Earth's CO2 Home Page

Atmospheric CO2

October 2021

parts per million (ppm)

Mauna Loa Observatory, Hawaii (NOAA GML)

Preliminary data released November 5, 2021


Keeling Curve Monthly

Latest monthly CO2 level in the Earth's atmosphere


    CO2 Data


    NOAA-ESRL  Trends in atmospheric CO2

    Scripps UCSD  Keeling Curve +  Scripps CO2 Program (reposted data)  Daily CO2  |  Weekly CO2  |  Monthly CO2  |  Annual CO2  Track The Trend


    Show the Trend  Add a 'KC Monthly' CO2 widget to your site or blog



CO2 Updates for Canadian Weekly Newspapers

Dear newspaper publishers and managers,

We are a small team of volunteer, climate-concerned Canadians affiliated with the website.  And we have an offer and a request for you to consider. 

First, here's the offer.

For free, we want to give you the best graphics, information and assistance available for printing CO2 updates.  Why?  We want to make it easy for you to keep your subscribers and other readers up to date on the world’s leading indicator of local and global environmental health.  

Every Sunday or Monday, we publish a visual graphic with the latest CO2 levels, a graphic like this:

Atmospheric CO2 (weekly)

This graphic is an auto-updated web widget you can add to your website.
Click here for code and simple instructions to add it.

This graphic is an RGB thumbnail which we update every week.  Also, we have a larger, CMYK file linked at the bottom of this page which is now ready and continually updated for weekly publication in newspapers and other print media. Plus, we have larger RGB version available for digital publication online.  The CO2 graphic files linked below are large so they can be scaled down to the size and quality which works for your publication. 

We are sharing the modest selection of resources we have produced so far with English-speaking papers in Canada before we actively reach out to papers in other languages and countries. In the background, we are working to add more CO2 size and design options, resources and supports that are of actual use to newspapers, firstly here in Canada

Second: Our request.

We want to learn what kinds of content, information and support would make it easy for your paper to publish CO2 updates that existing and new readers will come to expect.  To find out, we created this 5 minute survey which we hope you and other weekly paper publishers will fill out.  

[insert survey link]

Alternatively, bypass the survey and email your thoughts to Guy Hanchet at This email address is being protected from spambots. You need JavaScript enabled to view it. (or request a 10-minute phone interview). 

We are.... 


Guy Hanchet, (Ontario)

Professor Rick Kool, Royal Roads University (BC)

Michael McGee, M.A., CO2.Earth & Show.Earth (BC)



PS: You may be interested in these resources:

Show.Earth | Install a Weekly CO2 Website Widget

CO2.Earth | CO2 for Print

CO2.Earth | media..


Examples of CO2 Media Broadcasts

co2earth exampels of co2 broadcasts bnnr mohnish landge 7Ee5tUGlGZM unsplash adapted 1200w

OK. What do the following cities and communities have in common?

  • Dove Creek, Colorado
  • London, England
  • Nelson, British Columbia
  • Peterborough, Ontario
  • Vancouver, British Columbia
  • Victoria, British Columbia

The name of this webpage is a clue.  The page spotlights the examples of different types of media organizations and how they broadcast and publish global CO2 levels for their audiences and readers. 

And so, each city and town in the list is the home of a media station or outlet that has taken the small but important step of adding atmospheric CO2 to the content they broadcast, print and share.  Each place is the home of a media-broadcast innovator which does something that is simple but imporant, and which, so far, very few media outlets have started. 

This page is for media producers, users and advertisers who may be thinking of whether or how to make global CO2 updates a regular part of the media content they generate or consume.  The examples are provided to help you and others visualize what some new and different CO2 media products could look like.  The examples are presented with links to reasons that media outlets have given for putting global CO2 levels on display.  Plus, this page assembles a variety of sources and resources that can be useful for starting and maintaining a new CO2 broadcast.

The CO2 media examples are organized into tabs.  Other CO2.Earth pages of potential interest are listed below. 

