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What will 2019's annual C02 concentration growth be over 2018?

≤ 2.0 ppm
0 (0%)
2.1 - 2.5 ppm
11 (33.3%)
2.5 - 2.9 ppm
17 (51.5%)
3.0 - 3.4 ppm
4 (12.1%)
≥ 3.5 ppm
1 (3%)

Total Members Voted: 33

Voting closed: February 02, 2019, 12:48:04 AM

Author Topic: 2019 Mauna Loa CO2 levels  (Read 8483 times)

crandles

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Re: 2019 Mauna Loa CO2 levels
« Reply #50 on: February 18, 2019, 12:22:10 AM »


Note the large variation of about 4ppm in last month compared to a year ago only having a range of around 2ppm.

Of course a 2.5ppm increase is something to be worried about. However, I suggest unusual increases of over 3ppm when the data is so variable is just unusually variable data and is quite likely to settle down. Yes, it might be suggestive of something bad, but if you are going to get extremely worried over this, then you are going to have to get used to being extremely worried about several different things at any one time.

crandles

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Re: 2019 Mauna Loa CO2 levels
« Reply #51 on: February 18, 2019, 01:27:37 PM »
What do you think it is supposed to mean?

We have had wild daily swings before, typically? high readings (or is it almost always? or even always) and they have always settled down again. We have an unusually large number: 6 (maybe 8?) of them in the last month or so compared with 1 in Feb 2018. I don't think we should let a few odd readings cause us to panic. If it settles 'up' to give consistent readings above 4ppm above the previous year then that would be genuine cause for increased concern and/or investigation.

I am expecting upward drift due to El Nino to values higher than 2.5ppm per year. 2.5ppm per year +- a bit with ENSO clearly gives us a GW problem certainly cause for concern. However, suggesting it could go to 5ppm sounded like inappropriate panic, and some keep calm and don't get carried away with a few wildly variable data points words seemed appropriate.

Environmentalists screaming the end of the world is nigh then it turns out to be a bit of variable data just makes the general population react by saying those environmentalists are always crying wolf and are increasingly likely to dismiss environmentalist views. So it is a bad idea and doesn't help the cause.

gerontocrat

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Re: 2019 Mauna Loa CO2 levels
« Reply #52 on: February 18, 2019, 02:46:24 PM »
Given an expected increase in CO2 emissions this year and a continued gradual reduction in the effectiveness of carbon sinks, a 2019 over 2018 increase of 3 ppm seems very much a possibility, even with a very modest El Nino.

Given existing CO2 emissions, a rise of 5 ppm on one year would require the carbon sinks to completely fail just like that, (which sends us to Douglas Adams' territory of infinite possibilities). The 5 ppm limit is basic arithmetic, the carbon sinks thing is basic science, e.g.s Henry's Law (oceans), photosynthesis (Land and Oceans).

In the longer-term, if and when CO2 emissions fall then the rate of increase in CO2 ppm will fall, as long as the carbon sinks work OK. However, even if emissions drop to say, 25% of today's emissions, CO2 ppm will continue to increase a bit every year, albeit much more slowly.

Armageddon is much more likely to be death by a thousand cuts
« Last Edit: February 18, 2019, 02:56:13 PM by gerontocrat »
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wolfpack513

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Re: 2019 Mauna Loa CO2 levels
« Reply #53 on: February 21, 2019, 07:49:53 AM »
I agree with gerontocrat.  A little early to be talking some huge 2019 growth rates.  3ppm definitely  looks possible considering ENSO the next 10 months.

Through the first 19 days I got NOAA February at 411.8 ppm.  Of course it will change the next 9 days but that's a 3.5 ppm growth rate.  Running 12-months is still only 2.25 ppm including that data.

Lurk

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Re: 2019 Mauna Loa CO2 levels
« Reply #54 on: February 23, 2019, 04:14:47 AM »
  Running 12-months is still only 2.25 ppm including that data.

