The volcanic eruption of Mount Pinatubo in June 1991 led to a significant cooling of the tropical ocean surface due to the cloud belt formed by the eruption. This cooling resulted in a temporary reduction in the rate of increase of atmospheric carbon dioxide (CO2) concentrations.
Despite ongoing human CO2 emissions and natural sources of CO2, the cooling effect caused by the volcanic aerosols led to a rapid absorption of CO2 by the ocean. At least that is an important conclusion of a study by my friend and chemist, Bud Bromley.
Bud’s study demonstrates that the oceans have a tremendous capacity to absorb large amounts of CO2 – much more than is emitted by humans.
This absorption, after the eruption of Mount Pinatubo, was followed by a rapid recovery and acceleration of CO2 levels once the cooling effect dissipated.
I’m going to be interviewing Bud Bromley next month, specifically at 6pm Hawai’i time on Thursday, 24th April (2pm Brisbane-time the next day, Friday April 25th). This will be the fourth zoom meeting in my series Towards a New Theory of Climate Change. If you would like to be a part of this Webinar please register at:
https://us02web.zoom.us/webinar/register/WN_QrVa8XEzSPS_GvUWnXkX0Q
You will then be sent a confirmation email with a link that you will need to join the webinar, so please file the confirmation email carefully.
Bud lives in Hawai’i and is a chemist by training. He blogs at https://budbromley.blog/
Bud concluded from this Pinatubo study that human CO2 emissions are not causing the increase in atmospheric CO2. The amount of human CO2 emissions is negligible, less than a rounding error, considering the total carbon budget of the Earth.
To be sure, Bud is of the considered opinion that contrary to what you have probably read, heard or been taught, the addition of human produced CO2 to the atmosphere by burning natural gas, oil and coal does not increase the global CO2 concentration of the atmosphere. Nor will sequestration of CO2 reduce CO2 concentration in the atmosphere.
According to Bud, the CO2 concentration in the atmosphere today is the same as it would be if humans never existed. Ouch.
Life goes on in the oceans, and at coral reefs the fish and the corals are more affected by the sea tides that are a consequence of the gravitational pull of the Sun and the Moon. As we develop a new theory of climate change it is important that we have words for describing important processes. Let me suggest that the sea tides be considered external drivers unaffected by occasional events such as volcanic eruptions; such is the nature of external drivers. Then there are internal state variables such as temperature that are affected by volcanic eruptions – and there are feedback mechanisms such that the rate of increase in the atmospheric concentration of carbon dioxide is hardly affected.
The photograph of me underwater is from Britomart reef in November 2020. I noticed at this reef, as I have been noticing across the bay at the coral reefs fringing Great Keppel Island, that with coral bleaching there can be an expansion in the range of the sea anemones and their clown fish.
Thanks Ferdinand.
If we have four on the panel for this discussion that could work, so you and either Greg or Dave.
I would probably choose Ivan Kennedy as my 'partner' in this discussion, if we have a panel with four.
I would be keen to cohost this with C02 Coalition so there was some technical support for me behind the scenes. At the moment I am doing the webinars entirely on my own, and it can be difficult to see who has their 'hand up' and/or which mic from the audience needs to be muted, etcetera.
I am keen to discuss this more, and perhaps the key person for this discussion is Greg Wrightstone.
I am also keen to potentially run it as per my last webinar which was over three different time zones by having three consecutive sessions. Last Saturday we had a 12noon session eastern Australian time, then a 11am London time, then a 3pm Houston time.
Saturdays suit me, so I would suggest Saturday 12th July as a best date. That is the end of the week that I have suggested. :-).
Dear Jennifer,
I have registered for the webinar with Bud Bromley for 24/25 April...
And the week of 7th July still is empty and get reserved by now...
I suppose Greg and/or Dave will weight in too...
I don't think that there is any differentiation in reactions for "human" or "natural" CO2, except for some small differences in isotopic composition (which "marks" the origin...).
The main point is that natural emissions were more or less in equilibrium with natural sinks and still show a surprisingly small variability from year to year of not more than +/- 1.5 ppmv around an over 100 ppmv up going trend in the period since 1958.
Even with extreme events like the 1991 Pinatubo and the 1998 and next large El Niño's, human emissions in each year were larger than what was measured as increase in the atmosphere with only a few borderline exceptions and over 200 ppmv one-way human emissions over the same period...
As Greg already said: the height of the natural fluxes within a year is not important at all for what happens in the atmosphere, only the net difference in natural ins and outs is important at the end of the year...
