Until the loss of consciousness, and to start the process of brain damage, the human being can only survive without oxygen for 4 minutes, and death can occur up to 6 minutes later, starting the failure of the biological processes that feed the cells. body cells.
“Oxygen loss is at the very extreme of survival. The human body doesn’t have a huge supply of oxygen, just a few liters, and how you use it depends on your metabolic rate.” BBC Future.
According to Tipton, an adult at rest uses between one-fifth to one-quarter of a liter of oxygen every minute, and this can increase to four liters per minute if they are doing some kind of activity. Panic and stress are contributing factors in increasing the metabolic rate, so for example people cannot survive even the least their bodies can bear without air underwater.
A study published in March 2021 in Nature Geoscience, scientists predicted that in about a billion years, Earth will run out of oxygen, turning the planet into a large ball of barren rock. What will it be like when that happens?
villain and good guy
A 31-page scientific paper by experts at Cornell University, published in the journal astrobiology, revealed that the process of Earth running out of air will be slow and gradual rather than overnight. This is part of its own past, after all, the planet did not have oxygen in the beginning.
After 3.8 billion years, when the surface had cooled enough to become solid, the earliest life emerged just a few million years later. However, the atmosphere was still nothing more than a harmful mixture of gases, such as methane and ammonia, which are now lethal to human life. Science believes that oxygen formed in the oceans as a by-product of cyanobacteria during the process of photosynthesis.
The moment the air was filled with the element, the so-called Great Oxidation Event occurred, a catastrophe that made the air deadly with excess oxygen, leaving a band of rust trapped in the geological record due to overenrichment.
The Sun was responsible for shaping the planet’s atmosphere into what it is today, helping in the process of creating complex life. However, ironically, it is he who could end up killing Earth in the future.
What is going to happen
(Source: New Scientist/Reproduction)
Before the Sun enters its final stages of life, turning into a huge red star that will devour Mercury and Venus before charring everything in its path, Earth will already have been destroyed by its heat.
Julianna Sackmann and Kathleen Kraemer of the University of Toronto Institute of Technology showed in their study indicated by the New Scientist, which since the Sun lit up 4.5 billion years ago, has become 30% brighter. In the next billions of years, it should brighten by another 10%, which will be too much for our planet, which could face the same smoldering, arid, suffocating fate as Venus.
Oxygen will begin to be affected by the Sun due to rocks, responsible for regulating the environment through the carbonate-silicate cycle, switching between the atmosphere and carbonate minerals. This will be interrupted by high levels of sunlight, which will cause the planet’s rocks to absorb more COtwo than they return.
Although very slowly, as more carbon dioxide is trapped in the rocks, the Earth’s atmosphere will have less for plants to photosynthesize, resulting in a catastrophic drop in the world’s oxygen levels. This will be the beginning of the end for forests, which will die from excess light, creating a desert of branches on the planet’s surface.
The oceans will be the only ones that will sustain the photosynthesis process for a longer time, however, they will be no match for the heat of the sun’s rays. As such, they will enter a state known as a “wet greenhouse”, a climate effect of evaporation considered a death sentence for a planet.
There is a long debate of differing ideas whether humanity will last long enough to watch the planet die. We would have to survive a thousand times longer for that, and by then it will be 300,000 years on Earth.
However, even if that happens, the civilization of the moment will certainly already have enough resources and intelligence to move to some other corner of the Solar System or beyond.