Weekly means for atmospheric CO2 originate from the NOAA Earth System Research Laboratory (ESRL) and its Mauna Loa Observatory in Hawaii.


Weekly CO2

Mauna Loa Observatory | NOAA-ESRL



Atmospheric CO2

Last Week

April 16 - 22, 2017

409.61 ppm

1 Year Ago

April 16 - 22, 2016

407.48 ppm

10 Years Ago

April 16 - 22, 2005

387.49 ppm

  Data Updated:  April 23, 2017
  NOAA dataset: Web + .txt

weekly mean concentrations  |  ppm = parts per million


NOAA-ESRL and Scripps CO2 provide continually-updated graphics with daily and weekly data points plotted over multiple time periods.  Use the tabs below to view these graphics as well as links to the NOAA and Scripps websites.

Recent data is preliminary.  NOAA-ESRL is the only weekly dataset with values updated in real time.  Scripps CO2 posts a weekly CO2 dataset that is updated less frequently.


CO2 Past.  CO2 Present.  CO2 Future.