ESRL had the 2018 growth at 2.68 ppm
https://www.esrl.noaa.gov/gmd/ccgg/trends/gr.html

How come there is such a large variation from that to the 12 months running mean? Is it a different kind of comparison? It seems odd to me that dropping the Jan-Feb first 6/7 weeks of 2018 would make such a large difference.

btw this current week with 5/7 days so far the growth is still high @ +3.21 ppm on last years comparable weekly data (2018 - 1-14  407.89) and the wild hourly/daily swings have settled down. 
https://www.esrl.noaa.gov/gmd/ccgg/trends/monthly.html
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Pmt111500

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Re: 2019 Mauna Loa CO2 levels
« Reply #55 on: February 23, 2019, 09:51:23 AM »
*uses trailing average*
*millions of deniers say it's fraudulent.*
Amateur observations of Sea Ice since 2003.

Lurk

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Re: 2019 Mauna Loa CO2 levels
« Reply #56 on: February 23, 2019, 05:47:20 PM »
It's not an argument that we went from a moderate La Niña to a weak El Niño in the last year. This of course impacts CO2. 

Could you explain the difference in how you describe a moderate la Nina vs the BOM calling it a "weak and short–lived La Niña had relatively little effect" ending in march 2018 http://www.bom.gov.au/climate/enso/wrap-up/archive/20180313.archive.shtml

and describing a weak El Nino in 2018 above when the BOM says it was neutral/watch/alert but as yet no El Nino is officially declared even now?
see http://www.bom.gov.au/climate/enso/wrap-up/archive.shtml

Is this because when they say "The tropical Pacific continues to meet some, but not all, El Niño criteria," is this what you mean by a weak El Nino?

Or does the US judge things differently than the BOM does? Is it a personal view or is it an official kind of view? I'm trying to understand these differences in "descriptions" and what's behind them, and how people here usually mean by such terms, thanks.
"You assist an unjust administration most effectively by obeying its orders and decrees. [...] A good person will resist an evil system with his whole soul. Disobedience of the laws of an evil state is therefore a duty."
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Lurk

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Re: 2019 Mauna Loa CO2 levels
« Reply #57 on: February 23, 2019, 05:59:06 PM »
*uses trailing average*
*millions of deniers say it's fraudulent.*

OK. So that's causing the difference with hard yoy avg. numbers. Looking at wolfpacks previous posts seems the "trailing/moving avg" was below 2ppm growth, moved above 2ppm, and in early Feb rose to 2.1 ppm, and at the 19th feb rose again to +2.25 ppm.

And he expects that to rise easily to 2.5 ppm during the year (all things being equal.) OK then.
"You assist an unjust administration most effectively by obeying its orders and decrees. [...] A good person will resist an evil system with his whole soul. Disobedience of the laws of an evil state is therefore a duty."
Mahatma Gandhi - Non-Violent Resistance

NeilT

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Re: 2019 Mauna Loa CO2 levels
« Reply #58 on: February 23, 2019, 07:33:09 PM »
Environmentalists screaming the end of the world is nigh then it turns out to be a bit of variable data just makes the general population react by saying those environmentalists are always crying wolf and are increasingly likely to dismiss environmentalist views. So it is a bad idea and doesn't help the cause.

Totally agree with that.  However the long term trend is up and continues up.  I talk about this on other threads but the point is we are a LONG way from Kyoto, yet the Global annual average continues to climb.

For the last 5 years the global average (based on ESRL NOOA growth stats), show an average of 2.5ppm.  OK 2018 will continue to adjust, the same site had 2015 at over 3ppm at this time of year and then adjusted it down to 2.91.

However the trend is very clear.  This is the first 5 years in the record where no year recorded less than 2ppm growth.  If it were not for 2011, we would be almost at a decade where no year recorded a growth value less than 2ppm.  As it is we'll probably have to wait till 2022 before we see that particular domino fall.  Probably around the time we see the first reported year with 3ppm.

Whilst caution is a very good stance to take, we have had accord and treaty after accord and treaty and the only result has been an acceleration in the growth of CO2 in the atmosphere.

The trend alone is, for some scientists, enough to produce very dire warnings.  Not only is CO2 still growing in the atmosphere, it is growing at an increasing rate.

