Global Carbon Emissions

Global carbon (C) emissions from fossil fuel use were 9.795 gigatonnes (Gt) in 2014 (or 35.9 GtCO2 of carbon dioxide).  Fossil fuel emissions were 0.6% above emissions in 2013 and 60% above emissions in 1990 (the reference year in the Kyoto Protocol).

Based on a 2015 GDP forecast of 3.1% by the International Monetary Fund, the Global Carbon Project projects a 2015 decline of 0.6% in global emissions.


Mauna Loa CO2 Board


The Most Current CO2 Data on Earth | August 2015

Atmospheric CO2  |  Mauna Loa Observatory

NOAA-ESRL  |  Data available since 1974

Scripps CO2 Program  |  Data available since 1958


Latest Data



Last Update 


click here or here 

398.67 ppm

Aug 21 2015**


Aug 21 2014

Scripps CO2

August 23 2015


click here

398.24 ppm

August 27 2015**

no comparison

is available

for 2014



August 28, 2015


399.13 ppm

August 16 - 22 2015


August 16 - 22 2014



August 28 2015

also see historical Scripps weekly CO2 data here


403.70 ppm

May 2015


May 2014

Scripps CO2

June 4 2015


401.30 ppm

July 2015


July 2014



August 5, 2015 


398.60 ppm*




Scripps CO2

June 4, 2015


398.55 ppm


396.48 ppm




August 5, 2015

* 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. 

Atmospheric CO2     |  Global Data

NOAA-ESRL Cooperative Air Sampling Network 

Global Data Available Since 1980


Latest Data 


Last Update 


400.11 ppm

June 2015 

397.52 ppm 

June 2014

August 5, 2015 


397.16 ppm 


395.22 ppm 


August 5, 2015


The Global Monitoring Division of NOAA-ESRL operates staffed atmospheric baseline observatories at the following locations:


The NOAA-ESRL-GMD CCGG (carbon cycle greenhouse gas group) cooperative air sampling network effort began in 1967 at Niwot Ridge, Colorado (USA). Today, the network is an international effort which includes regular discrete samples from NOAA-ESRL baseline observatories, cooperative fixed sites, and commercial ships.

Air samples are collected through the NOAA-ESRL global air sampling network, including a cooperative program for the carbon gases which provides samples from about 100 global clean air sites, including measurements from ship routes at 5 degree latitude intervals.  

Air samples are collected approximately weekly and analyzed in Boulder, Colorado (USA). 

Sources:  NOAA-ESRL CCGG  |  High-Resolution PDF


Mauna Loa | Atmospheric Science and Wonder


Mauna Loa Science & Wonder

At the end of March 2011, globe-trotting climate photographer Gary Braasch paid a visit to the Mauna Loa Observatory in Hawaii. It didn’t take long for Braasch to come away with a stunning set of images and informative commentary.  Check out his photolog, reposted below with permission.  (Or, skip over to Gary Braasch's to see his Mauna Loa science photographs and other climate change photos from around the world.)   It's like getting a personal tour of the world famous observatory and the atmospheric science that happens 24-7 near the top of the mountain, 3.4 kilometres above sea level.

mauna loa noaa co2 vial aerosol laser co2 tower copyright 2011 braasch 650w 100k (1)

The following is reposted from with permission.

April 2011

Greenhouse gases increase at record rate in 2010 to highest ever recorded.

