Global CO2 Levels Break Monthly Record

For the first time, average global carbon dioxide (CO2) levels have broken the monthly record, surpassing 400 parts per million (ppm) in March 2015, according to a new NOAA analysis.

"It was only a matter of time that we would average 400 parts per million globally," Pieter Tans, lead scientist of NOAA's Global Greenhouse Gas Reference Network, said in a statement. "We first reported 400 ppm when all of our Arctic sites reached that value in the spring of 2012. In 2013 the record at NOAA's Mauna Loa Observatory first crossed the 400 ppm threshold. 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," he added. "Half of that rise has occurred since 1980."

The NOAA based their estimate on air samples taken from 40 global sites, including the shores of remote islands.

"We choose to sample at these sites because the atmosphere itself serves to average out gas concentrations that are being affected by human and natural forces. At these remote sites we get a better global average," noted Ed Dlugokencky, the NOAA scientist who manages the global network.

The NOAA works with partners around the world to make sustained measurements of atmospheric gases such as greenhouse gases like CO2. These data are used in analyses that help us better understand climate change so we can make informed decisions in the future.

In March, the International Energy Agency reported that the growth of global emissions from fossil fuel burning stalled in 2014, remaining at the same levels as 2013. However, stabilizing the rate of emissions is not enough to avert climate change. NOAA data show that the average growth rate of CO2 concentration in the atmosphere from 2012-2014 was 2.25 ppm per year - the highest ever recorded over three consecutive years. (Scroll to read on...)

Now, last month saw CO2 levels at 400 ppm, and researchers expect the global average to remain above 400 ppm through May, the time of year when global CO2 concentrations peak due to natural cycles on top of the persistent rising greenhouse gases.

Decaying plant matter and soil organisms give off CO2 gas all year long, but the dormant period in plant growth allows the respiration of CO2 to dominate during those months. CO2 levels drop back down as plants begin to bloom, using the greenhouse gas for photosynthesis in late spring and summer.

While these natural processes certainly play a role in climate change, we cannot ignore the fact that human play an extremely large role in the buildup of CO2 in the atmosphere. Some drastic measures will have to be taken, and soon, if we want to curb climate change and prevent its irreversible impacts.

"Elimination of about 80 percent of fossil fuel emissions would essentially stop the rise in carbon dioxide in the atmosphere," added James Butler, director of NOAA's Global Monitoring Division, "but concentrations of carbon dioxide would not start decreasing until even further reductions are made and then it would only do so slowly."

Since we began tracking CO2 in the global atmosphere and realized its harmful effects, officials have been working towards limiting warming to an additional two degrees Celsius (3.6 °F) - known as the Copenhagen Accord. Unfortunately, some have now deemed this climate goal "utterly inadequate."

If we don't figure out a way to reduce the amount of CO2 - and other greenhouse gases, for that matter - that is annually pumped into our atmosphere, we could see many more record-breaking months in our future.

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