Just when do you shout fire?  When you smell the smoke or when the flames are licking around your legs?  It is a problem because the population at large doesn't care about smoke and if you wait till the fire has really taken hold, then it's half past too late and nothing truly viable you can do about it.
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Shared Humanity

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Re: 2019 Mauna Loa CO2 levels
« Reply #59 on: March 04, 2019, 11:15:25 PM »
some nifty charts of atmospheric gases...

https://www.co2levels.org/

Lurk

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Re: 2019 Mauna Loa CO2 levels
« Reply #60 on: March 05, 2019, 10:51:04 AM »
My best guess for February 2019 MLO CO2 - must be out soon.

411.85 ppmv

about  +3.35 on Feb. 2018

.................

MLO CO2

February 2019:        411.75 ppm
February 2018:        408.32 ppm
Last updated: March 5, 2019

+3.43

https://www.esrl.noaa.gov/gmd/ccgg/trends/index.html
« Last Edit: March 05, 2019, 04:59:48 PM by Lurk »
"You assist an unjust administration most effectively by obeying its orders and decrees. [...] A good person will resist an evil system with his whole soul. Disobedience of the laws of an evil state is therefore a duty."
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rboyd

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Re: 2019 Mauna Loa CO2 levels
« Reply #61 on: March 05, 2019, 10:04:39 PM »
The annual (2018 versus 2017) numbers were updated for Mauna Loa and Global with the new months updates:

Mauna Loa: 2.86ppm
Global: 2.82ppm (based on November and December 2018, will be updated again when Jan and Feb numbers come in)

At the global level, the numbers so far this decade are now as below, with an average of 2.41 (vs. 2.02 the previous decade and 1.47 in the 1990s):

2011   1.70
2012   2.39
2013   2.41
2014   2.02
2015   2.91
2016   2.86
2017   2.13
2018   2.82

2018 was very close to the El Nino years of 2015 and 2016.

Stephan

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Re: 2019 Mauna Loa CO2 levels
« Reply #62 on: March 06, 2019, 10:47:56 PM »
...

2018 was very close to the El Nino years of 2015 and 2016.

And 2018 was not an El Niño Year...

dnem

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Re: 2019 Mauna Loa CO2 levels
« Reply #63 on: March 07, 2019, 05:33:45 PM »
some nifty charts of atmospheric gases...

https://www.co2levels.org/

The methane graph at that site shows a strong seasonal component but the annual rise is bimodal, peaking in the fall and spring after a small drop in winter.  I could make up some reasons why, but not sure.  Interesting.

gerontocrat

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Re: 2019 Mauna Loa CO2 levels
« Reply #64 on: March 07, 2019, 07:49:44 PM »

The methane graph at that site shows a strong seasonal component but the annual rise is bimodal, peaking in the fall and spring after a small drop in winter.  I could make up some reasons why, but not sure.  Interesting.
I think it is because the Northern hemisphere land area & therefore vegetation is so much greater than the Southern hemisphere

If you wish to revert to your second childhood, as I do (often unwillingly) on many days, then this link is for you...

https://www3.epa.gov/climatechange//kids/documents/carbon-through-the-seasons.pdf

CARBON THROUGH THE SEASONS
Introduction: 60–90 minutes
LEARNING OBJECTIVES:
Students will:
 Learn about the carbon cycle
 Understand how seasonal variations affect global atmospheric CO2 concentrations
 Understand how CO2 concentrations in the atmosphere are changing overall in recent decades
ADAPTED FROM:
National Oceanic and Atmospheric Administration (NOAA):
DESCRIPTION
In this lesson plan, students learn about the carbon cycle and understand how concentrations of carbon dioxide (CO2) in the Earth’s atmosphere vary as the seasons change. Students also learn that even with these seasonal variations, the overall amount of CO2 is increasing in the atmosphere as a result of people’s activities, which are changing the natural carbon cycle.

ps: Those thicko trump commissars trying to wreck the EPA seem to have missed the education pages.
« Last Edit: March 07, 2019, 08:09:37 PM by gerontocrat »
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dnem

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Re: 2019 Mauna Loa CO2 levels
« Reply #65 on: March 08, 2019, 01:16:25 PM »
No gerontocrat, that's why there is a seasonal up and down in the familiar Mauna Loa CO2 data.