Report from Mauna Loa Observatory, Hawaii

mauna loa noaa co2 vial aerosol laser co2 tower copyright 2011 braasch 650w 100k (1)

At night at the NOAA atmospheric and space observatory on the upper flanks of Mauna Loa, Hawaii, a visitor walks along walkways between installations. This is NOAA's main location for direct measurements of many components of the air, the sun and the universe, including the amount of carbon dioxide in the atmosphere. Air is collected on a 27 meter tower (left) and analyzed for CO2 content. CO2 alone is responsible for 63 percent of the warming attributable to all greenhouse gases. At right, a powerful laser beam is used to measure aerosols in the air up to 45 km into the stratosphere.

mauna loa co2 laser dust noaa night march 2011 copyright braasch 648w

Overview of NOAA's atmospheric and space observatory, at 3400 meters on the northeast flank of Mauna Loa volcano in Hawaii. The observatory consists of 10 buildings from which up to 250 different atmospheric parameters are measured. Measuring carbon dioxide at this location, begun in 1958 at the request of Charles David Keeling of Scripps Oceanographic Institution, has created the longest continuous record of atmospheric CO2 concentrations available in the world. The resulting "Keeling Curve" showing the yearly seasonal fluctuation in CO2 and the rising rate of increase year to year has become central to the understanding of global warming. Average yearly CO2 concentrations here have risen from 315.98 parts per million (ppm) in 1959 to 389.8 ppm in 2010 -- an average growth rate of 1.4 ppm per year. However NOAA's Carbon Dioxide Information Analysis Center (CDIAC) reported that the average CO2 concentration at Mauna Loa in 2010 increased 2.39 ppm over the previous year. Mauna Loa is just one of the sites at which carbon dioxide is measured, and CDIAC calculated that the globally averaged increase from 2009 to 2010 was even more -- 2.76 ppm -- the greatest since 1998 and the second greatest increase since records began. At this rate the 400 ppm level will be reached in less than four years.

We are already on a continuum of climate change effects: glaciers are melting, sea level is rising, habitats are moving, species are being pushed toward extinction and millions of people are caught in severe weather events. Scientists advising the United Nations recommend the world should act to keep the CO2 levels below 400-450 ppm in order to prevent even more irreversible and disastrous climate change effects.

mauna loa noaa high co2 tower march 2011 copyright braasch 648w

Air is collected continuously near the top of a 40 m tower (and several shorter towers), and analyzed for CO2 content every minute by both Scripps Oceanographic Institute and NOAA. The accuracy of readings is tested by periodically measuring known quantities of CO2 kept in standard reference tanks in the lab. Results are computed hourly by NOAA. Worldwide coverage and comparison is insured by similar measurements at three other major observatories and hundreds of ground, airborne, balloon and tower CO2 measurements. Equipment in the nearby dome in this photo measures the thickness of the ozone layer -- a crucial protection from ultraviolet radiation and subject of a successful international agreement to limit chemicals which deplete the ozone. This agreement, the Montreal Protocol, is one model of international cooperation for the general good which influences the negotiations over the UN Framework Convention on Climate Change.

mauna loa noaa high co2 tower dobson ozone measurement dome march 2011 copyright braasch 648w

When Gary Braasch photographed the Mauna Loa NOAA observatory in late March 2011, the CO2 concentration was measured at more than 392 parts per million (ppm) -- nearly 3 ppm higher than in December 2010 and 112 ppm (40 percent) higher than the level that prevailed before the Industrial Revolution (approx 280 ppm). The burning of fossil fuels which began around 1750 and is considered the largest measured source of the added CO2, continues unabated worldwide. Scientists are very certain from thousands of studies and observations that this greenhouse gas, with contributions from methane and several other gases, warms the atmosphere increasingly as atmospheric concentrations go up ever higher. Analysis of our world's average surface temperatures by NASA and NOAA confirms that the Earth is warming: 2010 was the warmest year ever measured since the 1880s, slightly warmer than 2005, and 1.13°F warmer than the mid-20th century average. Given the huge volume of the Earth's atmosphere, the very slow pace of previous times of warming (like at the end of the last ice age) and the changes already seen due to warming over just the past several decades – scientists say the current temperature rise is unusual and very rapid. See Earth Under Fire: How Global Warming is Changing the World for details.

