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Global monthly average of carbon dioxide hits 400 ppm milestone

Despite scientist warnings, the global community continues to degrade the biosphere by overloading it with greenhouse gases from burning of coal, oil, and gas. The latest historic milestone is that the global monthly average level for carbon dioxide reached 400.83 parts per million in March 2015. This is the first time that the worldwide average has surpassed 400 parts per million in about 2 million years.

The National Oceanic and Atmospheric Administration announced the record high. Chief greenhouse gas scientist Pieter Tans said that this new record is “daunting from the standpoint on how hard it is to slow this down.” He noted that the pace at which carbon dioxide is increasing is 100 times faster than natural rises in the past. Since NOAA first calculated the global carbon dioxide average 35 years ago, the average has risen 61 parts per million. In prehuman times it took about 6000 years for carbon dioxide to rise about 80 parts per million.

In 2013, the World Meteorological Organization issued a report labeling the 400 parts per million threshold as the level at which more dramatic climactic impacts become likely. At that time the global average level of atmospheric carbon was just under 400 parts per million. Princeton University professor of geosciences Michael Oppenheimer said that 400 parts per million is the “level that climate scientists have identified as the beginning of the danger zone.”

Read the 2013 Global Greenhouse Gas Report by the World Meteorological Organization here.