers are based in part on case studies of extinct civilizations such as the inhabitants of Easter Island. People began colonizing the island between 400 and 700 AD. The population grew to a peak of 10,000 sometime between 1200 and 1500 AD. By the 18th century, however, the inhabitants had depleted their resources and the population dropped drastically to about 2,000 people.
The Easter Island population die-off relates to a concept called carrying capacity, or the maximum number of species an environment can support. The Earth’s response to civilization building is what climate change is really all about, Frank says. “If you go through really strong climate change, then your carrying capacity may drop, because, for example, large-scale agriculture might be strongly disrupted. Imagine if climate change caused rain to stop falling in the Midwest. We wouldn’t be able to grow food, and our population would diminish.”
The models are not yet sophisticated enough to accurately predict the fate of the Earth. The researchers will now attempt to refine their models so they can come up with better answers. In the meantime, Frank issues a sober warning. “If you change the Earth’s climate enough, you might not be able to change it back,” he says. “Even if you backed off and started to use solar or other less impactful resources, it could be too late, because the planet has already been changing. These models show we can’t just think about a population evolving on its own. We have to think about our planets and civilizations co-evolving.”
Precious little of that thinking is going on in the highest circles of world governments, where officials still do not grasp that the continued use of fossil fuels is a death sentence for every living thing on Earth. Profits and shareholder value will be meaningless when we are all dead.