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Heat-trapping Carbon Dioxide in Air Hits Record High
Scientists say the world recently set a record for carbon dioxide in the atmosphere.
The record level was reached although industrial activities that produce carbon dioxide have fallen sharply. That is because of efforts to stop the spread of the new coronavirus.
Carbon dioxide is considered the main human-created greenhouse gas: a heat-trapping gas that warms the Earth's atmosphere.
The National Oceanic and Atmospheric Administration (NOAA) said carbon levels averaged 417.1 parts per million for the month of May. That is 2.4 parts per million higher than a year ago. The measurements were taken at Mauna Loa, a volcano in Hawaii.
Emissions of carbon dioxide, from the burning of fossil fuels, dropped by as much 17 percent in April. Fossil fuels include coal, oil and natural gas. However, the decrease did not last a long time.
Pieter Tans is a lead scientist at NOAA. He said carbon dioxide can stay in the atmosphere for hundreds of years. He added that the short-term reductions of carbon gas for a few months did not have much of a long-term effect.
"It illustrates how difficult it is — what a huge job it is — to bring emissions down," Tans said. "We are really committing the Earth to an enormous amount of warming for a very large time."
Records with direct measurements go back to 1958. Scientists say carbon dioxide levels are now nearly 100 parts per million higher than at that time. That is a 31 percent increase in 62 years.
Jonathan Overpeck is head of the School for Environment and Sustainability at the University of Michigan. He told the Associated Press, "The rise in atmospheric carbon dioxide levels is relentless, and this means the costs of climate change to humans and the planet continue to rise relentlessly as well."
Carbon levels in the air were higher long ago before humans, Tans said.
Tans added that carbon dioxide levels reach their highest in May because growing plants begin using more of the gas. That causes carbon amounts in the air to drop.
I'm Jonathan Evans.