  • Daily CO2  A leading source of CO2 data for media broadcasters  
  • CO2 Records   A list of all-time high-levels of CO2 in the atmosphere
  • CO2 for Print   Graphics available for use by newspapers and print media
  • CO2 Q&As   In Progress: A future learning hub for finding info about CO2 levels


CO2 Broadcasts on the Radio


CO2 is in the air and on air when you're tuned into Canada's CBC Radio One on Vancouver Island.   We are pleased to spotlight Gregor Craigie and the Canadian Broadcasting Corporation as pioneers in CO2 broadcasting.  It's the first radio station we know of to broadcast global CO2 levels on a daily basis. 


CBC Radio One (Canada)

Since September 2019, the morning business segment of CBC Radio's On The Island now includes the latest daily CO2 reading as part of its stock market update.  The CO2 readings were added by Gregor Craigie, the host of On The Island which broadcasts to Greater Victoria and the whole of Vancouver Island, and to anyone who tunes in with the CBC Listen app for web or mobile.  

The show illustrates how simple it is to make CO2 a part of a radio show that serves as a local journal of record.  It's "must listen" example for hosts of radio shows, station managers and network executives.   And it's an example that listeners can share with the people who program and present information on the station and shows they listen to. 



Oct 15 2019: CBC - On the Island (recording via SoundCloud) | Daily Market CO2 Stock Report - Gregor Craigie

Dec 18 2020: CBC - On the Island | If pollution is dropping during the pandemic, why is CO2 rising?  (Interview with Dr. Zwiers)

Recent MLO data for broadcasts: CO2.Earth  | Daily CO2




Sep 24 2019: CBC Radio One (8 minutes) |  The relationship between the stock market and CO2 emission levels On the Island with Gregor Craigie
Host Gregor Craigie spoke with Rick Kool, a professor in the School of Environment and Sustainability at Royal Roads University. Professor Kool argues that media outlets should give a daily report on the amount of CO2 in the atmosphere, alongside market numbers, to highlight the connections between industrial society and the atmosphere. (Unfortunately, access to the CBC recording expired after 2 years.)

Sep 24 2019: CBC News Include CO2 emission levels in stock market reports, says B.C. professor
When the market goes up, so do CO2 emissions, says Rick Kool. 

Oct 16 2019: Twitter @billmckibben  | Tweet by Bill McKibben 



CBC Listen | On The Island with Gregor Craigie

CBC Listen | What on Earth with Laura Lynch (another CBC radio show to check out)

CBC Listen | Live Radio and On Demand

CBC Media Centre | About Gregor Craigie

Twitter | @gregorcraigie and @CBContheisland

CBC Listen Mobile Apps | Google Play + Apple App Store

CBC Programs | On the Island



CO2 Broadcasts on Television

To our knowledge, the first regular TV broadcast of atmospheric CO2 readings was started by DCTV in January 2011 in Colorado, and the second by Global News Peterborough in May 2021 in Ontario.   We are sharing these pioneering examples for television professionals, advertisers and audiences for considering the start of CO2 readings to serve their station, network, community or market.   


Global News - Peterborough (Canada) 

On May 10, 2021, Global News on CHEX in Peterborough Ontario made daily CO2 levels a regular part of the weather almanac it presents weekdays at 6 p.m.  CO2 reporting was initiated by Peterborough's trusted weather specialist Caley Bedore.  Peterborough is east of Toronto.



May 10 2021: Twitter via @CaleyBedore CHEX Global | TV Clip (38 sec): First daily CO2 report (417.79 ppm on May 9) on the station and network

Recent MLO data for broadcasts: CO2.Earth  | Daily CO2



May 11 2021: Global News  |  TV Clip (2 min 41 sec): CO2 levels in atmosphere rise dispite emissions drop during pandemic

May 11 2021: Global News  |  Article: CO2 levels in atmosphere rise dispite emissions drop during pandemic



Global News | Peterborough

Twitter | @caleybedore and @CHEXNewswatch



Delores County TV (DCTV) in Dove Creek, Colorodo is the first television station on the planet to begin regular broadcasting of CO2 levels in the Earth's atmosphere.  This small, community-funded television station serves communities in the Four Corners area where four Amercan states converge: Colorado, Utah, Nevada and New Mexico.  

