Atmospheric carbon dioxide has reached a historic threshold as levels remain above 400 parts per million through the end of September – the point in which values typically drop to their lowest.
Climate scientists now warn that it’s ‘almost impossible’ that these numbers will fall next month, and likely won’t dip below 400ppm in the foreseeable future.
While there may be brief, daily events in which the levels fall short of this amount, monthly values are set to keep climbing as the ‘rising half of the cycle’ begins, when carbon dioxide could even break 410 ppm.
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Data from the Mauna Loa Observatory show the recent daily and weekly averages in September have hovered above 400 ppm all month, according to Climate Central.
This value is considered to be a grim tipping point for atmospheric carbon dioxide, with heavy implications for future climate conditions.
While the annual low point in the Mauna Loa CO2 curve typically occurs around the last week of this month, the recent records show the levels have not dipped back down into the 300s.
This low point isn’t consistent each year, and slight variations mean October can occasionally see smaller amounts than September – but, this has only happened four times in the past two decades.
Global warming milestone as scientists warn Earth has passed carbon tipping point | Daily Mail Online