PublishedMarch 5, 2021, 8:55 pm
In around a billion years, the earth’s atmosphere could have lost almost all of its oxygen – less than one percent of the 20 percent that remains today. The sun is to blame for this.
- Fee Anabelle Riebeling
Two environmental scientists have calculated how long there will be oxygen on earth.
The bad news: Because of the natural aging of the sun, the days of earthly life are numbered.
The good news: We won’t live to see the end because it won’t be there for around 1 billion years.
We couldn’t exist without oxygen. The air we breathe is so natural for us humans that it would never occur to us that this oxygen might run out one day. But that’s exactly what it will come to.
Like the environmental scientist Kazumi Ozaki from Toho University in Japan and Christopher Reinhard from the Georgia Institute of Technology in the specialist journal «Nature Geoscience» write, of the 21 percent oxygen that is now in the earth’s atmosphere, only one percent will be left in about a billion years.
The older the sun, the more inhospitable it becomes
According to the researchers, the natural aging of the sun and the associated increase in radiation are responsible for the loss of oxygen. At around 4.5 billion years old, it is already emitting a lot of radiation and thus ensuring that plants can carry out photosynthesis.
If this increases, however, the increased irradiation intensifies weathering processes and high temperatures. This in turn changes biogeochemical material cycles and can mean that plants can no longer produce oxygen at some point. Under these conditions, most of today’s life forms could no longer exist.
Relationships are shifting
While oxygen and carbon dioxide decrease sharply, the proportion of methane will increase significantly. “In many respects, the earth’s atmosphere in the distant future will be similar to that of the primordial earth before the so-called Great Oxidation Event”, quoted Scinexx.de Researchers. This event around 2.4 billion years ago enriched the primordial atmosphere, which was previously dominated by methane, nitrogen and carbon dioxide, with oxygen in a short time. The earth would then – viewed from space – more closely resemble the Saturn moon Titan.
After all, according to Ozaki and Reinhard’s prognosis, the earth as we know it won’t run out of air for 1.08 billion years. And not in two to four years, as researchers warned in December (see video above).
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