A study by the Texas A&M University, proves that the carbon dioxide concentrations on the earth were for the last 2.5 million years 230 parts per million; Levels today are about 410 parts per million
Humans have never lived under the carbon dioxide-rich atmospheric conditions that have become the norm on Earth in the past sixty years, a new study suggests.
The research findings published in the journal Nature Communications show that low CO2 levels prevailed throughout the Pleistocene period and that during the last 2.5 million years of the Pleistocene period, carbon dioxide concentrations averaged 230 parts per million.
Today's levels are more than 410 parts per million. This study shows that in 1965, atmospheric concentrations of carbon dioxide exceeded 320 parts per million, a high point never reached in the last 2.5 million years.
"According to this study, from the first Homo erectus, which is now dated to 2.1-1.8 million years ago, until 1965, we lived in a low carbon dioxide environment - concentrations were less than 320 parts per million," said Dr. Yi Zhang, author Co-author and Assistant Professor in the Department of Oceanography, College of Geosciences, Texas A&M University.
"Therefore, the current level of carbon dioxide is not only an experiment in the climate and the environment - it is also an experiment for us, for ourselves," he said.
Zhang explained that carbon dioxide is a greenhouse gas that contributes to the warming of the Earth's atmosphere and is considered the cause of global climate change. "It is important to know the concentrations of CO2 in the atmosphere in the geological past, because we know that this already has climatic consequences and will have additional climatic consequences. One way to learn about these consequences is to look at Earth's history," he said. "Then we can see what CO2 levels we had, what the climate looked like and what the relationship between them was."
Jaywei De, Dr. Xiangyang Meng and Dr. Junfeng Ji, from Nanjing University in China; and Dr. Jenner Lee, of the California Institute of Technology, were co-authors of the study.
Ancient Earth Reveals Millions of Years of Data
The scientists analyzed soil samples from the Loess Plain in central China to quantify ancient atmospheric carbon dioxide levels, up to 2.5 million years ago. "Climate scientists often use ice cores as the 'gold standard' of physical climate records," Zhang said, "but ice cores only cover the last 800,000 years."
The researchers reconstructed the Earth's carbon dioxide levels by analyzing soil-forming carbon found in the ancient earth.
"The Loess Plain is an amazing place to look at wind-assisted dust and soil accumulation," Zhang said. "The earliest dust detected in this plane is from 22 million years ago. The layers of loess and the fossilized or ancient soil (paleosol) there contain carbon compounds that record the concentration of atmospheric carbon dioxide, if we look at them carefully."
"Specifically, carbon compounds formed during soil formation usually reach carbon isotopic equilibrium with soil CO2, which is a mixture of atmospheric CO2 and CO2 produced by soil respiration. By applying a two-component mixing model, we can reconstruct ancient levels of CO2 using carbon compounds in fossilized soils," said Jiwei De of Nanjing University.
Reconstructing carbon dioxide history for clues about our future
The researchers used these techniques to construct the history of atmospheric carbon dioxide levels throughout the Pleistocene. "Our reconstructions show that during the entire Pleistocene period, carbon dioxide levels averaged about 230 parts per million, the same as we know for the last 800,000 years," Zhang said.
Dr. Yunfeng Jie of Nanjing University said, "Our estimates of CO2 levels based on ancient soils are consistent with early Pleistocene CO2 levels measured from the ancient blue ice core in Antarctica. This indicates that Earth's ecosystem operated under low CO2 levels throughout the Pleistocene.
"We evolved in a low-carbon environment," Zhang says, "and we need to understand how humans will evolve and be affected by today's carbon dioxide levels."
to the notice of the researchers
More of the topic in Hayadan:
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The reason for this lies in the industrial revolution.
Until then, there were probably changes in the composition of the atmosphere due to large events such as supervolcano eruptions
There are many possible reasons for human extinction such as low reproduction, pollution, nuclear war, Islam, communism, multiculturalism. But carbon dioxide is not one of them, do you see people falling dead in the street because of carbon dioxide in the atmosphere? Mammal species biologically similar to humans did live at higher levels. And if the other reasons don't eliminate us, man always overcomes with the help of technology... just like the false prophets who threatened in the 19th century that the world would starve and then artificial fertilizers appeared. And despite everything, of course, we need to switch to clean energy and without plastic and chemicals because of the pollution.
What good would it do you if man became extinct?
The article is not so clear to me. It shows a total of three pieces of data:
During the Pleistocene the concentration was 230,
In 1965 it reached 320,
Today over 410.
How does the conclusion derive from these data that "until the middle of the twentieth century" we did not live with an atmosphere saturated with carbon dioxide? The Pleistocene period did not end in 1965, but more than 10000 years ago.
What happened from then until 1965?
The title implies that there was a sudden jump in the middle of the 20th century, but from the data it is also possible that there was a gradual increase that began long before that.
I suppose the argument is that the modern lifestyle caused a quick and sudden jump, and maybe that's true, but it would be nice to bring the data on which it's based, because from the research about the Pleistocene period it's impossible to determine that.
Not bad, millions of other species did live and thrive at much higher levels
So then: what is the reason for the rise in temperatures between 1900 and 1940. ?