Physicists predict Earth will become a chaotic world, with dire consequences

Humans aren't just making the Earth warmer; they're also making the climate chaotic, according to a new research.

The new study, published on the preprint archive arXiv on April 21, paints a wide and general picture of the complete possible influence of human activities on the climate. And it isn't a nice image.

According to the study's authors, scientists from the University of Porto's Department of Physics and Astronomy, while the study does not present a complete simulation of a climate model, it does paint a broad picture of where we're headed if we don't curb climate change and our unchecked use of fossil fuels.

"The implications of climate change are well known (droughts, heat waves, extreme phenomena, etc)," study researcher Orfeu Bertolami told Live Science in an email. "If the Earth System gets into the region of chaotic behavior, we will lose all hope of somehow fixing the problem,"  said study researcher Orfeu Bertolami in an email to Live Science.

Climate shifts

Earth's climatic patterns undergo significant shifts on a regular basis, moving from one stable equilibrium to the next. External forces such as changes in Earth's orbit or a huge increase in volcanic activity are generally responsible for these adjustments. However, previous research indicates that we are now entering a new phase, one that is fueled by human activity. As we pump more carbon into the atmosphere, we are ushering in a new Anthropocene epoch, a time of human-influenced climate systems unprecedented on our planet.

The emergence of the Anthropocene was treated as a phase shift in the new study. Most people are familiar with phase transitions in materials, such as when an ice cube melts into water and changes phase from solid to liquid, or when water evaporates into a gas. However, phase transitions may occur in a variety of systems. The system in this example is the Earth's climate. Seasons and weather are predictable and regular in a particular climate, and a climatic phase shift results in a new pattern of seasons and weather. When the climate goes through a phase transition, it indicates the Earth's patterns are changing suddenly and rapidly.

Logistics problems

If human activity causes a phase transition in Earth's climate, it indicates the planet is developing a new set of weather patterns. One of the most serious issues in climate research is predicting what such patterns will look like.

What is the future of the Earth's climate? That is very dependent on the nature of our activities during the next few decades. The researchers concluded in the report that drastically lowering carbon emission would result in different results than doing nothing at all.

The researchers used a mathematical technique called a logistic map to account for the many courses and options that humankind may take. The logistic map is useful for depicting situations in which a variable can expand but eventually approaches a limit, such as the quantity of carbon in the atmosphere. Scientists frequently use the logistic map to describe animal populations, for example: Animals can keep giving birth and multiplying, but there comes a point when they eat all of the food available in their environment (or their predators get too hungry and consume them).

Our impact on the environment is undeniably increasing, and has been for more than a century. According to the experts, it will eventually approach a limit. For example, the human population can only increase to a certain size and there can only be so many carbon-emitting activities before pollution degrades the ecosystem. Carbon production will hit a maximum limit at some point in the future, and the researchers discovered that a logistic map can accurately predict that trajectory.

Everything is chaos

The researchers looked examined how the human logistic map would change over time, based on a range of factors such as our population, the implementation of carbon reduction initiatives, and the development of newer, more efficient technology. They utilized what they learned about human carbon output over time to look at how Earth's climate will change as a result of the human-driven phase shift.

In the best-case scenario, Earth's climate stabilizes at a new, higher average temperature once mankind achieves its carbon production limit. This increased temperature is hazardous for mankind in general because it causes rising sea levels and more extreme weather occurrences. But it's at least stable: The Anthropocene appears to be similar to prior climatic epochs, if warmer, and it will continue to have predictable weather patterns.

However, under the worst-case scenarios, the researchers discovered that the Earth's climate causes pandemonium. Mathematical chaos, indeed. There is no equilibrium and no repeated patterns in a chaotic system. Seasons would shift dramatically from decade to decade in a volatile environment (or even year to year). During certain years, there would be unexpected bursts of intense weather, while others would be entirely silent. Even the average Earth temperature may change dramatically, swinging from colder to hotter times in a matter of days. It would become hard to predict which way the Earth's climate is heading.

"A chaotic behavior means that it will be impossible to predict the behavior of Earth System in the future even if we know with great certainty its present state," Bertolami explained. "It will mean that any capability to control and to drive the Earth System towards an equilibrium state that favors the habitability of the biosphere will be lost." 

Most alarming, the researchers discovered that if the Earth's atmosphere reaches a certain critical temperature, a feedback cycle might set up, making a catastrophic outcome unavoidable. There are some evidence that we have already past that tipping point, but it is still possible to avoid climate catastrophe.