The global concentration of carbon dioxide in the atmosphere was measured at 400 parts per million for the first time in recorded history in May of 2013. It was a brief event at the Mauna Loa Observatory in Hawaii at the time. Within the next couple of years, however, readings of at least 400 ppm became standard.
Now, the readings at Mauna Loa have topped 410 parts per million for the month of April. Mauna Loa has been measuring carbon dioxide for 60 years. Back in the 1960s, levels were in the low 300s. Until the 1950s, carbon dioxide levels were in fact relatively stable for hundreds of thousands of years.
Passing 410 ppm so quickly is an ominous and important milestone because it implies that we are likely to reach 450 ppm in the next 16 years and 500 ppm 20 years after that. These numbers are well into the dangerous territory for the stability of the earth’s climate system.
The precipitous rise in level is the direct result of the large release of CO2 from fossil fuel burning. The oceans and plants on land remove a lot of the excess carbon dioxide from the atmosphere, but they simply can’t keep up with the pace at which we are dumping it into the atmosphere.
The Paris Climate Agreement of 2015 represents a world-wide effort to reduce global greenhouse gas emissions. The United States is the only country in the world that is no longer a party to that agreement. Unfortunately for the rest of the world, everyone everywhere will suffer the consequences if we don’t get a handle on this global problem.
Photo, posted July 5, 2008, courtesy of Rick Sharloch via Flickr.