The concentration of carbon dioxide, the main, long-lived greenhouse gas causing global climate change, in Earth’s atmosphere has reached new heights, according to scientists at Scripps Institution of Oceanography.
Why it matters: The new reading of 415.26 parts per million (ppm) on May 11 was the first daily baseline at Hawaii’s Mauna Loa Observatory to eclipse 415 ppm. That observatory has kept long-term record of carbon dioxide in the atmosphere since 1958. That data, known as the Keeling Curve, traces the continuous increase in the amount of this greenhouse gas in the Earth’s atmosphere since the Industrial Revolution.
- Other observatories around the world also track this increase, which mainly results from burning fossil fuels, deforestation and other human activities. Studies of so-called proxy records detailing the composition of the atmosphere throughout Earth’s history show that carbon dioxide levels are now at their highest point in at least 800,000 — and possibly as many as 3 million — years.
Details: The daily carbon dioxide milestone is largely symbolic, as peaks tend to occur in the Northern Hemisphere each spring. Scientists pay more attention to longer-term trends, rather than the daily data.
- “The average growth rate is remaining on the high end,” says Ralph Keeling, director of Scripps Institution of Oceanography’s CO2 program, via Twitter. Keeling’s father, Charles, began the original CO2 observations in Hawaii.
- “The increase from last year will probably be around three parts per million whereas the recent average has been 2.5 ppm,” Keeling said.
The big picture: Scientists have warned that if the world is to limit global warming to 1.5°C, or 2.7°F, above pre-industrial levels, then sharp emissions cuts have to begin in the next few years, with the world headed for negative emissions — meaning more carbon dioxide is removed by the planet’s oceans, forests and other systems — than is emitted by the end of the century.
- Otherwise Earth will see carbon dioxide concentrations exceeding 450 ppm, which will yield larger increases in global sea levels than we’ve seen so far, along with increasingly severe extreme weather events, such as heat waves and heavy precipitation events.
What’s next: Scientists from Scripps and the National Oceanic and Atmospheric Administration will likely announce a new carbon dioxide monthly record in early June. A new annual figure will come out in early 2020.
CNN | James Griffiths
“We don’t know a planet like this.” That was the reaction of meteorologist Eric Holthaus to news that atmospheric carbon dioxide levels have reached heights not seen in the entirety of human existence — not history, existence. According to data from the Mauna Loa Observatory in Hawaii, the concentration of CO2 in the atmosphere is over 415 parts per million (ppm), far higher than at any point in the last 800,000 years, since before the evolution of homo sapiens. Holthaus spotted the new high on Sunday when it was tweeted out by the Scripps Institution of Oceanography, which measures daily CO2 rates at Mauna Loa along with scientists from the National Oceanic and Atmospheric Administration. Measurements have been ongoing since the program was started in 1958 by the late Charles David Keeling, for whom the Keeling Curve, a graph of increasing CO2 concentration in the atmosphere, is named. “This is the first time in human history our planet’s atmosphere has had more than 415ppm CO2,” Holthaus said in a widely shared tweet. “Not just in recorded history, not just since the invention of agriculture 10,000 years ago. Since before modern humans existed millions of years ago,” added Holthaus. During the Pliocene Epoch, some 3 million years ago, when global temperatures were estimated 2-3 degrees Celsius warmer than today, CO2 levels are believed to have topped out somewhere between 310 to 400 ppm. […] At that time, the Arctic was covered in trees, not ice, and summer temperatures in the far north are believed to have reached around 15C (60F). Global sea levels during the Pliocene were thought to be a whopping 25 meters (82 feet) higher than today, if not higher. High levels of CO2 in the atmosphere — caused by humans burning fossil fuels and cutting down forests — prevent the Earth’s natural cooling cycle from working, trapping heat near the surface and causing global temperatures to rise and rise, with devastating effects. The release of CO2 and other greenhouse gases has already led to a 1C rise in global temperatures, and we are likely locked in for a further rise, if more immediate action is not taken by the world’s governments.
Route Fifty | Bill Lucia
Leaders from places in western states affected by declines in the coal sector met in Denver this week for a workshop organized by the National Association of Counties and National Association of Development Organizations, and funded by the U.S. Economic Development Administration. It’s the latest in a series of events these organizations have put on since 2017 aimed at helping communities that have depended on coal for jobs and government revenues chart a new path. Eleven county and regional teams with participants from Arizona, Colorado, Montana, New Mexico, Utah and Wyoming were slated to take part in this week’s event. Jack Morgan, a community and economic development program manager with NACo who is working on the program, says it’s geared toward “economic resilience, how you can adapt and react and ultimately mitigate economic challenges, economic stress.” But this is not easy. Coal jobs tend to pay well and economies can’t be reinvented overnight. And a place like northern Coconino County, Fowler explains, has added challenges in that it’s remote, and lacks rail lines, nearby interstates and widespread, high-speed internet. Morgan says one theme that has emerged with the work NACo is helping to lead is that small victories are important as places transition away from coal. “We encourage these communities to not necessarily want to hit for home runs immediately,” he said. “To hit for singles.”