Best regards,
Ferdinand
Hi Ferdinand
Thanks so much for this detailed reply, and in three parts. This is very much appreciated. :-).
There is a lot to unpack here. And I will do so over the next little while.
Perhaps a fundamental different in how we approach this issue is the extent to which it is realistic to consider human versus natural emissions as different. As I see it whether from natural or human sources, carbon dioxide is involved in chemical and biological processes near the Earth's surface. Carbon dioxide is being continually produced and destroyed naturally near the Earth's surface and size of this flux dwarfs human emissions.
Because carbon dioxide is so reactive (potentially quickly forming carbonic acid, then bicarbonate depending on temperature and more in the sea surface layer) I consider it important to think both in terms of the carbon budget and also carbon dioxide cycling.
There is fundamental disagreement then in terms of our conclusions, with my conclusion that the ocean is a net source of carbon dioxide at this point in the cycle.
I am keen to discuss this all with you in more detail.
I will be interviewing Bud Bromley on 24th/25th April (depending on your time zone), and we will be discussing Henry's Law and more. This discussion is open to anyone who first registers, and the link is here: https://us02web.zoom.us/webinar/register/WN_QrVa8XEzSPS_GvUWnXkX0Q
At this stage, I am definitely more in agreement with Bud's assessment, we tend to come from a similar starting point and make similar assumptions. Bud though, focuses very much, in fact almost exclusively on patterns of C02 change, while like you, I also consider temperature. I am as interested in seasonal change in temperature, as well as long term anomalies, that I see you have incorporated into the first chart of your important report as published by the C02 Coalition.
I would be keen to have a discussion about all of this by way of a webinar that all and any can register for, and participate in. My plan is to have a webinar very month and at the moment I already have guests lined up, but not confirmed, for May and also June. Would it be possible to interview you as part of this series early July? Could I suggest sometime the week beginning Monday 7th July. I am more than happy to make this event something cohosted with the C02 Coalition. The format so far, that seems to be working, is one hour for discussion/interview and then another hour for questions from guests/participants. So all up, I would be asking for two hours of your time early July. Of course, it always ends up taking time to prepare for such events, etcetera.
Kind regards, Jennifer
Something not mentioned in the above comments is the quantity of CO2 that having been dissolved in sea water is then combined with calcium/magnesium ions in the presence of free iron ions to form mainly calcium carbonate within sea creatures such as plankton or carbonate ooliths to eventually give rise to limestone deposits. Such deposits are probably the largest depositary of formerly atmospheric CO2 in the world.
*****
Thanks Richard, You raise an important point. It is the case that I have attempted to draw attention in an above comment, that I will republish here, as perhaps following your plain English comment this information will be better appreciated/heard/noticed.
A seasonal model showing changes in sea surface temperatures can affect ocean chemistry and in turn atmospheric concentrations of carbon dioxide is detailed in Kennedy et al. that can be accessed here: https://www.mdpi.com/2673-7264/2/4/28
Not behind a paywall. :-).
And the abstract reads: Seasonal oscillations in the partial pressure of carbon dioxide (pCO2) in the Earth’s atmosphere, stronger in northern latitudes, are assumed to show that terrestrial photosynthesis exceeds respiration in summer, reducing the pCO2 in air but increasing its value in winter when respiration exceeds photosynthesis. We disagree, proposing that variation in the temperature of the surface mixing zone of seawater also reversibly regulates the pCO2 in air as a non-equilibrium process between air and seawater. We predict by thermal modelling that carbonate (CO32−) concentration in the surface mixed layer seawater declines in winter by conversion to bicarbonate with CaCO3 (calcite or aragonite) becoming more soluble and, proportional to the fall of temperature, calcite decalcifying more strongly, allowing more CO2 emission to air. Paradoxically, the increasing CO2 concentration in seawater favoring photosynthesis peaking in mid-summer declines simultaneously in autumn and early winter, forced by boundary layer fugacity into phase transfer to the atmosphere, supporting peak atmospheric pCO2 by late winter. These physico-chemical processes reverse in late winter and spring as seawater warms favoring calcification, fugacity forcing CO2 from the atmosphere as bicarbonate declines and carbonate increases, augmenting suspended calcite particles by several percent. Our numerical computation predicts that the larger range of thermal fluctuations in the northern hemisphere could reversibly favor absorption from air of more than one mole of CO2 per square meter in summer with calcite formation potentially augmenting shallow limestone reefs, despite falling pH, if there is a trend for increasing seawater temperature. Another assumption we challenge is that upwelling and advection from deeper water is the sole cause of increases in dissolved inorganic carbon (DIC) and alkalinity in surface waters, even in the southern hemisphere. Instead, some calcite dissolution is favored as water temperature falls near the surface. Standard enthalpy analysis of key DIC reactions indicates why this oscillation is more obvious in the northern hemisphere with seasonal variations in water temperature (ca. 7.1 °C) being almost twice those in the southern hemisphere (ca. 4.7 °C) with a greater depth of the surface mixing zone of seawater in the southern oceans. Questions remain regarding the relative rates of biotic and abiotic inorganic precipitation and dissolution of CaCO3 in the mixing zone. In summary, rapid biogenic calcification is favored by summer photosynthesis, but slower abiotic calcification is also more likely in warmer water. We conclude that the relative significance of terrestrial biotic and seawater abiotic processes in seawater on the seasonal oscillation in the atmosphere can only be assessed by direct seasonal measurements in seawater.