If you look at the CH4 data, it also goes through a seasonal cycle, but it is quite different than the CO2 cycle.  It is lowest in the northern summer, generally bottoming out in July.  It then rises through the fall and hits a first peak in the early winter, then falls slightly during the northern midwinter, rises again in the late winter and early spring, then begins it bigger decent toward the next summer's minimum.  Almost every northern winter show this curious small mid-winter dip.

If I had to guess, it has something to with optimal temperatures for microbial metabolism.  Or maybe gas drilling and associated releases drops off during the cold mid-winter months? Or both? Or something else?

NeilT

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Re: 2019 Mauna Loa CO2 levels
« Reply #66 on: March 08, 2019, 07:48:48 PM »
At the global level, the numbers so far this decade are now as below, with an average of 2.41 (vs. 2.02 the previous decade and 1.47 in the 1990s):

However if you take the 7 years starting in 2012, the average is 2.5ppm.  2011 was, I am sure, impacted by the 2010 Eyjafjallajökull eruption with its impact on the stratosphere and air traffic in some of the most heavily travelled routes in the world.
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Ken Feldman

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Re: 2019 Mauna Loa CO2 levels
« Reply #67 on: March 08, 2019, 08:12:25 PM »
No gerontocrat, that's why there is a seasonal up and down in the familiar Mauna Loa CO2 data.

If you look at the CH4 data, it also goes through a seasonal cycle, but it is quite different than the CO2 cycle.  It is lowest in the northern summer, generally bottoming out in July.  It then rises through the fall and hits a first peak in the early winter, then falls slightly during the northern midwinter, rises again in the late winter and early spring, then begins it bigger decent toward the next summer's minimum.  Almost every northern winter show this curious small mid-winter dip.

If I had to guess, it has something to with optimal temperatures for microbial metabolism.  Or maybe gas drilling and associated releases drops off during the cold mid-winter months? Or both? Or something else?

It may be both.  The biggest natural component is wetlands, and tropical wetlands tend to dominate.  It may be tied to the Indian monsoon, rains in Indonesia, and other seasonal effects.

In the US, a large component of the fossil fuel extraction is fracking, and while the biggest fields are in Texas, there is a lot of oil drilling and fracking in the Bakken in Montana and North Dakota that goes through a slowdown due to severe weather in the winter.  There's also a lot of fracking for natural gas in Ohio, Pennsylvania and other northern states that may slow down in winter.  Russia has some large fields in Siberia, so those may also slow down when winter arrives.

gerontocrat

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Re: 2019 Mauna Loa CO2 levels
« Reply #68 on: March 08, 2019, 08:15:25 PM »
No gerontocrat, that's why there is a seasonal up and down in the familiar Mauna Loa CO2 data.

If you look at the CH4 data, it also goes through a seasonal cycle, but it is quite different than the CO2 cycle.  It is lowest in the northern summer, generally bottoming out in July.  It then rises through the fall and hits a first peak in the early winter, then falls slightly during the northern midwinter, rises again in the late winter and early spring, then begins it bigger decent toward the next summer's minimum.  Almost every northern winter show this curious small mid-winter dip.

If I had to guess, it has something to with optimal temperatures for microbial metabolism.  Or maybe gas drilling and associated releases drops off during the cold mid-winter months? Or both? Or something else?
It does seem to be at least partly a N / S hemisphere thing. The "winter" dip is apparently a S Hemisphere summer thing (lost the link but found this one)

https://royalsocietypublishing.org/doi/pdf/10.1098/rsta.2010.0341
The seasonal cycle is a convolution of seasonal cycles from Northern and Southern
Hemisphere sites driven by seasonality in reaction rates of CH4 with OH and emissions from some
sources (wetlands, rice production and biomass burning), and impacts of meteorology
"Para a Causa do Povo a Luta Continua!"
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Viggy

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Re: 2019 Mauna Loa CO2 levels
« Reply #69 on: March 09, 2019, 06:26:28 AM »

If I had to guess, it has something to with optimal temperatures for microbial metabolism.  Or maybe gas drilling and associated releases drops off during the cold mid-winter months? Or both? Or something else?

