WMO - Every Northern Hemisphere Station Reported 400+ PPM CO2 For Entire Month Of April
A new carbon dioxide milestone has been reached according to the World Meteorological Agency. Average carbon dioxide measurements at all monitoring stations in the northern hemisphere were above 400 parts per million for the month of April, the first time that’s been recorded in human history.
Previous reports from the Mauna Loa Observatory, the longest continually running CO2 monitoring site in the world, showed that the average CO2 concentration for April was above 400 ppm. On Monday, the WMO reported that the 11 other northern hemisphere monitoring stations that continuously monitor CO2 also surpassed the 400 ppm mark for the month.
“This should serve as yet another wake-up call about the constantly rising levels of greenhouse gases, which are driving climate change. If we are to preserve our planet for future generations, we need urgent action to curb new emissions of these heat trapping gases,” WMO Secretary-General Michel Jarraud said in a press release.
Atmospheric CO2 levels follow a seasonal pattern in the northern hemisphere, rising throughout the winter and peaking in late spring when blooming plants start to suck CO2 out of the air. Monitoring stations closer to the equator, where there’s less seasonality, and in the southern hemisphere, where there’s less land, don’t show the same dramatic fluctuations throughout the year.
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http://www.climatecentral.org/news/co2-400-ppm-global-17485