The total number and rate increase is accelerating. Wayne Gerdes – CleanMPG – June 10, 2016 The Mauna Loa Observatory (MLO) is an atmospheric research facility that has been continuously monitoring and collecting data related to atmospheric change since the 1950's. The undisturbed air, remote location, and minimal influences of vegetation and human activity at MLO are ideal for monitoring constituents in the atmosphere that can cause climate change. The observatory is part of the National Oceanic and Atmospheric Administration (NOAA) - Earth System Research Laboratory (ESRL) - Global Monitoring Division (GMD). In March, NOAA reported that the annual rate of atmospheric CO2 measured at NOAA’s MLO in Hawaii jumped by 3.05 parts per million during 2015, the largest single year-to-year increase in 56 years of measurement and research. 2015 was also the fourth consecutive year that CO2 grew more than 2 ppm. Pieter Tans, lead scientist of NOAA's Global Greenhouse Gas Reference Network: Levels of the greenhouse gas number and rates of increase were independently measured by NOAA’s Earth System Research Laboratory and by the Scripps Institution of Oceanography. In February 2016, the average global atmospheric CO2 level stood at 402.59 ppm. Prior to 1800, atmospheric CO2 averaged about 280 ppm. The last time the Earth experienced such a sustained CO2 increase was between 17,000 and 11,000 years ago, when CO2 levels increased by 80 ppm. Today’s rate of increase is 200 times faster. The big jump in CO2 is partially due to the current El Niño weather pattern, as forests, plantlife and other terrestrial systems responded to changes in weather, precipitation and drought. The largest previous increase occurred in 1998, also a strong El Niño year. Continued high emissions from fossil fuel consumption are driving the underlying growth rate over the past several years. By all appearances given the slope and normal October lows, global citizens may never again experience < 400 ppm of CO2 concentration ever again. 58 years of Monthly Mean Atmospheric CO2 Mauna Loa Observatory, Hawaii The carbon dioxide data (red curve), measured as the mole fraction in dry air, on Mauna Loa constitute the longest record of direct measurements of CO2 in the atmosphere. They were started by C. David Keeling of the Scripps Institution of Oceanography in March of 1958 at a facility of the National Oceanic and Atmospheric Administration [Keeling, 1976]. NOAA started its own CO2 measurements in May of 1974, and they have run in parallel with those made by Scripps since then [Thoning, 1989]. The black curve represents the seasonally corrected data. Data are reported as a dry mole fraction defined as the number of molecules of carbon dioxide divided by the number of molecules of dry air multiplied by one million (ppm). 1 year of Monthly Mean Atmospheric CO2 Mauna Loa Observatory, Hawaii The above 1-year graph is updated weekly and shows as individual points daily mean CO2 up to and including the week (Sunday through Saturday) previous to today. The daily means are based on hours during which CO2 was likely representative of “background” conditions, defined as times when the measurement is representative of air at mid-altitudes over the Pacific Ocean. That air has had several days time or more to mix, smoothing out most of the CO2 variability encountered elsewhere, making the measurements representative of CO2 over hundreds of km or more. We are beyond the belief stage as this single number and its rate of growth as measured at MLO should be enough to scare anyone concerned about the long term viability of humanity given the fast changes taking place before our very eyes.