Cheers, Jennifer
Jennifer: I believe that Ferdinand Engelbeen has sumitted a detailed reponse concerning the numbers.
The bottom line is that natural atmospheric CO2 sources are many multiples of that from human emissions... BUT and it is a big BUT... That has nothing to do with the increase in atmospheric CO2 because, while the sources from nature (including oceans) are huge, the sink into the oceans is even bigger, meaning that both the biosphere and the oceans are net sinks. This is documented with a slight decrease in ocean pH and an increase in PCO2.
The gross amount is immaterial. It is the NET that matters.
You have to be able to explain what happens to the 50% of human emissions that don't show up in the atmosphere.
Bud Bromley asked if we do agree with the video where Henry's law is explained...
Of course we do agree with the effect of Henry's law. We do not agree with the figures of Bud, which are far beyond what Henry's law says...
Henry's law only is applicable to pure, dissolved CO2 in water, not to bicarbonates and carbonates.
In fresh water dissolved CO2 is 99% of all inorganic carbon species, only 1% of bicarbonate and practically no carbonates are found.
A CO2 doubling in the atmosphere thus gives a CO2 doubling in fresh water per Henry's law.
In sea water, pure, dissolved CO2 is only 1% of all inorganic carbon species. Bicarbonates form 90% and carbonates 9% in seawater.
If CO2 in the atmosphere doubles, also pure, dissolved CO2 in seawater doubles per Henry's law, but bicarbonates and carbonates don't double, as the reactions of CO2 to bicarbonate and further to carbonate set H+ free, lowering the pH and thus pushing the reactions back to free CO2.
The net result is some 10% increase of DIC in seawater for a 100% increase of CO2 in the atmosphere. That is called the Revelle/buffer factor.
Still 10 times more CO2 is dissolved in seawater than in fresh water...
As the supposed inorganic carbon content of the sea surface layer is around 1000 PgC, not much away from the 890 PgC of the atmosphere (1 PgC = 1 GtC), and the average pCO2 of the oceans is about 7 μatm below the pCO2 of the atmosphere, the ocean surface is only a small sink for the CO2 increase in the atmosphere en certainly not the cause of the CO2 increase in the atmosphere.
See further the formula of Takahashi for the temperature influence and the overall atmosphere-ocean surface CO2 fluxes as compiled by Feely etal.:
https://www.pmel.noaa.gov/pubs/outstand/feel2331/maps.shtml
Dear Jennifer,
Then we have your:
"A feature of the annual increase in CO2 as ppmv is this seasonal oscillation."
and further:
"it could be that ocean warming causes ocean ‘acidification’ that causes more degassing of CO2. I am keen to open up discussion on this point."
So let's discuss that point...
One can distinguish the origin of huge CO2 changes by looking at the simultaneous δ13C changes.
CO2 from ocean origin has a higher δ13C level (at -6.4 per mil after sea surface - atmosphere transfer and back) than the atmosphere (at currently below -8 per mil), thus CO2 release from the oceans increases the δ13C level of the atmosphere. Reverse with more uptake, but anyway CO2 changes and δ13C changes parallel each other.
CO2 from the biosphere (and fossil CO2) has a much lower δ13C level than the atmosphere (at -24 per mil), thus any significant release from the biosphere will give a drop in δ13C in the atmosphere, but reverse with more uptake. Anyway: CO2 changes and δ13C changes oppose each other.
