Atmospheric carbon dioxide levels hit 410 parts per million (ppm) last week for the first time in recorded history, a level the planet has not seen in three million years, according to measurements taken at the Mauna Loa Observatory in Hawaii.
“Since measurements began in the 1950s at Mauna Loa, atmospheric concentrations of carbon dioxide have increased 42% increase from pre-industrial levels,” ThinkProgress reports. “Children born today will likely never live in a world with levels below 400 parts per million,” since the carbon dioxide now in the atmosphere will persist for decades.
The last time atmospheric CO2 reached this threshold, in the mid-Pliocene, “global average temperature was about 3.6 to 5.2°F (2.0 to 3.0°C) warmer than it is today,” writes correspondent Natasha Geiling. “Sea levels were also higher, by about 15 to 25 metres.”
Geiling notes that the Mauna Loa facility, jointly funded by the U.S. National Oceanic and Atmospheric Administration (NOAA) and the Scripps Institute of Oceanography, may be vulnerable to budget cuts at the hands of the Trump administration. Office of Management and Budget Director Mick Mulvaney considers climate spending “to be a waste of your money.”
On the National Observer, climate analyst and writer Barry Saxifrage notes that the increase in atmospheric CO2 continues to accelerate, according to a NOAA release last month. The agency pointed to an “unprecedented” increase over the last two years, cited 2016 as “a record fifth consecutive year that carbon dioxide (CO2) rose by 2 ppm or greater”, and noted that those five years showed an average 2.5 ppm annual increase for the first time. That’s despite International Energy Agency reports indicating that fossil CO2 emissions have plateaued, notwithstanding continuing economic growth.
Saxifrage points to four possible disconnects between the IEA data and the realities in the NOAA report: The conclusion that emissions have plateaued may be based on inadequate verification of inaccurate national data, emissions may be rising in other areas of human activity, climate change itself might be driving up emissions, and the oceans and biosphere might be absorbing less CO2.
Whatever the cause, the NOAA report “is just the latest to show that the path to a safe climate future requires rapid reductions in how much CO2 we pull out of the ground each year,” Saxifrage writes. “Canada, however, is planning to do the very opposite.” The country’s CO2 emissions have increased 50% since 1990, and its oil and gas emissions have doubled. And he cites Oil Change International’s conclusion that, “over the next 20 years, the industry is set to expand oil production by more in Canada than in any other country. If it continues on this course, Canada could become one of the world’s largest extractors of the new carbon that would drive the atmosphere over the edge.”
