NOAA's Global Monitoring Laboratory posts an Annual Greenhouse Gas Index (AGGI) that tracks yearly changes in the warming-influence of long-lived, trace greenhouse gases.  

As reported May 14, 2020, by NOAA-ESRL with an update to its AGGI webpage, the combined influence of all greenhouse gases in the Earth's atmosphere reached the equivalent of 500 ppm CO2 in 2019.  With carbon dioxide and other GHGs continuing to accumulate in the atmosphere, despite the global COVID-19 pandemic, humanity's climate crisis has now surpassed the symbolic milestone of 500 ppm CO2e.  

Observation by CO2.Earth:  No media releases or coverage of the 500 ppm CO2e milestone announcement has been found on any website in the world, including the UNFCCC website which has an ultimate objective to stabilize the concentration of greenhouse gases in the atmosphere.  

2020 05 15 at 8.20.58 AM screenshot noaa 2019 co2e 500 ppm

The above graphics are a screenshot from the NOAA AGGI Intro webpage.



More information about the greenhouse gas index is posted on the NOAA AGGI Intro webpage.  Technical details, including a table with annual CO2-equivalents since 1979, are on the full NOAA AGGI page.   

The index quantifies the global climate forcings of CO2, CH4 (methane), N2O (nitrous oxide), CFC12, CFC11 and 15 minor GHGs. 

Changes in the AGGI are reported from 1979 (AGGI = 0.785) until present (2019: AGGI = 1.45).   The index uses 1990 as a baseline year with a value of 1.  The index increased every year since 1979.  The chart below shows the similar trajectory of CO2 and the AGGI.

NOAA Annual GHG Index

Source Graphic  NOAA Annual Greenhouse Gas Index (AGGI)



Global Average Abundances of Major, Long-Lived Greenhouse Gases

Global Average Concentrations for Major GHGs

Source Graphic  NOAA Annual Greenhouse Gas Index (AGGI) 





Butler, J.H. & Montzka, S.A. (2015) The NOAA Annual Greenhouse Gas Index (AGGI). Published online Spring 2015, retrieved October 5, 2015, from