Carbon pollution and solution

I’ve said I try to stay out of climate change debates, but I’m trying to learn more.  I’m taking a retired-person class from a retired person well-known in climate change circles, Steven Running (google him), and I thought I’d share a couple of his many slides that I think say a lot about the role of forests in saving the planet from dangerously unpredictable climate changes.

For any doubters, the first slide shows the the role of human activities in raising the world’s temperature.  It’s basically all about us, and CO2 is the biggest problem.  The second slide shows the role of land  in CO2 emissions and sequestration.  The point is that when the atmosphere and the ocean must absorb the new emissions it causes the serious problems we are starting to see today.  That means we have to attack the three parts of this equation we have control over, the human sources of emissions and land-based carbon sequestration.  I suspect the answer is mostly “reduce the use of carbon fuels,” but maximizing the carbon content of land is going to be important, too.  Regarding forests, he has already said that planting trees can’t be done at the necessary scale, and cultivated biofuels are a net carbon source (though converting organic residue to energy would help).

13 thoughts on “Carbon pollution and solution”

  1. Jon, thank you for posting this information and Dr. Running’s graphics.

    Another natural source of atmospheric cooling is the SO2 (sulfur dioxide) emitted during volcanic activity. After reading an article about the number of recent volcanic eruptions, I began wondering about the cooling effect of that volcanic SO2 and if there is a quantifiable, long- or short-term relationship seen in atmospheric temperatures in the areas around the eruptions.

    Another issue I wondered about was wether or not the mandated reductions of SO2 emissions by the passage of the Clear Air Act, and the subsequent reduction of its atmospheric cooling effect, can be quantified in relation to the increase in global warming.

    Are either of these issues covered in your “retired person” class?

    Sadly, human behavior has caused the Earth’s closed system to be so far off-kilter that it seems as if the more we try to put things right, the further off-center we go.

    Thanks again.

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  2. Jon,,
    I don’t know if Running “missed” it, or you did , or both?, but human population size and growth are the foundation of all of this, and it is, obviously, a subject that paralyzes most people. That should not be the case however for environmental activists and scientists; sadly, it seems to be.

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  3. Jon, as a person who’s been following climate science since the 80’s, I think it’s a great deal more complicated than the graphs show. For one thing, after decades of research, our understanding of what happens in the atmosphere and oceans is not complete (and is complex and contested).

    For another it’s hard to think that folks know what land use was back in 1750 around the world (first graph) …

    “Regarding forests, he has already said that planting trees can’t be done at the necessary scale, and cultivated biofuels are a net carbon source (though converting organic residue to energy would help).”

    But planting trees can be done, and contribute something (not enough to solve the problem but so what?). Biofuels can be done with different ones having different impacts given different assumptions.

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  4. I suggest that there is more “natural” climate change than is shown in the chart, Radiative Forcing Caused by Human Activities since 1750. That year, 1750, is commonly cited as the peak (or valley, if you prefer) of the Little Ice Age, before which glaciers had been expanding worldwide. Most of the ice in the formerly vast glaciers in Glacier Bay, Alaska, melted between 1750 and 1900. Glaciers in Europe and Greenland have been retreating since 1750. What was the cause of the melting during that period? Surely human activity played a very small role.

    I’d like to hear what Dr. Running has to say about this.

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    • I asked about the choice of start dates and he said it’s mostly about the available data (which would have been limited by an ice age), and something like “statisticians who work with this stuff are alert to the possible use and effect of bias based on choices like this.” I didn’t specifically ask him about non-human causes of melting, but he had another slide that showed CO2 levels back a half million years, which I have added above. I would assume that temperature changes follow these cycles and are caused by the “natural” factors (solar radiation) varying in some way.

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  5. A. As you might expect, some think it is difficult to separate natural from anthropogenic sources of change.
    Many folks I’ve read says it’s hard to do. Here’s a recent example.
    https://www.nature.com/articles/s41612-019-0075-7

    One of their problems is that you need long timespans to detect the fingerprint of GHG (see reference to the recent slowdown in the paper). Meanwhile right now the data from 100 years ago is not as great as might be hoped in terms of consistency with locations and measurements of today so that makes it hard to pick up those long-term signals. At least that’s what I’ve been able to make of this literature.

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  6. Sue – Interestingly, the slide right after the first one above compared carbon from humans, solar radiation and volcanoes (maybe there wasn’t room on the first slide?). If the increase due to solar radiation is +0.05 W/m2, the decrease due to volcanoes is -0.10 W/m2. So like an order of magnitude different from what humans are adding. I assume SO2 would be included in the “other” gases in the <0.5 range, so any reduction would not be very large, and then the Clean Air Act is only the U. S. (I assume increased coal burning in places like China and India has more than offset any gains in the U.S.) I'll listen for more.