Throwing my guess in the hat, I would expect it would be related to the decomposition of organic matter in the NH that was buried under snow through fall and winter. This process would be happening over massive areas of land in extremely wet soils (as would be the case in spring) and drop off when summer ramps up.

Just quickly eyeballing it, 2014 spring seems to have one of the larger relative peaks in methane emissions - wouldn't that correlate to the year when NH snow cover had one of its largest extents?

Stephan

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Re: 2019 Mauna Loa CO2 levels
« Reply #70 on: March 17, 2019, 10:28:51 PM »
Another week with an increase of more than 3 ppm:
Week beginning on March 10, 2019:     412.16 ppm
Weekly value from 1 year ago:             409.02 ppm
Weekly value from 10 years ago:     388.71 ppm
The average increase of the last ten years is 2.35 ppm (which is already an awful lot if you go back 20 or 30 years)

Sam

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Re: 2019 Mauna Loa CO2 levels
« Reply #71 on: March 17, 2019, 10:54:31 PM »
Another week with an increase of more than 3 ppm:
Week beginning on March 10, 2019:     412.16 ppm
Weekly value from 1 year ago:             409.02 ppm
Weekly value from 10 years ago:     388.71 ppm
The average increase of the last ten years is 2.35 ppm (which is already an awful lot if you go back 20 or 30 years)

Remember as well that this does not consider the warming from the other warming gases. The total of those combined with global CO2 was estimated as being 526 ppm CO2(e) in 2016.

https://en.wikipedia.org/wiki/Carbon_dioxide_equivalent

Add to that the ~6 ppm CO2 rise since then, and the ~2 ppm CO2(e) rise in other warming gases, plus the annual variation to peak from average, and we are approaching peak annual CO2(e) of 540 ppm with average annual CO2(e) of ~ 532 ppm .  We are far above anything environmentally sustainable without catastrophic change for even short time periods. Forget 450 ppm, or even 500 ppm as a cap. We are going to blow through 550 ppm within about 5 years. We will make no significant reductions in that period. To the contrary, based on current trends, we will significantly add to the current emissions through that period. We are now less than 25 years (and possibly less than two decades) from blowing through 600 ppm CO2(e). That appears likely to occur about the years 2040-2042, possibly a bit sooner.

And if the clathrate releases from the arctic ocean accelerate from their current release rates, and/or the tundra releases of CO2 and methane increase, it may be even sooner than that.

My calculations of the forcing's puts us at about 535 ppm CO2(e) global now, and projects crossing 550 and 600 ppm CO2(e) in about the years 2022 and 2032 respectively (without added clathrate or tundra increases).

Sam

wdmn

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Re: 2019 Mauna Loa CO2 levels
« Reply #72 on: March 18, 2019, 01:04:45 AM »
Thanks for the reminder Sam.

I wonder is there a good figure for pre-industrial CO2eq?

rboyd

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Re: 2019 Mauna Loa CO2 levels
« Reply #73 on: March 18, 2019, 08:01:07 PM »
The calculation of CO2e assumes that the level of atmospheric methane will fall, as each methane molecule degrades in about 14 years. Our reality is that the level of atmospheric methane is increasing, as the degraded methane is being more than constantly replaced with new emissions. Therefore a better view of both current, and ongoing, warming would be the continuous CO2e for methane (about 100 times), rather than the 100 year one (the one used in official estimates - about 38 times) or even the 20 year one (about 86 times).

With this number for methane, the CO2e is well over 610ppm.Taking into account the offsetting effect of aerosols (the UN IPCC does this) we are over 550ppm.

In pre-industrial times there was very little of the non-CO2 gases, so the level of CO2 is a good proxy - about 280ppm. So we have already met the doubling of pre-industrial level of CO2e and are adding about another 5+ppm per year.

