CO2 Now

The world's most current data for atmospheric CO2 is measured at the Mauna Loa Observatoy in Hawaii.  Measurements are made and reported independently by two scientific institutions:  Scripps Institution of Oceanography and the National Oceanic and Atmospheric Administration (NOAA).  Monthly data is posted below.   

Mauna Loa CO2 Data Sets:

    Monthly     NOAA CO2 Data
    Weekly        NOAA CO2 Data

    Monthly    Scripps CO2 Data
    Daily           Scripps CO2 Data

  |  Monthly  |

NOAA release date for monthly CO2 data:

May 17, 2013

Atmospheric CO2
Mauna Loa Observatory (Scripps / NOAA / ESRL)
Monthly Mean CO2 Concentrations (ppm)
Since March 1958

The monthly MLO data set is reposted by CO2Now.org in 2 formats:

 NOAA CO2 Data for the Mauna Loa Observatory     PDF Version 

Source Data

Mauna Loa Monthly Mean CO2

Source data published by the National Oceanic and Atmospheric Administration (NOAA)

Mauna Loa Annual Mean CO2

Source data published by the National Oceanic and Atmospheric Administration (NOAA)

Data Notes

• At CO2Now.org, data for March 1958 - April 1974 was obtained by Charles David Keeling of the Scripps Institution of Oceanography (Scripps).  Data for CO2 since May 1974 was obtained by the National Oceanic and Atmospheric Administration (NOAA).   The Scripps Institution of Oceanography also maintains a CO2 monitoring program at the Mauna Loa Observatory.  Click here to access the Scripps data for the Mauna Loa Observatory.   
 
• Monthly mean CO2 concentrations are determined from daily averages for the number of CO2 molecules in every one million molecules of dried air (water vapor removed).  Annual mean CO2 concentrations are the arithmetic mean of the monthly averages for the year.  Atmospheric CO2 concentrations are expressed as parts per million (ppm).

• NOAA data published within the past year is preliminary and subject to change by NOAA due to its recalibration of the reference gas mixture used or other quality control procedures.  In some cases, data from earlier years may be changed for the same reasons.  Usually, these changes are minor. See the NOAA change log and notes that was started in August 2008 to keep a public record of the adjustments and reasons for the adjustments.   

• All data in this table is republished from the most current data available from NOAA.  Data is republished independently by Pro Oxygen at CO2Now.org to make it easier for people to see the latest atmospheric CO2 data and trend information.  A delay of 4 to 24  hours typically occurs between the release of monthly data by NOAA and the publication of updates at CO2Now.org.   The accuracy of republished data can be checked by reviewing the source data.   In the event that a publication error is detected, please send details to This e-mail address is being protected from spam bots, you need JavaScript enabled to view it .   

More Data

• EarthPolicy.org  |  Annual atmospheric CO2 concentrations from 1,000 AD to 2007
• NCDC NOAA  |  Vostock Ice Core CO2 Data
• CO2Now  |  Climate science data sources

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Related

CO2 Acceleration  |  CO2Now.org

Mauna Loa Science and Wonder  |  CO2Now.org

Data current as of May 2, 2013

Climate Sheet posts the world’s most current and important planetary data and targets – together in one place from leading global sources.  The CO2Now Climate Sheet enumerates the chain of causes that are driving humanity’s largest environmental crises – global warming, climate change and ocean acidification.  It also sets out key scientific markers for a stable climate system.

The Most Current CO2 Data on Earth

* Scripps annual CO2 data is calcuated by CO2Now using Scripps monthly CO2 data.
** Averages determined by Scripps and NOAA cover a different 24-hour time period due to time zone differences. 

NOAA-ESRL updated weekly data on May 13, 2013.  ("ppm" means parts per million)

The 2012 average annual concentration of CO2 in the atmosphere (Mauna Loa Observatory) is 393.84 parts per million (ppm).   The 2011 average is 391.65 ppm.  

For the past decade (2003-2012) the average annual increase is 2.1 ppm per year.  The average for the prior decade (1993-2002) is 1.7 ppm per year.    Annual data for 2012 was first posted January 3, 2013, by the Scripps Institution of Oceanography in the United States. 

Since the 1958 start of precision CO2 measurements in the atmosphere, the annual mean concentration of CO2 has only increased from one year to the next.   The CO2 data below provide a simple view of the annual trend. 

NOAA  |  In situ CO2 monitoring program

NOAA  |  Mauna Loa FAQs

NOAA  |  Location of the Mauna Loa Observatory

When carbon fossil fuels are extracted from the Earth’s crust and burned for energy, the emitted carbon dioxide is not visible.  That makes it hard to see and know how the use of fossil fuel adds up to serious global impacts like sea level rise, increased famine and species extinction.  The Carbon Impact Map is a climate literacy tool from CO2Now.org that traces the progression of carbon from its extraction and use to impacts on the planet and civilization to planetary feedbacks.   It presents an overall picture insix major steps.  The Carbon Impact Map is not an exhaustive list of the factors. 

http://forio.com/simulation/climate-development/

Global CO2 Budget 2010

GlobalCarbonProject.org posted data for the 2010 Global Carbon Budget on December 5, 2011.  Key findings are listed here:

* CO2 emissions grew 5.9% in 2010 to reach 9.1 GtC (33.5Gt CO2), overcoming a 1.4% decrease in CO2 emissions in 2009 

* Including land-use change and deforestation, in 2010 emissions reached 10.0 GtC (36.8 Gt CO2)

* As of 2009 developing countries now emit more than developed countries in terms of consumption, and China now emits more than the US in terms of consumption

>>>>  Links to the source data, credits and high-resolution images are given below.