Broadcasting of weekly CO2 averages were initiated in January 2011 by Dan Fernandez, Director of DCTV and Manager of the Delores County Broadcast Network (DCBN).   Soon after broadcasting began, Fernandez started a long collaboration with Mike McGee, creator of CO2.Earth ( at the time), to produce graphic the station uses to show weekly CO2 levels in its newscasts.  The graphic uses weekly average CO2 levels which is measured at the Mauna Loa Observatory and made public by scientists at NOAA headquarters in Boulder, Colorado.  Since 2012, young student newscasters with the 4-H club have been using the CO2 graphics in the local DCTV news programs they deliver to viewers in their Delores County community.  

Many recordings of the newscasts have been uploaded to the DCTV YouTube Channel.  Video samples from the DCTV YouTube channel can be accessed with the links below. 


A Decade of CO2 TV Broadcasts (sample newscasts)

Tues. May 4, 2021: DCTV YouTube | DCTV News Program for March 4 2021 (start at 23:20)

Mon. Mar 1 2021: DCTV YouTube | 4H Kids News Program for March 1 2021 (start at 19:30) 

Mon. Sep 4 2017: DCTV YouTubeNews at Noon September 4, 2017 (start at 15:27)

Mon. May 29 2017: DCTV YouTube | News at Noon May 29, 2017 (start at 19:53)

Mon. Dec 14 2015: DCTV YouTubeNews at Noon December 14, 2015 (start at 15:47) 

Mon. Dec 7 2015: DCTV YouTubeNews at Noon December 7, 2015 (start at 11:53)

Wed. Oct 4 2012: DCTV YouTube | DCTV 4H Kids News for Oct 4 2012 (start of 9:43)

Tues. Sep 27 2011: DCTV YouTube | DCTV 4H Kids News for Sep 27 2011

Thur. Sep 8 2011: DCTV YouTube | DCTV 4H Kids News for Sep 8 2011 (start at 9:04)


RESOURCES FOR TV Broadcasting of Weekly CO2 Levels

Recent MLO data for broadcasts: CO2.Earth  | Weekly CO2

Download recent weekly graphics for TV broadcasts and print media: CO2.Earth  | CO2 for Print



Wayback Machine (2012): (predecessor of CO2.Earth) | DCTV: The first TV CO2 broadcast on Earth  



Delores County | Broadcasting Network (DCBN) and DCTV

DCTV Daily News - Facebook | @DCTVDailyNews

DCTV Daily News - YouTube Channel Videos | DCTV Daily News



CO2 in Print & Digital Media


The Guardian (UK)

Citing its pledge to give the climate crisis even greater priority, plus the 3,000 articles it wrote for its 100 million readers, the Guardian claimed on October 5, 2020, that it is "a leading voice in the fight to save the planet."  The links on this page back to the Guardian--the key articles, its pledge on environmental matters, it's team of dedicated environmental writers, its open sharing of reporting methods and its CO2 updates--present a considerable package of evidence that it is doing what it said.  

Here's a question to consider. If there is another newspaper or media company that is doing more on climate matters than the Guardian, then what company is it?  What media organization is approaching or surpassing the Guardian with respect to some aspect of climate or environmental writing?  We assume there are others.   If you know of another media company that is an examplar in an area that deserves to be mentioned on this page, please name the company and point to reasons why you consider it an examplar. 

Whether the Guardian is the leader in climate and environmental writing, or more simply a leader as it says, the organization is modelling a whole package that stands out here at CO2.Earth.   Actions taken by the Guardian suggest that leadership in responsible environmental reporting means that CO2 levels get included on its pages each day it puts out a new edition.  It shows that broadcasting CO2 levels is important and simple to do.  

If you are questionning the need or utility of CO2 broadcasting because a majority of media companies stick to data on sports, weather and markets, notice that this leader in responsible enviornmental reporting has been reporting CO2 levels since April 2019.  And ask how could it achieve that leadership without CO2 on its pages and close to its readers as they read about climate, weather, business, sports, travel, entertainment, fashion, politics and health.  Could it suggest that it is a leader in climate and enviromental writing with no ink for the CO2 levels each day those levels change?  The example of the Guardian makes it harder for other media companies to claim that they are at the head of the pack on sustainability or responsible communications while leaving their readers or audiences to look elsewhere for CO2 updates.  