    Brian – So far, population has been discussed in the context of food security and whether climate change will mean we can't feed the population under different scenarios up to 11 billion people. I have assumed that same growth rate is built into the carbon production of various climate projections. We're moving into the discussion of "solutions," so I'll see if/how population comes up.

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  7. The operating principle in all the laws that apply is use “the best available science.” They don’t say irrefutable or unquestioned. I can’t judge whether this science is that, but it comes pretty highly credentialed. I have to question how much energy we should be putting into debating how much less than perfect it is when the actions we can and should take in response are not going to be sensitive to that information. (In an interesting coincidence, Dr. Running also used the slide that Matthew Koehler posted here: https://forestpolicypub.com/2020/01/28/climate-science-voyage-of-discovery-iii-history-of-the-rcp-8-5-controversy/)

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  8. Jon, I think determining what is the “best available science” is more difficult a) the more studies there are and b) the more complicated the problem.

    I agree that the actions might not be all that sensitive to specific scenarios. So I propose the solution as (1) Let’s reduce CO2 and other GHG production, and (where not otherwise problematic) increase soil and plant sequestration.

    So we all agree! or perhaps the devil is in the details.. now given that, what is the “best science” about the cost and impacts of specific ways of ameliorating the problem? It depends.. on what disciplines are involved. What scale you look at.. and so on.

    One thing though, if we accept (1) as a given, we are out of the world where climate modelers are experts, and into the world of different technologies for energy and CCS and land management. And we can say “experts should be exploring all of the above”..and sure enough, they are, and we still have no controversy.

    And for forests in the US, we are actually the experts on how they grow and can easily append carbon calculations.

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    • I agree that the most important question is “what is the “best science” about the cost and impacts of specific ways of ameliorating the problem” as well as the relative benefits. (Though this shouldn’t be read as “do nothing until we have this information.”) With regard to national forests, that science should be used in long-term strategic forest planning. It’s there that the Forest Service has to take a position on what it thinks the role of a national forest should be based on this science. Here’s a couple of recent examples of relevant forest science I’ve seen:

      “A study by Oregon State University researchers has identified forests in the western United States that should be preserved for their potential to mitigate climate change through carbon sequestration, as well as to enhance biodiversity.” (Includes a priority map.)
      https://phys.org/news/2019-12-forests-crucial-climate-mitigation-biodiversity.html

      “According to the environmental group’s analysis of (British Columbia) provincial data, logging puts 42 million tonnes of carbon emissions into the atmosphere per year, as well as another 26 million tonnes that can’t be recaptured for at least 13 years, while newly planted trees mature enough to absorb the additional carbon.”
      https://www.cbc.ca/news/canada/british-columbia/b-c-s-clear-cut-forests-are-dead-zones-emitting-more-greenhouse-gases-than-they-absorb-new-report-finds-1.5398660

      The Forest Service must acknowledge or dispute these implications for forests in the northwest when it makes its decisions.

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      • I don’t think that would be difficult. for the second study I’d start with the IPCC report and see what the different assumptions were.

        The first is more concerning…

        “The five-year study supported by the U.S. Department of Agriculture’s National Institute of Food and Agriculture identified, and targeted for preservation, forests with high carbon sequestration potential, low vulnerability to drought, fire and beetles, and high biodiversity value.”

        This sounds like something that could really benefit from PNS concepts and an extended peer community.. prioritizing areas in Colorado for some combo of carbon, different measures of biodiversity, etc. with local and practitioner knowledge and input. And then there wildlife corridors…

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  9. I think of forests as surface, cycling carbon. They burn or die and are released and refixed. When we pump up and burn old, relatively non-cycling carbon, we provide too much. With climate change, trees can not possibly absorb enough of that carbon, in part due to heat stress in existing forest, and in part because of more large fires. The absorption of atmospheric carbon by surface vegetation can buffer things, but it still keeps all that carbon on the surface, where it will release again.
    I do think energy production from slash is a good idea, to reduce fuels, to reduce pumped, subsurface carbon use, and because surface fuel will burn eventually anyway. Efficiency, reduction, and using surface fuels are all part of the equation.

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  10. So here’s the take-home about managing forests for climate. There was one slide that addressed carbon credits that said “Foresters use best management practices.” There was no discussion of what those might be. There was another presenter who is a building contractor who is an expert on low-carbon building technology, and he did view engineered wood products as being helpful as mitigation through substitution for more energy intensive materials. We didn’t have any discussion of the tradeoff involved with reducing forests below an optimum carbon sequestration rotation to create wood products. (I would assume those who have set up carbon markets have made decisions on carbon credit values based on these kinds of tradeoffs, but I’ll leave that research to others.)

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