Why was Earth able to maintain a relatively stable climate over billions of years while conditions on Venus and Mars deteriorated rapidly? If we know that some key chemical cycles underlie this massive climate self-regulating mechanism that enabled the evolution of complex life, the interactions and cause-and-effect relationships that connect them are still poorly understood. A new study offers a new math-based approach that could help make things clearer.
Although the environmental conditions of the early Earth 4 billion years ago are thought to have been very different from those we know today, they were stable and favorable enough to allow life to arise and develop.
With the emergence of the first continents and the beginning of modern plate tectonics, certain geochemical cycles were established that allowed the Earth's climate to remain surprisingly stable over millions of years. It is certain that the Earth has witnessed multiple episodes of… GlaciationGlaciation Or the temperature rises intensely at times. Temperature and humidity conditions remained variable, but each time they remained within an acceptable range for living organisms, or at least for some. Because although more extreme climate events may have led to mass extinctions, the situation never deteriorated to the point of completely eliminating life on Earth. Likewise, despite these marked climatic fluctuations, the Earth's climate has always managed to regulate itself quickly enough to avoid irreversible runaways.
Two sister planets to Earth have failed to regulate their climate
Although this may seem trivial to us, it is clear that our neighbor Mars and VenusVenusAnd he did not take the same path. Everything, or almost everything, seems to be destined for these three sister planets to have a suitable environment for life. Several witnesses told us that an outside observer could have seen three Blue planetsBlue planets At the beginning Solar systemSolar system. Today, only Earth can boast this designation. This peculiarity tells us that despite a relatively similar beginning to Earth, Mars and Venus did not have the means to develop regulatory mechanisms that would allow stable climatic conditions to be maintained over time. For Venus, things certainly deteriorated very quickly, turning this world, although very similar to Earth, into an uninhabitable furnace. Clearly, Mars would have resisted for much longer before the climate shifted permanently toward complete aridity.
Should land then be considered an exception? A crucial question for the search for extraterrestrial life on others ExoplanetsExoplanets. But to answer this question, it is necessary to understand the mechanisms that have been involved in regulating this climate for many billions of years. However, things are far from simple.
A complex puzzle of the complex biogeochemical cycles that govern Earth's climate
We know that the geochemical cycles that occur between the oceans, atmosphere, and rocks are essential, but the mechanisms are so complex that it is difficult to study climate regulation as a whole. Therefore, researchers are often forced to study each piece of this giant puzzle independently. However, it is the interactions between these different cycles that also help explain how Earth has managed to maintain habitable conditions for so long.
Therefore, the researchers decided to look at the problem from another angle. Instead of diving into the details of each mechanism, scientists chose to highlight the relationships between different chemical cycles from a broad and highly simplified point of view, using mathematical tools. The results have been published In the magazine With people.
A global diagram for identifying interactions between different chemical cycles
This new approach makes it possible to identify the foundations of Earth's climate stability. This mathematical analysis allows the identification of multiple groups of Chemical reactionsChemical reactions Primary or secondary, which allows the regulation of the carbon cycle, as well as the interactions between these groups. Thus, the Earth's climate can be represented by a set of:Chemical equationsChemical equations Interconnected, which play out systematically.
Based on this diagram, it becomes possible to create a sequence of reactions. ” If the process “Preston Kemeny, first author of the study, explains, In a press release from the University of Chicago. In other words, these conceptual mathematical results make it possible to make theoretical predictions about the sequence of processes associated with climate regulation. Interesting results for understanding the future evolution of climate in the face Global WarmingGlobal Warming current.