CO2 publication looks like an integral part of the multiple ways that the Guardian is writing on climate and environmental matters.  It is an approach to consider following in some way.  The links below show what the Guardian is doing, and other examples on this page show there is a variety of ways to broadcast CO2 levels.  For the more challenging task of writing about climate and environmental issues, consider coming back to the Guardian from time to time as a useful resource.



May 2021: Weather page | MLO CO2 for May 18 2019 plus 3 annual comparisons for week of May 9-15, 2021

Nov 2019: Excerpt of email to digital subscribers | MLO CO2 levels for week of Oct 27-Nov 2, 2019

May 2019: Weather page | MLO CO2 for May 20 2019 plus 3 annual comparisons for week of May 12-18, 2019



Recent MLO data for publication: CO2.Earth Weekly CO2 + NOAA GML | Weekly CO2

Download recent weekly RBG graphics: CO2.Earth  | CO2 Earth via



Dec 14 2018: The Guardian | The letter to the Guardian that sparked its CO2 reports (see comment by Daniel Scharf) 

Apr 5 2019: The Guardian | Why the Guardian is putting global CO2 levels in the paper every day

Apr 5 2019: Twitter | @gretathunberg on Guardian decison to publish CO2 levels with weather reports

May 17 2019: The Guardian | Why the Guardian is changing the language it uses about the environment

Oct 15 2019: The Guardian | Environmental pledge 2019

Oct 16 2019: The Guardian | It's a crisis not a change: 6 Guaridan language changes on climate matters

Oct 31 2019: The Guardian | Guradian environment writers



The Guardian | International edition online

The Guardian | Environment section

The Guardian | Climate change section

The Guardian - Facebook | @theguardian

The Guardian - Twitter | @guardian


Nelson Daily News (Canada)

Each week from late 2009 until July 2010, the Nelson Daily News published a CO2 bulletin which was designed by Mike McGee, creator of, and Michael Jessen, climate change columnist at the paper.  Most bulletins featured current CO2 readings for weekly or monthly periods with multi-year comparisons.  Some bulletins put a spotlight on emissions and increases in global average temperature.  

The CO2 bulletins were sponsored by a real estate agent in the Kootenay region of British Columbia (Nelson and surrounding communities).  They stopped when the newspaper century-old newspaper was sold and closed by the new owners.  However, the publication of CO2 bulletins as paid advertising space is a model that a paper's sales staff or an advertiser could make happen, and which CO2.Earth can assist through production or guidance.  



Jan 11 2010: NDN | CO2 Bulletin tear sheet (pdf)



Jan 11 2010: NDNCarbon counter keeps eye on environment: Part 1 (page 1) 

Jan 11 2010: NDNCarbon counter keeps eye on environment: Part 2 (page 4)



Wikipedia | Nelson Daily News (1902 - 2010)

Original Owner | Glacier Media Group

Jul 31 2020: Greg Nesteroff ( | Former home of the Nelson Daily News



Georgia Strait / Tim Louis Column (Canada)

Tim Louis is a lawyer in Vancouver, and former city councillor and park commissioners in that city.  He is also a long-time blogger whose articles on a range of social issues are regularly re-printed in Vancouver's Georgia Straight, the largest urban weekly newspaper in Canada.  

Starting with his blog post of September, 2019, Tim Louis adds the latest daily CO2 level at the bottom of each post.  He also includes a comparison for the same day one year ago.  Since April 23, 2020, the Georgia Straight has kept the plain-text CO2 updates when publishing his blog posts.



Apr 3 2021: The Georgia Straight | Tim Louis: David Eby--a big heart and no fear when it comes to housing

Apr 23 2020: The Georgia Straight | Tim Louis: Tighter gun controls are the best tribute to Nova Scotia's victims



Sep 24 2019: | Human change NOT climate change! (CO2 snippet: 408.85 ppm)



The Georgia Straight | Online edition

The Georgia Straight | Recent stories by Tim Louis

Publisher  | Vancouver Free Press Publishing Corp (acquired Mar 2020 by Media Central Corp)

The Georgia Straight - Twitter | @georgiastraight

The Georgia Straight - Facebook | @georgiastraight

Tim Louis - Twitter | @tim_louis


Globe & Mail (Canada)

The Globe & Mail does not yet publish CO2 updates.   But like many national newspapers, the 'Globe' publishes the latest market numbers, weather forecasts, baseball box scores, horoscopes, crosswords and sudoku.  For now, we are simply spotlighting the front page of the July 29, 2010 edition of the Globe & Mail.  This is a front page with 10 graphs of observed changes to the earth which are all consistent with global warming.   