Both the seasonal changes as the year-by-year changes show that the biosphere is the main cause of the changes. Here for the seasonal changes:
https://www.ferdinand-engelbeen.be/klimaat/klim_img/seasonal_CO2_d13C_MLO_BRW.jpg
and here for the year-by-year changes:
https://www.ferdinand-engelbeen.be/klimaat/klim_img/temp_dco2_d13C_mlo.jpg
In both cases, the biosphere is certainly the dominant cause of the changes, but in opposite direction for seasonal and year-by-year changes!
Over the seasons: CO2 drops with increasing temperatures (about 5 ppmv/K), year-by-year CO2 increases with increasing temperatures (about 3.5 ppmv/K).
Over very long periods (decennia to multi-millennia) the oceans were the main cause of the CO2 changes, as can be seen in hardly any change in δ13C level over the past 800,000 years, despite huge changes in temperature, until humans started to bring lots of CO2 with very low δ13C level into the atmosphere:
https://www.ferdinand-engelbeen.be/klimaat/klim_img/co2_d13C_lgm_cur.png
Even if every single fossil CO2 molecule was catched by the next available tree, that doesn't make a difference for the increase in mass of CO2 in the atmosphere: that is at the cost of a natural molecule of CO2 that would have been catched instead.
An instant doubling of CO2 in the atmosphere doesn't give an instant doubling of CO2 uptake by plants or oceans, that needs time to grow more stems and plants or to reach the deep oceans...
Moreover, the δ13C levels in atmosphere and oceans show already that over 10% CO2 in the atmosphere comes from fossil fuel origin and over 6% in the ocean surface. Also in plants there is a drop (depending of plant type) and in the deep oceans, where the waters (mainly in the N.E. Atlantic) sink into the deep...
Hope that this discussion helps to understand the quite difficult difference in result between a small one-way addition and the effect of huge natural cycles...
Best regards,
Ferdinand
Dear Jennifer,
Here follows a reaction on the possibility that the oceans are the cause of the recent rise of CO2 in the atmosphere...
1. Over the past 800,000 years, we have quite good direct measurements of CO2 in the ancient atmospheres in ice cores and of Antarctic proxy temperatures by δD and δ18O measurements of the surrounding ice. That gives a ratio of about 8 ppmv/K over the past 800,000 years for Antarctic temperatures or around 16 ppmv/K for global temperatures due to the polar amplification.
2. Takahashi studied the influence of temperature on a lot (near one million) seawater samples and formulated the change as:
(pCO2)seawater at Tnew = (pCO2)seawater at Told x EXP[0.0423 x (Tnew – Told)]
That gives for the (probable) SST increase since the Little Ice Age some 13 ppmv increase of CO2, or if one doesn't thrust the temperature proxies: less than 10 ppmv CO2 increase since 1958 (no matter what you take as "real" SST increase)...
That is all.
It simply is impossible that the sea surface temperature is the cause of the current increase, as that would imply that the CO2/T ratio suddenly increased from around 16 ppmv/K to over 100 ppmv/K over the past 67 years. Bud Bormley is completely mistaken on that item. The more that humans released over 200 ppmv one-way over the same time frame...
Then the ocean pH and DIC.
Theoretically, it is possible that a lot of undersea volcanoes released a lot of SO2, dropping the pH of the ocean surface and releasing a lot of CO2 into the atmosphere.
If that was the case, then DIC (CO2 + bicarbonates + carbonates) would drop in the ocean surface.
In reality, the measurements show a (small) drop in pH, but a significant increase in DIC, what is only possible if the net CO2 flux was from the atmosphere into the oceans, not reverse...
Dear Jennifer,
In the past, David Burton and I have had a lot of discussions with Bud Bromley and others with a "not our CO2" point of view, without much result...
That lead to the work we made, together with Renee Hannon (ice core specialist), of an overview that we made for the CO2 coalition:
https://osf.io/preprints/osf/het6n_v1
Besides that, I have made a PowerPoint slide presentation for a discussion with Koutsoyiannis and others in workshop in Athens last September for the pro's and con's of the human cause:
https://www.ferdinand-engelbeen.be/klimaat/klim_img/on_the_co2_residence_time.ppsx
Where a lot of process details were presented.
About your question for the quantities involved:
Using rounded figures of the IPCC (for 2020):
Human emissions: 10 PgC/year on-way in. Land use changes not included.
Oceans: 90 PgC/year in and out.
Biosphere: 120 PgC/year in and out.
The IPCC figures are based on (diurnal, seasonal) CO2, O2, δ13C and DIC measurements with large margins of error (+/- 30%), except for human emissions, which are -0 to +10% (due to the human nature to avoid taxes...) and the increase in the atmosphere which is +/- 5%.
