The Guardian: “The Earth’s climate will enter a new ‘permanent reality’ from next year when concentrations of CO2 in the atmosphere are likely to pass a historic milestone, the head of the UN’s weather agency has warned.”
“The record concentrations of CO2 in the atmosphere were up 43% since pre-industrial times, said the World Meteorological Organization (WMO), prompting its secretary general Michel Jarraud to say immediate action was needed to cut CO2 emissions.”
“Concentrations of CO2 stood at a global annual average of 397.7ppm in 2014, up from about 278ppm in 1750, and the UN said the global annual average is likely to pass the symbolic 400ppm milestone in 2016. Scientists say that the ‘safe’ level of CO2 to avoid dangerous global warming is more like 350ppm.”