mauna loa co2 vial march 2011 copyright braasch 648w 4HICO2Vial392 65NOAA

A line-up of observatories above the clouds on Mauna Loa, Hawaii. From left to right: University of Hawaii VYSOS project aims at surveying all the major star forming regions for variable young stars; Solar Dome continues NOAA's measurement of the transmission of sunlight, the longest continuous record of this nature in existence; and the University of Hawaii GroundWinds instrument tests wind-measuring equipment that might later be deployed on a satellite.

mauna loa noaa observatories march 2011 copyright braasch 648w

Dr. John Barnes, NOAA's Mauna Loa Observatory Station Chief, in the laser radar room of the station. He is principal investigator for long term monitoring of stratospheric aerosols made up of sulfuric acid and water which cool the earth by reflecting the sun's light back into space, affecting solar radiation and ozone. Once each week Barnes aims a powerful pulsed laser into the stratosphere to light up tiny particles and create a high-resolution vertical profile of the optical scattering characteristics of aerosols, clouds, and the background molecular atmosphere. This technique is called LIDAR (Light Detection and Ranging) and measures back-scattered laser light from particles and molecules using four telescopes aimed at the laser beam at various heights above the station. These readings can be related to the total amount of stratospheric aerosols and the cooling they create. Dr. Barnes is holding a flash lamp used to pump the original Ruby laser which measured stratospheric aerosols from the early 1970's until 1998. The new, more powerful lidar started operation in 1994.

mauna loa noaa night laser measurements march 2011 copyright braasch 466wAs the laser shoots a green beam of light into the stratosphere from a hatch in the roof of the station, John Barnes settles into his office for several hours of monitoring the LIDAR equipment and the read-outs on his computer screen. Traces created from back-scattered laser light detected by the four telescopes show particulates and aerosols at miles above the station. In addition to the primary target of stratospheric aerosols, which are about 99 percent sulfuric acid/water droplets created by volcanos, the LIDAR can also detect tropospheric aerosols. Barnes said that during this time of the year there are often dust storms in China and the lofted dust and pollution can be carried out over the Pacific.  On the night these photos were made, March 31, 2011, one of these layers showed an elevated spike (red trace) at 5 km in the atmosphere above the observatory. 

One of the clearest skies on the planet gives Mauna Loa observatory, at 3400 meters (more than 11,000 feet), a spectacular backdrop of stars for its measurements. Here, Orion overlooks the neighboring CO2 tower on the right and the stratospheric aerosol-detecting LIDAR laser beam. These two measurements are both related to the temperature of the atmosphere: While CO2 molecules warm the atmosphere, the aerosols in the stratosphere reflect sunlight away from the Earth, and heavy concentrations, such as from explosive volcanic eruptions can cool the earth. Mauna Loa records clearly show the effect of increased aerosols from the large eruptions of El Chichon(1982) and Mt Pinatubo (1991) and resulting decreased solar radiation for a few years afterwards. The Pinatubo eruption cooled the Earth by about one degree F. for more than a year. Today's atmosphere is comparatively low in stratospheric aerosols, according to NOAA's John Barnes, so there is little contribution to reduction in the rising greenhouse warming.


More Gary Braasch photography:

Mauna Loa Photolog: April 2011 Newsletter  |

Climate Change Photographs  |

Gary Braasch Photography  |  Braasch Photography

Gary Braasch  Profile  |  GHG Photographers

Related Articles:

Mauna Loa CO2  |

Atmospheric CO2 Data  |


Photography and text Copyright © 2005 - 2011 (and before) Gary Braasch All rights reserved. Use of photographs in any manner without permission is prohibited by US copyright law. Photography is available for license to publications and other uses. Please contact This email address is being protected from spambots. You need JavaScript enabled to view it.. View more ofGary Braasch's photography here.

Gary Braasch, Photographer PO Box 1465 Portland, OR 97207 USA USA Cell: 503.860.1228


Scripps CO2 Data - Mauna Loa Observatory


scripps 189wThis page presents data for atmospheric CO2 measurements by the Scripps CO2 Program at the Mauna Loa Observatory in Hawaii.   Starting March 1958, the Scripps Mauna Loa data is the longest-runing, high-precision instrument record for atmospheric CO2. 

