The Star Beacon; Ashtabula, Ohio

World, nation, state

May 11, 2013

CO2 level reaches amount never encountered by humans

WASHINGTON — Worldwide levels of the chief greenhouse gas that causes global warming have hit a milestone, reaching an amount never before encountered by humans, federal scientists said Friday.

Carbon dioxide was measured at 400 parts per million at the oldest monitoring station which is in Hawaii sets the global benchmark. The last time the worldwide carbon level was probably that high was about 2 million years ago, said Pieter Tans of the National Oceanic and Atmospheric Administration.

That was during the Pleistocene Era. “It was much warmer than it is today,” Tans said. “There were forests in Greenland. Sea level was higher, between 10 and 20 meters (33 to 66 feet).”  

Other scientists say it may have been 10 million years ago that Earth last encountered this much carbon dioxide in the atmosphere. The first modern humans only appeared in Africa about 200,000 years ago.

The measurement was recorded Thursday and it is only a daily figure, the monthly and yearly average will be smaller. The number 400 has been anticipated by climate scientists and environmental activists for years as a notable indicator, in part because it’s a round number — not because any changes in man-made global warming happen by reaching it.

“Physically, we are no worse off at 400 ppm than we were at 399 ppm,” Princeton University climate scientist Michael Oppenheimer said. “But as a symbol of the painfully slow pace of measures to avoid a dangerous level of warming, it’s somewhat unnerving.”

Environmental activists, such as former Vice President Al Gore, seized on the milestone.

“This number is a reminder that for the last 150 years — and especially over the last several decades — we have been recklessly polluting the protective sheath of atmosphere that surrounds the Earth and protects the conditions that have fostered the flourishing of our civilization,” Gore said in a statement. “We are altering the composition of our atmosphere at an unprecedented rate.”

Carbon dioxide traps heat just like in a greenhouse and most of it stays in the air for a century; some lasts for thousands of years, scientists say. It accounts for three-quarters of the planet’s heat-trapping gases. There are others, such as methane, which has a shorter life span but traps heat more effectively. Both trigger temperatures to rise over time, scientists say, which is causing sea levels to rise and some weather patterns to change.

When measurements of carbon dioxide were first taken in 1958, it measured 315 parts per million. Some scientists and environmental groups promote 350 parts per million as a safe level for CO2, but scientists acknowledge they don’t really know what levels would stop the effects of global warming.

The level of carbon dioxide in the air is rising faster than in the past decades, despite international efforts by developed nations to curb it. On average the amount is growing by about 2 parts per million per year. That’s 100 times faster than at the end of the Ice Age.

Back then, it took 7,000 years for carbon dioxide to reach 80 parts per million, Tans said. Because of the burning of fossil fuels, such as oil and coal, carbon dioxide levels have gone up by that amount in just 55 years.

Before the Industrial Revolution, carbon dioxide levels were around 280 ppm, and they were closer to 200 during the Ice Age, which is when sea levels shrank and polar places went from green to icy. There are natural ups and downs of this greenhouse gas, which comes from volcanoes and decomposing plants and animals. But that’s not what has driven current levels so high, Tans said. He said the amount should be even higher, but the world’s oceans are absorbing quite a bit, keeping it out of the air.

“What we see today is 100 percent due to human activity,” said Tans, a NOAA senior scientist. The burning of fossil fuels, such as coal for electricity and oil for gasoline, has caused the overwhelming bulk of the man-made increase in carbon in the air, scientists say.

The world pumps on average 2.4 million pounds of carbon dioxide into the air every second for a total of 38.2 billion tons in 2011, according international calculations published in a scientific journal in December. China spews 10 billion tons of carbon dioxide into the air per year, leading all countries, and its emissions are growing about 10 percent annually. The U.S. at No. 2 is slowly cutting emissions and is down to 5.9 billion tons per year.

The speed of the change is the big worry, said Pennsylvania State University climate scientist Michael Mann. If carbon dioxide levels go up 100 parts per million over thousands or millions of years, plants and animals can adapt. But that can’t be done at the speed it is now happening.

Last year, regional monitors briefly hit 400 ppm in the Arctic. But those monitoring stations aren’t seen as a world mark like the one at Mauna Loa, Hawaii.

Generally carbon levels peak in May then fall slightly, so the yearly average is usually a few parts per million lower than May levels.

1
Text Only
World, nation, state
  • Woman, teenager found dead in Lake Erie; 2 missing

    The bodies of two of four missing boaters were recovered in western Lake Erie on Thursday, a day after the group left for an afternoon of fishing and sent pictures to relatives.

    April 18, 2014

  • Astronomers spot most Earth-like planet yet

    Astronomers have discovered what they say is the most Earth-like planet yet detected — a distant, rocky world that’s similar in size to our own and exists in the Goldilocks zone where it’s not too hot and not too cold for life.
     

    April 18, 2014

  • Lordstown eyes fall rollout of updated Cruze

    Production of the updated Chevrolet Cruze is tentatively set to begin early this fall at the General Motors facility in Lordstown, a plant official confirmed.
     

    April 17, 2014

  • A year after background check defeat, modest goals

    Democratic worries about this November’s elections, a lack of Senate votes and House opposition are forcing congressional gun-control supporters to significantly winnow their 2014 agenda, a year after lawmakers scuttled President Barack Obama’s effort to pass new curbs on firearms.
     

    April 17, 2014

  • College Board provides a glimpse of new SAT

    Anxious students — not to mention their parents — can get a heads-up for how the redesigned SAT might look in two years.
     

    April 17, 2014

  • Screen Shot 2014-04-16 at 12.51.22 PM.png VIDEO: Toddler climbs into vending machine

    A child is safe after climbing into and getting stuck inside a claw crane machine at a Lincoln, Neb., bowling alley Monday.

    April 16, 2014 1 Photo

  • Poll finds Clinton trouncing entire GOP field

    Hillary Clinton isn’t only the strong front-runner for the 2016 Democratic presidential nomination, but she’s well ahead of every potential Republican rival, according to a new McClatchy-Marist Poll.
     

    April 16, 2014

  • Ukraine bares teeth against eastern uprising

    In the first Ukrainian military action against a pro-Russian uprising in the east, government forces repelled an attack Tuesday by about 30 gunmen at an airport, beginning what the president called an “anti-terrorist operation” to try to restore authority over the restive region.
     

    April 16, 2014

  • U.N. Security Council sees grim images of Syrian dead

    The U.N. Security Council fell silent Tuesday after ambassadors viewed a series of ghastly photographs of dead Syrian civil war victims, France’s ambassador said. The pictures showed people who were emaciated, with their bones protruding, and some bearing the marks of strangulation and repeated beatings, and eyes having been gouged out.

    April 16, 2014

  • U.S.: Russia causing Ukraine unrest

    The White House on Monday said there was “overwhelming evidence” that Russia is fomenting unrest in eastern Ukraine, but suggested that President Barack Obama has not yet concluded that Vladimir Putin’s actions warrant broader sanctions on key Russian economic sectors.

    April 15, 2014

House Ads
Parade
Magazine

Click HERE to read all your Parade favorites including Hollywood Wire, Celebrity interviews and photo galleries, Food recipes and cooking tips, Games and lots more.
AP Video