Jul 29 2010:  Globe & Mail | Signs of warming Earth 'unmistakable' Page 1  + Page 2

The article presents no chart for carbon dioxide or the level of any other greenhouse gas.   We think that international, national, regional and community newspapers can and should consider the addition of regular CO2 updates right away.  In a way, it is more important than the graphs on the cover of the July 29, 2010 edition of the Globe & Mail.   CO2 is humanity's chief greenhouse gas.  It's the main byproduct of the activities of Civilization that are driving a cascade of consequential changes to the life-supporting biosphere.  It's the main thing before the 10 charts the Globe & Mail hoisted onto page 1.  

Just as important, if not more, CO2 is the chief trend to flatten and turn down if national, regional and community newspaper markets of the world are going to have a chance of flourishing in the years, decades and centuries ahead.  Hoist CO2 levels onto the front page.  Or on the first page of the business section.  Or with the weather report.  Or in more than one place.  Is there any excuse for blocking CO2 from view?  Whatever your opinion on the matter, thanks for taking a moment to consider ours.


Related Print Media Articles

May 10 2019: National Post | Kool: It's worth a daily reminder: When markets are up, environment is down

Sep 25, 2019: Crossroads (Royal Roads University) | Kool: If markets are up, environment is down


Print Media Resources

Download recent weekly graphics for print media: CO2.Earth  | CO2 for Print


In Development

A few projects and initiatives are in the pipeline.   The information below provides a snapshot of current activities and upcoming products to advance the regular display and broadcasting of CO2 updates for the general public.  


Prototype: 'Aloha Daily' Email Service

Created by A. Davey (UK) and M. McGee (Canada), a working prototype automatically sends daily CO2 updates almost the moment that NOAA scientists release a new day's average of measurements made at the Mauna Loa Observatory on Hawaii's Big Island.  It's a simple, auto-generated email that we cally Aloha Daily.  

The next step is the addition of a module that allows people to subscribe and unsubscribe.  To get added to the subscriber's list now, to start the emails when Aloha Daily goes public, send a short request to This email address is being protected from spambots. You need JavaScript enabled to view it..  


Prototype: Daily CO2 Website Widget

Created by A. Carpentieri (USA), M. McGee (Canada) and A. Davey (UK) in 2021, a simple, new website widget is putting CO2 on display with updates each day when NOAA scientists release a new day's average for CO2 measurements.  

The widget is presently in the testing phase.  To see the. test version of the widget in action, go to the University of Cambridge's Climate Lecture Series homepage and look for a grey box that displays the daily CO2 level.

With the testing so far, we know our basic prototype works well on secure (https://) and traditional (http://) websites built on a WordPress or Joomla CMS.  We're keen to confirm that it works well on sites with other CMS types of regular html.  




Mike McGee (Canada)

Suppliers of Graphics:

Mike McGee (Canada)

Glenda Barstow (Canada)

John Harnett (Canada)

Guy Hanchet (Canada)

CO2 Data Sources:

Dr. Pieter Tans et al / NOAA GML (USA)

Daily CO2 API:

Adam Davey (UK)

Mike McGee (Canada)

Daily CO2 Widget:

Adam Carpentieri (USA)

Mike McGee (Canada)

Adam Davey (UK)

CO2 Display Advocates:

Dr. Rick Kool (Canada)

Guy Hanchet (Canada)

Malaika Collette (Canada)




















Say 'Aloha'

Want to connect?   Interested in our mission to make CO2 visible for all?  We're reachable at This email address is being protected from spambots. You need JavaScript enabled to view it..



Q&A: Why doesn't CO2 Earth data match the Bloomberg Carbon Clock?


How is it so that the figure you publish is 412.44 and Bloomberg live data is 413.05??

