2023 Mauna Loa CO2 levels

[Renerpho]

latest reading 421.88ppm

https://keelingcurve.ucsd.edu/

That's actually not a new data point, but the value for November 16, recalibrated from the 421.89 I have in my post. There is no data for November 17+18 (too variable). The latest value now is 420.72 ppm for November 19, which may indicate that we are almost back to normal after the spike.

The keelingcurve.ucsd.edu website doesn't say what date their "latest reading" refers to, which makes it almost useless as a source for raw data.

[Stephan]

Another weekly average is available from Mauna Loa Laboratory on CO₂.

Week beginning on November 19, 2023:     421.21 ppm
Weekly value from 1 year ago:                 418.38 ppm
Weekly value from 10 years ago:              395.26 ppm
Last updated: November 26, 2023

The annual increase is at 2.83 ppm, which is above the last ten year average of 2.60 ppm/a. The daily readings have somewhat stayed at the elevated level it switched to on Nov 13. Some of the days were "unavailable" due to high intra-day variations.
The values have risen now by 3 ppm (this was the seasonal minimum two months ago) and is now only 3 ppm below the last seasonal maximum in May 2023.

[Chris83]

  Worth mentioning IMO , a reading at 434 ppm , and another at 429

  434 is the highest I have ever seen

[Sublime_Rime]

Sorry Chris, but those are hourly averages...

[Stephan]

Another weekly Mauna Loa CO₂ average is available.

Week beginning on November 26, 2023:     420.59 ppm
Weekly value from 1 year ago:                   417.81 ppm
Weekly value from 10 years ago:                396.21 ppm
Last updated: December 03, 2023

Since Nov 25 only one day passed the quality criteria of NOAA. All other days were "unavailable". Therefore is no further evaluation possible.
At least, it seems that the values slowly return to the lower ("normal") level.

[bosbas]

Thanks for your analysis, Stephan. I am guessing the last daily value under 420 ever in our lifetime is in the rear mirror; sad.

[Stephan]

Thanks for your analysis, Stephan. I am guessing the last daily value under 420 ever in our lifetime is in the rear mirror; sad.

You're probably right. 420 ppm = 50% higher than pre-industrial has been quite a benchmark. Maybe next seasonal minimum will go below this threshold for a few hours or days...

[Stephan]

It is the fifth of a month. Therefore new monthly averages of Mauna Loa CO₂ have been published.

November 2023:       420.46 ppm
November 2022:       417.47 ppm
November 2013:       395.16 ppm
Last updated: Dec 05, 2023

The annual increase is at 2.99 ppm (or 2.95 if I use the reading from last November, the value had been corrected insignificantly). Thie is much higher than the 10y average of 2.53 ppm/a and mirrors the increased production of CO₂ by human activity; independent from the talks at COP 28. It is also higher than the expected rate which should be (linearly fitted 1958-2023) at 2.44 ppm/a.

I set an index of 100 [338.75 ppm] for 1980. November 2023 is at 124.1 compared to that index.

[gerontocrat]

& here is the graph + global CO2 ppm

[Renerpho]

Week beginning on November 26, 2023:     420.59 ppm
Weekly value from 1 year ago:                   417.81 ppm
Weekly value from 10 years ago:                396.21 ppm
Last updated: December 03, 2023

The value has been updated today, after a daily average (420.04 ppm) has been added for December 1st. The new weekly average for the week beginning November 26th is 420.31 ppm.

[Stephan]

At the end of each weekend I deliver the latest weekly average on Mauna Loa CO₂.

Week beginning on December 03, 2023:     421.02 ppm
Weekly value from 1 year ago:                  419.23 ppm
Weekly value from 10 years ago:               396.43 ppm
Last updated: December 10, 2023

Once again I will not evaluate the data. Only two days had acceptable averages; the measurements were completely shut down from Dec 2 to Dec 5. I wonder whether they will "repair" the gap within the next days...

[Csnavywx]

Should see a gap up here on the 14th as an upper low and vorticity maximum pass north of ML, switching the flow to northerly aloft and mixing in higher CO2 mid-lat air.

[Stephan]

After two weeks of "unavailable" or even non-existing data a weekly average that can be evaluated has been pulished by NOAA.

Week beginning on December 10, 2023:     422.20 ppm
Weekly value from 1 year ago:                   418.81 ppm
Weekly value from 10 years ago:               396.39 ppm
Last updated: December 17, 2023

The annual increase is at 3.39 ppm which is clearly above the 10 year avearage of 2.58 ppm/a. The last two days showed again a jump by 1.5 ppm on a higher level. This finally made it above the 3 ppm/a increase rate. Nevertheless, even if this had not happened, the annual increase would have been at 2.9 ppm/a.

The gap I wrote about last week has not been filled yet. Maybe these two days will be missing forever.

[Renerpho]

My last update for the year (I won't be home over the holiday season). Next time I post about this will probably be in the new "2024 Mauna Loa CO2 levels" thread.