The level of aerosols is relatively constant as coal use growth has decelerated since mid decade and there is a lot more effort to scrub aerosols in China, while the atmospheric GHG levels (including methane) keep increasing. The result should be an acceleration in global average temperature increases.
« Last Edit: March 18, 2019, 08:08:24 PM by rboyd »

Stephan

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Re: 2019 Mauna Loa CO2 levels
« Reply #74 on: March 18, 2019, 10:37:35 PM »
The calculation of CO2e assumes that the level of atmospheric methane will fall, as each methane molecule degrades in about 14 years. Our reality is that the level of atmospheric methane is increasing, as the degraded methane is being more than constantly replaced with new emissions. [...]
I think this is an important point.
Always scientists come around with the "factor 30", claiming that methane is much shorter-lived than carbon dioxide. But the development of new methane seems to be endless, independent where its sources are exactly.
If one imagines the big "methane time bomb" ticking in N Siberia, N Canada and Alaska in the permafrost soil (and, of course, in the shallow seas of the Arctic Ocean close to Siberia) waiting to be liberated, the total Greenhouse Gas effect on future temperatures is much higher than today. Unfortunately it does not look like mankind is starting to slow down and reverse its CO2 emissions, so this all adds up to a bigger and bigger number...

wdmn

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Re: 2019 Mauna Loa CO2 levels
« Reply #75 on: March 18, 2019, 11:11:47 PM »
I don't quite follow you. CO2eq is a discrete measurement. IT shouldn't matter what value you assign to methane as long as you use the same value for both the baseline and current level.

This only matters if you reduce pre-industrial methane to zero, which I don't think should be done.

mitch

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Re: 2019 Mauna Loa CO2 levels
« Reply #76 on: March 18, 2019, 11:57:56 PM »
pre-industrial CH4 was about 700 ppb vs about 1800 ppb today:
https://earthobservatory.nasa.gov/features/MethaneMatters

One should be able to make a pre-industrial CO2e.

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Re: 2019 Mauna Loa CO2 levels
« Reply #77 on: March 19, 2019, 02:37:21 AM »
The only number I have found is 280ppm CO2 for pre-industrial (in the UN IPCC materials), I cannot find a preindustrial CO2e number anywhere. A calculation would also need assumptions on N2O, which was about 270 ppb in 1800.

https://www.eea.europa.eu/data-and-maps/daviz/atmospheric-concentration-of-carbon-dioxide-3#tab-chart_5_filters=%7B%22rowFilters%22%3A%7B%7D%3B%22columnFilters%22%3A%7B%22pre_config_polutant%22%3A%5B%22N2O%20(ppb)%22%5D%7D%7D


Sam

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Re: 2019 Mauna Loa CO2 levels
« Reply #78 on: March 19, 2019, 03:07:20 AM »
The only number I have found is 280ppm CO2 for pre-industrial (in the UN IPCC materials), I cannot find a preindustrial CO2e number anywhere. A calculation would also need assumptions on N2O, which was about 270 ppb in 1800.

https://www.eea.europa.eu/data-and-maps/daviz/atmospheric-concentration-of-carbon-dioxide-3#tab-chart_5_filters=%7B%22rowFilters%22%3A%7B%7D%3B%22columnFilters%22%3A%7B%22pre_config_polutant%22%3A%5B%22N2O%20(ppb)%22%5D%7D%7D

After a bit of digging, I found the following suggested values:

CO2: 278 ppm
CH4: 722 ppb
Stratospheric Water: ??
N20: 270 ppb
Tropospheric Ozone: 270 ppb
CF4: 10-7 ppt
C2F6: 3.47x10-6 ppt

Using Forcing factors (W/m2/ppb) of:
CO2: 0.014
CH4: 0.037
N2O: 0.12
H2O: 0.011
O3:   0.02
CF4: 0.25
C2F6: 0.09

This results in a total forcing of 3,956 and reverses to a CO2(e) of 282.56 ppm, or 4.56 ppm above the CO2 background level. Stratospheric water may change that a little.  So, about 4.5 ppm above the CO2 level.

