Atmospheric CO2 Content On Track To Breach 410 ppm During March - UK Met Office
A never-ending stream of carbon pollution ensures that each year the world continues to break records for carbon dioxide in the atmosphere. This year will be no different.
Like a rite of spring, carbon dioxide is poised to cruise pass the previous mark set last year and reach heights unseen in human history. In the coming weeks, carbon dioxide will start to breach the 410 parts per million threshold on a daily basis at the Mauna Loa Observatory in Hawaii. The monthly average for May could come close to topping 410 ppm, too, according to the U.K. Met Office’s inaugural carbon dioxide forecast, released last week.
Weekly carbon dioxide levels at Mauna Loa Observatory are already nearing last year's peak
Richard Betts, a climate scientist who helped create the forecast, said we should pass last year’s record-setting monthly peak by April or even as soon as this month. It’s not a question of if but rather when depending on wind patterns and other factors that influence daily measurements.
This year’s new high-water mark comes a year after the planet passed the 400 ppm threshold permanently on the back of the greatest yearly rise in carbon dioxide on record. That dramatic rise was driven in part by last year’s super El Niño, but the underlying cause of the steady uptick is human activities that emit carbon pollution.
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If carbon pollution continues on its current trend, it’s likely to pass 450 ppm in the next two decades. That will send temperatures spiraling ever higher and further destabilize the climate.
(Ed. - Given that we first passed the 400 ppm marker back in May of 2013, though only briefly, I would venture that it's going to take a lot less than the "next two decades" to get to 450)
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http://www.climatecentral.org/news/carbon-dioxide-410-ppm-21223