About the Scripps CO2 Program

The Scripps CO2 program was initiated in 1956 by Charles David Keeling who directed the program until he died in 2005.  The program is now operated by  Ralph F. Keeling who also runs the Scripps O2 Program that measures atmospheric oxygen and argon.   Both programs are based at the Scripps Institution of Oceanography in San Diego (La Jolla) California.

Scripps Data

Source Update:  June 4, 2015:

CO2Now Documents:       xl Scripps CO2 Data2 Data       pdf Scripps CO2 Data2 Data    

Scripps CO2 Program:      Scripps Source CO2 Data (CSV) 

Scripps Program

Scripps CO2 Program Home Page | Scripps CO2 Program


More from the Scripps CO2 Program

Keeling Curve Website  |  See the most recent daily average for atmospheric CO2

Keeling Curve Twitter  |  Daily averages for atmospheric CO2 (recent and historical)


NOAA CO2 Data |


NOAA Mauna Loa CO2 Data


NOAA release date for monthly CO2 data:

August 5, 2015  

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

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

xl NOAA CO2 Data for the Mauna Loa Observatory    pdf 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, 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 CO2molecules in every one million molecules of dried air (water vapor removed).  Annual mean CO2concentrations are the arithmetic mean of the monthly averages for the year.  Atmospheric CO2concentrations 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 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   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 email address is being protected from spambots. You need JavaScript enabled to view it..   

More Data


CO2 Acceleration  |

Mauna Loa Science and Wonder  |

CO2 Seasonal Cycle

In the late 1950s, Charles David Keeling figured out how to make precise measurements of CO2 concentrations in the atmosphere.  Within two years of starting his measurements, he had discovered a clear seasonal pattern in the background CO2 level. Keeling reported his discovery in a journal article in 1960 (Keeling, 1960).  A plot from that article is shown in Figure I (p. 200).  

Keeling CO2 Plot (Tellus, 1960)

Source Graphic  Scripps CO2 UCSD


At the Mauan Loa Observatory, Keeling found that the CO2 level rose from about October to May, and it fell a little less about   every May to October. This same seasonal cycle can be seen in the most recent CO2 readings at Mauna Loa.  See the monthly averages that are plotted below in red:

Current Mauna Loa CO2Source Graphic  NOAA-ESRL + High Resolution PDF


For comparison, a global average of CO2 readings from monitoring stations in both hemispheres shows an amplitude in the seasonal changes that is smaller than the amplitude at Mauna Loa in the Northern Hemisphere.  See the latest global CO2 average from NOAA below.

Current Mauna Loa CO2

In 2013, NOAA produced its GlobalView-CO2 animation which is shown below.  The animation shows different amplitudes in seasonal changes at different latitudes from the South Pole to the North Pole.

Current Mauna Loa CO2Source Animation  NOAA GlobalView CO2



Notice where the seasonal changes are smallest and where they are largest.  Can you think of why the amplitude at the Northern Pole is about average?  To see the differences in source data, compare atmospheric readings in Barrow, Alaska and the South Pole

In 2014, NOAA produced a similar animation in an HD video.  As you watch, notice the clarity of the longer-term patterns and trends.

 Source Video   YouTube    Animation & Info  NOAA website / CO2 Movie


More Info


Keeling Curve UCSD  Why seasonal CO2 fluctuations are strongest in north

Scripps CO2 UCSD  Learning from long-term earth observations

Climate Central  Keeling Curve

Encyclopedia of Earth  Mauna Loa curve

Science Daily 2009  All earth's seasons now arrive 2 days earlier




Keeling, C. D. (1960). The concentration and isotopic abundances of carbon dioxide in the atmosphere. Tellus, 12(2), 200-203. doi:10.1111/j.2153-3490.1960.tb01300.x [abstract + pdf]



CO2 Past.  CO2 Present.  CO2 Future.