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There is more planet-warming CO2 in the atmosphere than at any point in 4 million years



“Fossil-fuel use may no longer be accelerating, but we are still racing at top speed towards a global catastrophe."


That's the stark assessment from Ralph Keeling, a geochemist who heads data collection for the National Oceanic and Atmospheric Administration through its collaboration with the Scripps Institution of Oceanography at the University of California San Diego announced today.


Carbon dioxide measured at the Mauna Loa Atmospheric Baseline Observatory peaked at 421 million parts per million last month.


It's the highest amount recorded to date and the largest concentration of planet-warming gases seen at any point in the last 4 million years.


For reference, 4 million years ago was when the Australopithecus species that provides the evolutionary link between humans and other primates began walking the Earth. It also marked a period when there was no sea ice in the Arctic Circle in the summer.


“The science is irrefutable: humans are altering our climate in ways that our economy and our infrastructure must adapt to,” said NOAA Administrator Rick Spinrad, Ph.D. “We can see the impacts of climate change around us every day. The relentless increase of carbon dioxide measured at Mauna Loa is a stark reminder that we need to take urgent, serious steps to become a more Climate Ready Nation.”


Carbon dioxide pollution from burning fossil fuels for transportation, electricity generation, cement manufacturing, deforestation, and agriculture is the leading cause of global warming.

When these gases are released into the atmosphere they trap heat from the planet's surface that would otherwise be released into space. Those heat trapping gases are causing the atmosphere to warm, which causes extreme weather conditions like heatwaves, drought, wildfires, floods, and severe storms like hurricanes and typhoons.


Meanwhile, greenhouse gas pollution also warms oceans, makes them more acidic and threatens all sorts of marine life.


Since the industrial revolution, humans have thrown up an estimated 1.5 trillion tons of CO2 pollution, according to the NOAA, much of which will continue to warm the atmosphere for thousands of years.


Monitoring the carbon dioxide in the air is something of a family affair for Keeling, whose father -- Charles David Keeling -- began tracking CO2 in the atmosphere at Mauna Loa back in 1958 for the Scripps Institution.


The senior Keeling was the first to recognize that CO2 levels in the Northern Hemisphere fell during the growing season, and rose as plants died back in the fall, and he documented these CO2 fluctuations in a record that came to be known as the Keeling Curve, according to the NOAA. He was also the first to recognize that, despite the seasonal fluctuation, CO2 levels were rising every year.


“It's depressing that we've lacked the collective will power to slow the relentless rise in CO2,” said the younger Keeling.


Technology and tools exist to reverse course on global warming, but it will require massive policy shifts.


“Carbon dioxide is at levels our species has never experienced before - this is not new,” said Pieter Tans, senior scientist with the Global Monitoring Laboratory. “We have known about this for half a century, and have failed to do anything meaningful about it. What's it going to take for us to wake up?"

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