Figure 1: Screenshot of Rob’s Facebook Question:

About the Question:
• Rob asked via Facebook Message to CO2.Earth Facebook
• Date of Question: Tuesday August 25, 2020
• Date of Response: Saturday August 29, 2020


On Monday August 24, 2020, CO2.Earth Facebook posted the following graphic with the weekly mean for CO2 readings at the Mauna Loa Observatory, that being 412.44 ppm:

Figure 2: CO2.Earth Graphic Showing MLO CO2 Readings from NOAA

Graphic: CO2.Earth Facebook post of August 24, 2020

August 29, 2020, after receiving the question, the Bloomberg Carbon Clock displayed atmospheric CO2 as 412.96 ppm (and falling) on the screen recorded in Figure 3:

Figure 3: Screen Shot A of Bloomberg Carbon Clock Home Page



Rob asks a good question: How is it so that the figure you publish is 412.44 and Bloomberg live data is 413.05?

Here is the difference.

CO2 Earth spotlights the latest atmospheric CO2 averages for CO2 levels that have been measured and reported as preliminary readings by NOAA and Scripps at the Mauna Loa Observatory. CO2 Earth posts CO2 averages on multiple timescales that include daily, weekly, monthly and yearly. Rob’s question refers to the weekly MLO CO2 average from August 16 to 22, 2020, which NOAA measured and reported, and CO2 Earth posted, all in near-real time.

The Bloomberg Carbon Clock is a machine-generated estimate of current levels second-by-second. But the Bloomberg Carbon Clock is not a live data feed of the CO2 level at this moment. It does not show the latest observed level of CO2. It is an algorithm with a methodology that is detailed in a Bloomberg paper that states:
The Bloomberg Carbon Clock is projected from the average of the four most recent NOAA weekly estimates, and therefore may be slightly lower or higher than other measures at any given moment. (Dash et al., 2016, p. 6)
The Bloomberg estimates are continually updated on a rolling basis using the latest 4 weeks of NOAA CO2 measurements.

Although the Bloomberg estimates do not match the CO2 measurements at MLO, estimates reflect the seasonal fluctuation in CO2 levels driven by vegetation cycles in the Northern Hemisphere. For this reason, the second-by-second Bloomberg estimate is falling as generally expected for August 29 this year, or any year. To illustrate, the screen shot below shows the Bloomberg CO2 value just more than 5 minutes after Figure 1.

Figure 4: Screen Shot B of Bloomberg Carbon Clock Home Page

Compare Figures 5 and 4 to see that the CO2 estimate on August 29, 2020, is falling, not rising. This general trend is expected and consistent with the MLO CO2 record. As acknowledged in the Bloomberg paper, the Bloomberg Carbon Clock does not show the ongoing up-and-down variability or noise on timescales of a week, day, minute or second.

Links & References (as of August 29 2020):

Bloomberg Carbon Clock

CO2.Earth Facebook page

CO2.Earth Facebook post of August 24, 2020

Dash, J.W., Zhang, Y., Migliozzi, B. and Roston, E. (2016). A forecast for global CO2 levels: Working Paper. Retrieved August 29, 2020 from Bloomberg LP

Appendix A: Bloomberg Carbon Clock Methodology

The material below is copied from the bottom of the Bloomberg Carbon Clock landing page.

