The Geographic South Pole hits alarming climate change milestone
20 June 2016 | Mitigation
Soon after New Zealand passed a worrying climate change milestone, scientists have confirmed that atmospheric carbon dioxide levels have now also hit 400 parts per million (PPM) in Antarctica.
The South Pole was the last place on Earth to cross the mark - an amount not seen there for four million years and a grim symbol of the swift pace at which man-made pollution is warming the world.
The pole has shown the same, relentless upward trend in CO2 as the rest of world, but its remote location means it's the last to register the impacts of increasing emissions from fossil fuel consumption, the primary driver of greenhouse gas pollution.
The level was recorded for the first time in New Zealand just a few weeks ago at NIWA's Clean Air Monitoring Station at Baring Head, and in Australia shortly before in Cape Grim, Tasmania.
"The far Southern Hemisphere was the last place on earth where CO2 had not yet reached this mark," said Pieter Tans, the lead scientist of the National Oceanic and Atmospheric Administration (NOAA) Global Greenhouse Gas Reference Network.
"Global CO2 levels will not return to values below 400 ppm in our lifetimes, and almost certainly for much longer."
Over the course of the year, CO2 levels rise during fall and winter and decline during the Northern Hemisphere's summer as terrestrial plants consume CO2 during photosynthesis.
But plants only capture a fraction of annual CO2 emissions, so for every year since observations began in 1958, there has been more CO2 in the atmosphere than the year before.
Last year's global CO2 average reached 399 ppm, meaning that the global average in 2016 will almost certainly surpass 400 ppm.
The only question was whether the lowest month for 2016 will also remain above 400 ppm.
The annual rate of increase also appeared to be accelerating.
SOURCE: NZ Herald