Image credit: Shutterstock / Maxim Kulko
NOAA scientists reported today that global levels of carbon dioxide (CO2), the most prevalent heat-trapping gas in the atmosphere, have passed a significant milestone.
NOAA says in March, 2015, the global monthly average for carbon dioxide concentration surpassed 400 parts per million. That’s the first month in modern records that the entire globe broke 400 ppm, reaching levels that haven’t been seen in about 2 million years.
Pieter Tans is lead scientist of NOAA’s Global Greenhouse Gas Reference Network. Tans said:
It was only a matter of time that we would average 400 parts per million globally.
He said that C02 had passed the 400 ppm level for the first time in the Arctic in the spring of 2012, and at Mauna Loa in Hawaii in 2013. Tans said:
Reaching 400 parts per million as a global average is a significant milestone.
This marks the fact that humans burning fossil fuels have caused global carbon dioxide concentrations to rise more than 120 parts per million since pre-industrial times. Half of that rise has occurred since 1980.
Carbon dioxide is a natural part of Earth’s atmosphere but the burning of fossil fuels sends excess amounts into the air and traps more of the sun’s heat.
Image credit: NOAA
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The International Energy Agency reported on March 13 that the growth of global emissions from fossil fuel burning stalled in 2014, remaining at the same levels as 2013. Stabilizing the rate of emissions is not enough to avert climate change, however. NOAA data show that the average growth rate of carbon dioxide concentration in the atmosphere from 2012 to 2014 was 2.25 ppm per year, the highest ever recorded over three consecutive years.
NOAA bases the global carbon dioxide concentration on air samples taken from 40 global sites. NOAA and partner scientists collect air samples in flasks while standing on cargo ship decks, on the shores of remote islands and at other locations around the world. It takes some time after each month’s end to compute this global average because samples are shipped from locations for analysis at NOAA’s Earth System Research Laboratory in Boulder, Colorado.
Ed Dlugokencky, the NOAA scientist who manages the global network, said he expects the global average will remain above 400 ppm through May, the time of year when global carbon dioxide concentrations peak due to natural cycles on top of the persistent rising greenhouse gases. Decaying plant matter and soil organisms give off carbon dioxide gas all year long, but the dormant period in plant growth allows the respiration of carbon dioxide to dominate during those months. Carbon dioxide levels drop back down as plants begin to bloom, using carbon dioxide for photosynthesis in late spring and summer.
James Butler, director of NOAA’s Global Monitoring Division, added that it would be difficult to reverse the increases of greenhouse gases which are driving increased atmospheric temperatures. He said:
Elimination of about 80 percent of fossil fuel emissions would essentially stop the rise in carbon dioxide in the atmosphere, but concentrations of carbon dioxide would not start decreasing until even further reductions are made and then it would only do so slowly.
Bottom line: NOAA scientists report that in March, 2015, the global monthly average for carbon dioxide concentration surpassed 400 parts per million. That’s the first month in modern records that the entire globe broke 400 ppm, reaching levels that haven’t been seen in about 2 million years.
from EarthSky http://ift.tt/1IP51Cq
Image credit: Shutterstock / Maxim Kulko
NOAA scientists reported today that global levels of carbon dioxide (CO2), the most prevalent heat-trapping gas in the atmosphere, have passed a significant milestone.
NOAA says in March, 2015, the global monthly average for carbon dioxide concentration surpassed 400 parts per million. That’s the first month in modern records that the entire globe broke 400 ppm, reaching levels that haven’t been seen in about 2 million years.
Pieter Tans is lead scientist of NOAA’s Global Greenhouse Gas Reference Network. Tans said:
It was only a matter of time that we would average 400 parts per million globally.
He said that C02 had passed the 400 ppm level for the first time in the Arctic in the spring of 2012, and at Mauna Loa in Hawaii in 2013. Tans said:
Reaching 400 parts per million as a global average is a significant milestone.
This marks the fact that humans burning fossil fuels have caused global carbon dioxide concentrations to rise more than 120 parts per million since pre-industrial times. Half of that rise has occurred since 1980.
Carbon dioxide is a natural part of Earth’s atmosphere but the burning of fossil fuels sends excess amounts into the air and traps more of the sun’s heat.
Image credit: NOAA
Enjoying EarthSky so far? Sign up for our free daily newsletter today!
The International Energy Agency reported on March 13 that the growth of global emissions from fossil fuel burning stalled in 2014, remaining at the same levels as 2013. Stabilizing the rate of emissions is not enough to avert climate change, however. NOAA data show that the average growth rate of carbon dioxide concentration in the atmosphere from 2012 to 2014 was 2.25 ppm per year, the highest ever recorded over three consecutive years.
NOAA bases the global carbon dioxide concentration on air samples taken from 40 global sites. NOAA and partner scientists collect air samples in flasks while standing on cargo ship decks, on the shores of remote islands and at other locations around the world. It takes some time after each month’s end to compute this global average because samples are shipped from locations for analysis at NOAA’s Earth System Research Laboratory in Boulder, Colorado.
Ed Dlugokencky, the NOAA scientist who manages the global network, said he expects the global average will remain above 400 ppm through May, the time of year when global carbon dioxide concentrations peak due to natural cycles on top of the persistent rising greenhouse gases. Decaying plant matter and soil organisms give off carbon dioxide gas all year long, but the dormant period in plant growth allows the respiration of carbon dioxide to dominate during those months. Carbon dioxide levels drop back down as plants begin to bloom, using carbon dioxide for photosynthesis in late spring and summer.
James Butler, director of NOAA’s Global Monitoring Division, added that it would be difficult to reverse the increases of greenhouse gases which are driving increased atmospheric temperatures. He said:
Elimination of about 80 percent of fossil fuel emissions would essentially stop the rise in carbon dioxide in the atmosphere, but concentrations of carbon dioxide would not start decreasing until even further reductions are made and then it would only do so slowly.
Bottom line: NOAA scientists report that in March, 2015, the global monthly average for carbon dioxide concentration surpassed 400 parts per million. That’s the first month in modern records that the entire globe broke 400 ppm, reaching levels that haven’t been seen in about 2 million years.
from EarthSky http://ift.tt/1IP51Cq
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