CO2 Levels Top 415 PPM for First Time in Human History
The human species experienced an alarming milestone this weekend: for the first time since Homo sapiens evolved, atmospheric carbon dioxide levels surpassed 415 parts per million (ppm), CNN reported.
The carbon dioxide high was recorded by the Mauna Loa Observatory in Hawaii and tweeted out by the Scripps Institution of Oceanography Saturday, which regularly updates C02 levels. The observatory recorded a daily C02 reading of 415.26 ppm, which is the first time the daily level topped 415 ppm.
Meteorologist and climate action advocate Eric Holthaus sounded the alarm about that data point in widely-shared retweet.
"We don't know a planet like this," he said.
This is the first time in human history our planet's atmosphere has had more than 415ppm CO2. Not just in recorded… https://t.co/C2I6k2XFXz— Eric Holthaus (@Eric Holthaus)1557695247.0
Carbon dioxide levels did not top 300 ppm in the 800,000 years before the industrial revolution, according to USA Today. A study in April used computer models to confirm that carbon dioxide levels today are the highest they have been in three million years. The study also showed that current levels would be at around 280 ppm if it weren't for the burning of fossil fuels by human beings, leading to climate change.
The last time carbon dioxide levels were this high was 5.3 to 2.6 million years ago during the Pliocene epoch, when beech trees grew in Antarctica, temperatures were three to four degrees Celsius warmer and sea levels were 20 meters (approximately 65.6 feet) higher.
Holthaus wasn't the only one to respond to Saturday's news with alarm.
"Thinking about Mother Nature today," 350.org Founder Bill McKibben tweeted.
Thinking about Mother Nature today. As of this morning, her CO2 concentration topped 415 ppm for the first time in… https://t.co/Dr1m6jLBlh— Bill McKibben (@Bill McKibben)1557696617.0
The C02 levels recorded at the Mauna Loa observatory reached 410 ppm for the first time in May of 2018, USA Today reported. Charles David Keeling took the first reading at the volcanic observatory in 1958, and his son Ralph Keeling has continued the work following his father's death. The so-called Keeling Curve documents the rise in carbon dioxide over the last 61 years, upwards from an initial reading of 313 ppm in March of 1958, according to The Independent.
"The average growth rate is remaining on the high end," Keeling, who directs the Scripps CO2 program, said in a statement reported by The Independent. "The increase from last year will probably be around three parts per million whereas the recent average has been 2.5 ppm. "[It's] likely we're seeing the effect of mild El Niño conditions on top of ongoing fossil fuel use."
Energy-related carbon dioxide emissions reached a record high in 2018 of 33.1 gigatons (Gt) of the greenhouse gas, up 1.7 percent from the year before, according to the most recent calculations from the International Energy Agency.