Humans are not only warming the Earth, they are making the climate chaotic, a new study suggests.
The new research, which was published on April 21 in the prepress database arXiv (opens new tab), draws a broad and general picture of the total potential impact of human activity on the climate. And the picture is not pretty.
Although the study does not present a complete simulation of a climate model, it does draw a broad outline of where we are going if we do not reduce climate change and our uncontrolled use of fossil fuels, according to the study’s authors, scientists in the Department of Physics and Astronomy at the University of Porto in Portugal. .
“The implications of climate change are well known (droughts, heat waves, extreme events, etc.),” study researcher Orpheus Bertolami told Live Science in an email. “If the Earth system enters the region of chaotic behavior, we will lose all hope of fixing the problem in some way.”
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Climate change
The Earth periodically undergoes massive changes in climate patterns, moving from one stable equilibrium to another. These changes are usually motivated by external factors such as changes in Earth’s orbit or a massive increase in volcanic activity. But previous research suggests that we are now entering a new phase, driven by human activity. As humans pump more carbon into the atmosphere, we are creating a new era of the Anthropocene, a period of man-influenced climate systems, something our planet had never experienced before.
In the new study, researchers modeled the introduction of the Anthropocene as a phase transition. Most people are familiar with the phase transitions in materials, for example, when an ice cube changes phase from a solid to a liquid when it melts in water, or when water evaporates into a gas. . But phase transitions also occur in other systems. In this case, the system is the Earth’s climate. A given climate provides regular and predictable weather stations and weather, and a phase transition in the climate leads to a new pattern of seasons and weather. When the climate goes through a phase transition, it means that the Earth is experiencing a sudden and rapid change in patterns.
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Logistics problems
If human activity is driving a phase transition in the Earth’s climate, it means that we are causing the planet to develop a new set of meteorological patterns. How these patterns will be is one of the most pressing issues in climate science.
Where is the Earth’s climate headed? It depends a lot on what exactly our business will be like over the next few decades. Drastically reducing carbon production, for example, would lead to different outcomes that would not change anything, the researchers wrote in the study.
To take into account the different trajectories and choices that humanity might make, the researchers used a mathematical tool called a logistic map. The logistic map is excellent for describing situations in which some variable, such as the amount of carbon in the atmosphere, can grow, but naturally reaches a limit. For example, scientists often use the logistic map to describe animal populations: animals can continue to give birth, increase their numbers, but reach a limit when they consume all the food in their environment (or their predators pass too hungry and consume them).
Related: The 5 events of mass extinction that shaped the history of the Earth
Our influence on the environment is growing, and has been for more than a century. But naturally, it will reach a limit, according to researchers. For example, the human population can only grow so much and can only have so many carbon-emitting activities; and pollution will end up degrading the environment. At some point in the future, carbon production will reach a peak, and researchers found that a logistic map can capture the future trajectory of this carbon production very well.
Everything is chaos
The researchers explored different ways in which the human logistics map could evolve, depending on various factors such as our population, the introduction of better and more efficient carbon reduction strategies and technologies. Once they discovered how human carbon production would evolve over time, they used it to examine how the Earth’s climate would evolve through the human-driven phase transition.
At best, once humanity reaches the limit of carbon production, the Earth’s climate stabilizes at a new higher average temperature. This higher temperature is generally bad for humans, because it still leads to higher sea levels and more extreme weather events. But at least it’s stable: the Anthropocene looks like earlier climatic ages, only warmer, and will still have regular, repeatable weather patterns.
But in the worst case, the researchers found that the Earth’s climate leads to chaos. True, mathematical chaos. In a chaotic system, there is no balance or repeatable patterns. A chaotic climate would have seasons that change enormously from one decade to the next (or even from one year to the next). Some years would experience sudden flashes of extreme weather, while others would be completely quiet. Even the average temperature of the Earth can fluctuate wildly, from colder to warmer periods in relatively short periods of time. It would be utterly impossible to determine in which direction the Earth’s climate is headed.
“Chaotic behavior means that it will be impossible to predict the behavior of the Earth’s system in the future, even if we know its current state with great certainty,” Bertolami said. “It will mean losing any ability to control and drive the Earth’s system into a state of equilibrium that favors the habitability of the biosphere.”
Most worryingly, researchers found that above a certain critical temperature threshold for the Earth’s atmosphere, a feedback loop could begin where a chaotic outcome would become inevitable. There are some indications that we may have already passed this turning point, but it is not too late to avoid the climate disaster.
Originally published in Live Science.