What the Clock Shows
Fossil-fuel burning and deforestation are the main drivers of global warming. The CO2 they give off makes up more than 75 percent of annual climate pollution. The Bloomberg Carbon Clock is a real-time estimate of the global monthly atmospheric CO2 level.
The following methodology is a nontechnical explanation of how the carbon clock works. The full version, which includes all the math and science underpinning the project, can be found HERE.
The graphic draws on CO2 data released from the NOAA Mauna Loa Observatory. The Scripps Institution of Oceanography pioneered CO2 monitoring in March 1958 at the observatory in Hawaii. The National Oceanic and Atmospheric Administration started a parallel effort there in May 1974. Today, NOAA maintains a global network of observatories, sampling towers, flights, and flasks to measure the composition of the atmosphere.
To estimate real-time atmospheric CO2 levels between data releases, and forecast them, we analyze the three most recent years of data and use an average of the most recent four weekly data releases. That analysis is then fed into an algorithm. Each new weekly data point starts a new analysis that yields updated daily clock values and a trend line (shown in yellow on the graphic).
Two projections are made each week, a four-week daily forecast that runs the clock, and an annual forecast that projects the current trend one year into the future. The latter is appended to the graphic where the data end.
The Forecast
The carbon clock projections are the result of two mathematical procedures:
1. The "wavelet”: This is an equation that "learns" the long-term trend line of CO2 and adds on the seasonal peaks and troughs—the squiggles that pass above or below the trend line every half-year or so. It calculates the long-term trend from monthly data over the previous three years, which it uses to derive an initial rough daily forecast for one month into the future.
2. The Singular Spectrum Analysis (SSA) algorithm: This is a statistical tool that improves on the wavelet. It calculates the probable future trend of the data by running possible forecasts over and over until they start to converge. When they do, it quits, and outputs its best estimate for every day of the month. The final step is to use linear interpolation–basically an advanced mathematical method for connecting the dots—to turn the daily values into the second-by-second readings seen on the Clock. The clock displays eight decimal digits, determined by the model.
The shaded areas adjacent to the yellow trend line are “uncertainty bars,” which represent an average of the difference between the wavelet- and the SSA-determined trends. The year-ahead forecast on the graphic has shade bars that show where the projected path of CO2 is likely to fall with 95 percent confidence.
About CO2
The background atmospheric CO2 concentration is uniform around the world. Daily, weekly, monthly, and annual averages all differ superficially because of short-term variation—basically, weather—that can mask the long-term upward trend. Because the Bloomberg Carbon Clock is projected from the average of the four most recent NOAA weekly estimates, it may be slightly lower or higher than shorter-term measures at any given moment.
The Scripps CO2 program maintains a helpful graphic on its website that displays CO2 data averaged over several time periods. The hourly, daily, and weekly averages each show decreasing levels of variability. The long-term trend becomes more focused monthly and annually.
CO2 Data:
The Scripps CO2 time-series is known as the Keeling Curve, after the scientist who initiated and maintained it for almost a half-century, Charles David Keeling.
The animated graphic below the Clock is a combination of several CO2 time series. Moving from the top right, to the bottom left, the Curve is assembled from these sources:
The Year Ahead: The model projects forward one year, to give a visual estimate of the trajectory of CO2. The annual forecast carries a 95% confidence band. The forecast trend is shown as an extension of the yellow historic trend; they are determined the same way, by the average of the difference between the wavelet and the SSA algorithm results.
May 1974 to the Present: Mauna Loa Observatory average CO2 record, maintained by NOAA.
March 1958 to April 1974: Scripps Institution of Oceanography Mauna Loa averages.
Ice Core Record: Fossilized air trapped in Antarctic and Greenland ice has allowed scientists to estimate atmospheric CO2 content going back 800,000 years. The highest value in this record is 298.6 ppm, seen about 330,000 years ago. These records are available online as the Antarctic Ice Core Revised Composite CO2 Data.
Earth Images:
Satellite images of the Earth were made by the Japan Meteorological Agency weather satellite, Himawari-8. The imagery is processed at Colorado State University in cooperation with the National Oceanic and Atmospheric Administration and the Japan Meteorological Agency. The images were assembled into video by Blacki Migliozzi, with advice from Dan Delany. The image archive can be found here.
Several scientists either read the technical working paper in draft or provided helpful conversations about the methods described here. They include:
* Michael Ghil, Department of Atmospheric and Oceanic Sciences, UCLA
* Dmitri Kondrashov, Department of Atmospheric and Oceanic Sciences, UCLA
* Mahé Perrette, Potsdam Institute for Climate Impact Studies
* Michael Mann, Earth System Science Center, Penn State University
* Andrew Robertson, International Research Institute for Climate and Society, Earth Institute, Columbia University
* Gavin Schmidt, NASA Goddard Institute for Space Studies
* Pieter Tans, Earth System Research Laboratory, NOAA
Graphic by: Eric Roston & Blacki Migliozzi
Data modelling by: Jan Dash & Yan Zhang
Design & Development by: Blacki Migliozzi, Adam Pearce & Mira Rojanasakul
Published: December 1, 2015
Data updated: May 22, 2020

CO2 Past.  CO2 Present.  CO2 Future.