To begin with: the difference between human emissions and the other inputs:
The human input is one-way: 100% gets in the atmosphere and nothing is removed by humans (even reforestation in some countries is dwarfed by land use changes in other countries). All other natural inputs are more than compensated by natural outputs. Both the oceans and the biosphere are net sinks for CO2...
So where then is the imbalance?
For the biosphere:
One need to split the uptake/release of the biosphere into diurnal and seasonal cycles:
While plants take some 120 PgC/year out of the atmosphere during the day and mostly in spring/summer, some 60 PgC/year is already released at night by plant respiration and ground bacteria near the roots. The other 60 PgC is released from fallen leaves and other material all year and especially in fall/winter.
The overall unbalance is around 2.5 PgC/year more uptake than release, based on the oxygen balance (and δ13C changes) over a year:
https://tildesites.bowdoin.edu/~mbattle/papers_posters_and_talks/BenderGBC2005.pdf
The biosphere certainly is a net sink for CO2, the earth is greening...
Then we have the oceans:
Again there is a huge difference between the ocean surface and the deep oceans: the first is in direct contact with the atmosphere and exchanges CO2 and other stuff (like O2) with a half life time of less than a year.
The IPCC assumes that the deep oceans are completely isolated from the atmosphere by the ocean surface chemical and physical constraints, but that is not the case: some 40 PgC/year sinks with the deep ocean water circulation directly into the deep and only 50 PgC/year gets from surface to atmosphere and back from the ocean surface.
The overall imbalance for the ocean surface waters is only 0.5 PgC/year, based on the change in DIC (dissolved inorganic carbon) measured at 6 stations:
https://tos.org/oceanography/assets/docs/27-1_bates.pdf
Table 2 and Figure 3.
The small uptake is caused by the Revelle/buffer factor: the ocean surface 100% of pure, dissolved CO2 for a 100% change in the atmosphere (per Henry's law), but only 10% for a change in total inorganic carbon (DIC: CO2 + bicarbonates + carbonates).
To close the carbon mass balance, the difference between what is measured in the atmosphere and human emissions must go into the deep oceans, as all other probable sinks are either too small or too slow...
That then pushes about 2.0 PgC/year extra into the deep oceans.
Overall unbalance:
10 PgC/year human emissions into the atmosphere.
2.5 PgC/year into the biosphere.
0.5 PgC/year into the ocean surface.
2.0 PgC/year into the deep oceans.
5.0 PgC/year (temporarily) remaining in the atmosphere.
That is the overall imbalance per year for the current (2020) atmosphere...
Thanks Danny.
I will have to unpack the ocean chemistry, and the extent to which atmospheric concentrations are affected by changes in sea surface temperatures, to explain why it is important, in my opinion, to consider atmospheric ppm separately from total reservoir. They measure different things.
In short, it is my hypothesis, that ppmv (what is actually measured at Mauna Loa) will be affected by sea surface temperature via changes in pH. Meanwhile, because the total reservoir in the ocean is so much greater it will be RELATIVELY hardly affected at all.
To answer your final question:
Q. Danny to Jenn: Do you accept the statement of Ferdinand Engelbeen et al. that the oceans are a net sink?
Answers:
If you mean a net sink for human emissions, I will have to answer NO. I suspect most of the human emissions of C02 are very quickly 'breathed in' by northern hemisphere forests adjacent to all the factories and cities, at least in the northern hemisphere. :-).
If you mean overall are the oceans a net sink for C02, I would have to again reply NO. Because overall the data from various locations including Mauna Loa shows very clearly that there is net degassing of carbon dioxide from the Earth's oceans since at least 1958.
Following my logic and this has nothing whatsoever to do with human emissions that, in my opinion, are insignificant relative to natural processes including natural fluxes that are very much affected by ocean upwellings, phytoplankton blooms, and sea surface temperatures. :-).
Following my logic from very beginning to very end (and so far I haven't got to explain the end bit in necessary detail) increasing atmospheric concentrations of carbon dioxide can be explained entirely by ocean degassing and as a consequence of the current natural cycle of warming that has dominated ocean circulation since at least 1958 but perhaps not much before then. :-).
I would guess that my position if very similar to a minority of other scientists notably Demetris Koutsoyiannis. I suspect I go somewhat further in my attribution of natural processes than Bud Bromley and Ivan Kennedy, but perhaps not.
Thanks for reading this far.
It has been an opportunity for me to drop some of my thoughts, that are already part of my framework for a new theory of climate resilience. :-).
This note was edited once, immediately after posting, in particular for formatting and to add 'in my opinion' a few times through the text.