Growth of CO₂ in the atmosphere is accelerating. The image shows the growth rate in parts per million (ppm), based on annual Mauna Loa data (1959-2017), with a 4th-order polynomial trend added.
While no data are yet available for the year 2018, the trend on above image points at 2.65 ppm. The image below shows the level for the most recent week, which is 2.53 ppm above the corresponding week a year ago.
Carl Rasmussen calculates that the de-seasonalised growth rate has now (at the middle of 2018) reached ±2.3 ppm/y. Carl adds: “the rate of growth is itself growing, [it is] the highest growth rate ever seen in modern times. This is not just a ‘business as usual’ scenario, it is worse than that, we’re actually moving backward, becoming more and more unsustainable with every year. This shows unequivocally that the efforts undertaken so-far to limit green house gases such as carbon dioxide are woefully inadequate.”
Peak methane levels were as high as 3.37 ppm on August 31, 2018, an ominous warning of the threat of destabilization of methane hydrates at the seafloor of the Arctic Ocean.
Mean global methane levels were as high as