Methane emitted by humans is very underestimated, Methane is a strong greenhouse gas and contributes to global warming.
Methane emissions to the atmosphere have increased by about 150 percent in the last three centuries, but it is difficult for researchers to determine where these emissions come from. Gases that store heat such as methane can be released both naturally and through human activities. Methane emitted by humans is very underestimated.
Researchers at the University of Rochester Benjamin Hmiel, a doctoral student in Vasily Petrenko’s laboratory, professor of earth and environmental sciences, and their staff measured the methane content in old air samples and found that scientists significantly underestimated the amount of methane in humans due to fossil fuels in the atmosphere . issued. Methane emitted by humans is very underestimated.
Stricter regulations on methane emissions from fossil fuel production could reduce future global warming more than previously thought, researchers said.
Methane is the second largest anthropogenic origin that arises from human activities that contribute to global warming after carbon dioxide. However, like other gases that trap heat, methane has a relatively short shelf life compared to carbon dioxide. it lasts an average of only nine years in the atmosphere, while carbon dioxide can remain in the atmosphere for about a century, for example. Methane emitted by humans is very underestimated.
This makes methane a very suitable target for limiting emissions in the short term.
If we stop removing all carbon dioxide today, there will be high levels of carbon dioxide in the atmosphere for a long time in the future, the researchers say.
Methane is important to study because if we make changes to our current methane emissions, it will have a faster impact.
Methane emitted into the atmosphere can be divided into two categories based on the signature of carbon 14, a rare radioactive isotope. There are methane fossils that have been bound to old hydrocarbon deposits for millions of years and no longer contain carbon-14 because their isotopes decay. and has biological methane that is in contact with plants and wildlife on the surface of the planet and contains carbon-14. Methane emitted by humans is very underestimated.
Organic methane can be released naturally from sources such as wetlands or from anthropogenic sources such as landfills, rice fields and livestock.
Fossil methane at the heart of Hmiel’s exploration can be obtained through natural geological breakthroughs or through the extraction and use of fossil fuels such as oil, gas, and coal.
Scientists can accurately determine the total amount of methane released into the atmosphere each year, but it is difficult to divide this volume into its individual components.
As a scientific community, we struggle to understand exactly how much methane we release into the atmosphere as humans, said the study’s co-authors. We know that the fossil fuel component is one of our biggest component emissions, but it is a challenge to determine that the natural and anthropogenic components of fossil emissions look the same as isotopes in the atmosphere today. Methane emitted by humans is very underestimated.
To more precisely separate natural and anthropogenic components, Hmiel and his colleagues turned to the past and drilled and collected ice cores from Greenland.
Ice core samples act as time capsules: they contain air bubbles in which small amounts of old air are trapped.
The researchers used the melting chamber to extract old air from bubbles and then examine their chemical composition.
Hmiel’s research focuses on measuring the composition of the air from the beginning of the 18th century before the industrial revolution began to the present. Only in the mid-19th century did humans begin to use fossil fuels in sufficient quantities.
By measuring emissions before this period, researchers can identify natural emissions that are not present in fossil fuels in the atmosphere today.
There is no evidence that natural fossil methane emissions can fluctuate for several centuries.
When measuring carbon 14 isotopes in the air more than 200 years ago, the researchers found that almost all of the methane emitted into the atmosphere was biological until around 1870. At this point, the fossil component began to rise rapidly. The time coincides with a sharp increase in the use of fossil fuels.
The level of naturally released fossil methane is about ten times lower than in previous studies.
Given the total fossil emissions measured in the atmosphere today, Hmiel and his colleagues concluded that the artificial fossil component was 25 to 40 percent higher than predicted.
Important data for climate research: if anthropogenic methane emissions contribute more than total emissions, reducing human emissions from extraction and use of fossil fuels will have a greater impact on curbing global warming in the future than scientists had previously predicted. This is actually good news for Hmiel. Methane emitted by humans is very underestimated.
Researchers say that I don’t want to be too desperate about this because my data have a positive effect: most of the methane emissions are anthropogenic, so we have more control. If we can reduce our emissions, it will have a greater impact.