The most commonly used methods use a logarithmic ratioing to the preindustrial levels. It is cleaner and likely better not to do it that way.

Worse though is that the reality is so much more complex than the simple methods suggest. The various gases exist in differing quantities at different altitudes, latitudes, and seasons, rather than as a homogeneous picture through the entire column. The IR reflections and refractions occur in differing frequency bands with very complex overlaps. Sun angles, latitude, seasonality, cloud decks and more all play roles. Etc... To actually model all of that would take an extremely sophisticated model and a supercomputer to evaluate. It isn't something we can easily do using computers at home.

Still, the simple models do seem to fairly accurately portray the situation as a smeared average. Do not take the number of digits in the result as significant. The result is only a likely central value, lacking any attempt at an error estimate.

Still, the calculation is instructive.  Where we were at CO2 of about 278 ppm and CO2(e) of about 282.5 ppm.  We are today at about 414 ppm (Mauna Loa today) CO2 and circa 540 ppm CO2(e). That represents increases since pre-industrial of about 136 ppm CO2 and 258 ppm CO2(e).

That is of course - assuming that I haven't blundered badly somewhere in the data or math.  Please check the results before using them. Assuming that I haven't seriously erred in the calculation, that suggests a starkly different consideration of the conditions using the CO2 versus CO2(e) numbers. Using the CO2(e) values, it suggests we will reach a doubling of the background in 8-9 years. Again, please check my math - especially if you have access to better models or approaches to perform the calculation.

Sam


« Last Edit: March 19, 2019, 03:20:30 AM by Sam »

Lurk

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Re: 2019 Mauna Loa CO2 levels
« Reply #79 on: March 19, 2019, 05:12:27 AM »


Good overview imho. Would be best to stick with the global numbers though not MLO @414 ppm

December 2018:        409.36 ppm
https://www.esrl.noaa.gov/gmd/ccgg/trends/global.html

Maybe a April/May max of 411.5 +/- this year

It doesn't change the underlying take away message or the truth of it.
"You assist an unjust administration most effectively by obeying its orders and decrees. [...] A good person will resist an evil system with his whole soul. Disobedience of the laws of an evil state is therefore a duty."
Mahatma Gandhi - Non-Violent Resistance

oren

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Re: 2019 Mauna Loa CO2 levels
« Reply #80 on: March 19, 2019, 10:07:31 AM »
After a bit of digging, I found the following suggested values:

CO2: 278 ppm
CH4: 722 ppb
Stratospheric Water: ??
N20: 270 ppb
Tropospheric Ozone: 270 ppb
CF4: 10-7 ppt
C2F6: 3.47x10-6 ppt

Using Forcing factors (W/m2/ppb) of:
CO2: 0.014
CH4: 0.037
N2O: 0.12
H2O: 0.011
O3:   0.02
CF4: 0.25
C2F6: 0.09

This results in a total forcing of 3,956 and reverses to a CO2(e) of 282.56 ppm, or 4.56 ppm above the CO2 background level. Stratospheric water may change that a little.  So, about 4.5 ppm above the CO2 level.

The most commonly used methods use a logarithmic ratioing to the preindustrial levels. It is cleaner and likely better not to do it that way.
Thanks for the calculation, however your end result does not settle with my intuition. The other gases can't be contributing so little, given that they were quite abundant in the pre-industrial atmosphere as well. If I am not mistaken (this is not my line of expertise, if such even exists) your w/m2/ppb numbers are ppm, not ppb, (or mW, not W) and the number for methane should be 10 times higher. I also have suspicions that the O3 and N2O numbers are much lower than they should be.
(I am looking at the table here and making rough calculations.)

Lurk

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Re: 2019 Mauna Loa CO2 levels
« Reply #81 on: March 19, 2019, 04:48:43 PM »
"You assist an unjust administration most effectively by obeying its orders and decrees. [...] A good person will resist an evil system with his whole soul. Disobedience of the laws of an evil state is therefore a duty."
Mahatma Gandhi - Non-Violent Resistance