2023 is on track for an annual increase of about 2.6 ppm (currently 2.57 ppm for NOAA, 2.60 ppm for Scripps, with 2 1/2 weeks to go).

Closing the gap that Stephen mentioned in his last post wouldn't really change much in terms of the current year-to-year comparison, because 2022 also had a considerable gap around that time (caused by the eruption of the Mauna Loa volcano), comparing "no data" with "no data". Getting it back before next December would be nice though.

2022/23 had almost no increases at all during December and January -- an opportunity for 2023/24 to show some near-record weekly increases? We will see.

[kiwichick16]

thanks Ren  ....great work    ......happy hols ......see you next year

[Stephan]

A day earlier than usual (Christmas?) NOAA published the latest weekly Mauna Loa CO₂ average.

Week beginning on December 17, 2023:     422.24 ppm
Weekly value from 1 year ago:                   419.05 ppm
Weekly value from 10 years ago:                397.72 ppm
Last updated: December 23, 2023

Although the daily averages slowly drop from the upper level they have jumped onto (see my last posting) the annual increase is at 3.19 ppm, much higher than in the average of the last ten years (2.45 ppm/a). The houry values moved smoothly. A slight correction may occur; this "week" contained only 5 days. I'll keep you updated.

[Stephan]

The last weekly average of 2023 on Mauna Loa CO₂ is available.

Week beginning on December 24, 2023:     421.75 ppm
Weekly value from 1 year ago:                   419.41 ppm
Weekly value from 10 years ago:                397.53 ppm
Last updated: December 30, 2023

Once again the record is incomplete. From Dec 22 to Dec 25 they recorded no measurements. So this weekly average contains only four days. On these days the values were sufficiently stable.
The annual increase of 2.34 ppm is below the 10 y average of 2.42 ppm/a.

[Stephan]

The last month's average of Mauna Loa CO₂ for 2023 is available.

December 2023:       421.86 ppm
December 2022:       418.99 ppm
December 2013:       396.84 ppm
Last updated: Jan 05, 2024

Although six days are still missing in the record, we can assume this average is valid enough for a further analysis. The annual increase for December 2023 is at 2.87 ppm. This is higher than the 10 years' average of 2.50 ppm, and compared to previous years in the very upper part.
The increase rate is also higher than the expected rate which should be (linearly fitted 1958-2023) at 2.44 ppm/a.

I set an index of 100 [338.75 ppm] for 1980. December 2023 is at 124.5 compared to that index.

[gerontocrat]

& here is the graph plus one for global CO2 ppm to October 23.

As the years have gone by the linear fit for the upward trend becomes less and less viable.
The future trend though is dependent on 2 parameters; the trend in CO2 emissiions and the trend in CO2 capture by the land and ocean sinks. The first is largely under human control, the 2nd a mixture of envionmemtal reaction to human action and the impact of climate change.

[John_the_Younger]

Tamino offers some analysis and comments concerning CO2 acceleration on his WordPress blog.  A commenter on his blog suggested recent data looked (on a graph) like the upward acceleration had ended in recent years.  Do look at his analysis.  His conclusion:

it is possible, but by no means demonstrated, that the concentration of CO2 in our atmosphere is no longer accelerating upward; it is certainly still rising but perhaps no longer at an ever-increasing rate. It is also possible that it is still rising at an ever-increasing rate. My advice to readers in general, is to pay close attention in the next several years to the CO2 concentration data rather than the “emissions” data.

[Stephan]

This is my answer to this statement.
There is no stop in the ever increasing increase rate of CO₂ concentration.
Increase of increase rate = acceleration.

[John_the_Younger]

Tamino is referring to change over the last single decade - increases continue but acceleration may or may not be happening this decade.

[Renerpho]

Tamino is referring to change over the last single decade - increases continue but acceleration may or may not be happening this decade.

That's a true but meaningless statement, because it is true for every decade since the 1960s. Look at the data for any decade in isolation, and you don't see a clear trend. The year-to-year variability is too large.

[gerontocrat]

NOAA's data includes a de-seasonalised value. So I made a graph using that data.

Although the simple 12 month change is still highly variable, the CO2 ppm graph shows even more strongly a gradual acceleration in CO2 ppm, the 3 degree polynomial trend having an R2 value of 0.999.

That is not to say CO2 emissions when/if they are reduced might reduce the growth in CO2 ppm, BUT looking at the graph the big reduction in CO2 emissions during the COVID crisis has had little impact on the growth in CO2 ppm.

Which leaves us with the great unknown - the effectiveness of the land and ocean sinks.
 

[kiwichick16]

it would appear to be logical that the effectiveness of the sinks is declining............and emissions from wetlands and permafrost, for example, are increasing

https://www.arcticcirc.net/arcticnews/2022/8/4/thawing-permafrost-emissions-arctic-lakes-groundwater

[kassy]

The ocean sink declines as we warm the planet so there´s that.