In recent weeks, a new study by researchers at ETH Zurich has hit the headlines worldwide (Bastin et al. 2019). It is about trees. The researchers asked themselves the question: how much carbon could we store if we planted trees everywhere in the world where the land is not already used for agriculture or cities? Since the leaves of trees extract carbon in the form of carbon dioxide – CO2 – from the air and then release the oxygen – O2 – again, this is a great climate protection measure. The researchers estimated 200 billion tons of carbon could be stored in this way – provided we plant over a trillion trees.
The media impact of the new study was mainly based on the statement in the ETH press release that planting trees could offset two thirds of the man-made CO2 increase in the atmosphere to date. To be able to largely compensate for the consequences of more than two centuries of industrial development with such a simple and hardly controversial measure – that sounds like a dream! And it was immediately welcomed by those who still dream of climate mitigation that doesn’t hurt anyone.
Unfortunately, it’s also too good to be true. Because apples are compared to oranges and important feedbacks in the Earth system are forgotten. With a few basic facts about the CO2 increase in our atmosphere this is easy to understand. Mankind is currently blowing 11 billion tonnes of carbon (gigatonnes C, abbreviated GtC) into the air every year in the form of CO2 – and the trend is rising. These 11 GtC correspond to 40 gigatons of CO2, because the CO2molecule is 3.7 times heavier than only the C atom. Since 1850, the total has been 640 GtC – of which 31 % is land use (mostly deforestation), 67 % fossil energy and 2 % other sources. All these figures are from the Global Carbon Project, an international research consortium dedicated to the monitoring of greenhouse gases.
The result is that the amount of CO2 in our air has risen by half and is thus higher than it has been for at least 3 million years (Willeit et al. 2019). This is the main reason for the ongoing global warming. The greenhouse effect of CO2 has been known since the 19th century; it is physically understood and completely undisputed in science.
But: this CO2 increase in the air is only equivalent to a total of just under 300 GtC, although we emitted 640 GtC! This means that, fortunately, only less than half of our emissions remained in the atmosphere, the rest was absorbed by oceans and forests. Which incidentally proves that the CO2 increase in the atmosphere was caused entirely by humans. The additional CO2 does not come from the ocean or anywhere else from nature. The opposite is true: the natural Earth system absorbs part of our CO2 burden from the atmosphere.
Conversely, this also means that if we extract 200 GtC from the atmosphere, the amount in the atmosphere does not decrease by 200 GtC, but by much less, because oceans and forests also buffer this. This, too, has already been examined in more detail in the scientific literature. Jones et al. 2016 found that the amount of carbon removed from the atmosphere amounts to only 60% or less of the negative emissions, when these are implemented on the background of a mitigation scenario (RCP2.6).
We can also compare the “negative emissions” from tree planting to our other emissions. The 200 GtC would be less than one third of the 640 GtC total emissions, not two thirds. And the authors of the new study say that it would take fifty to one hundred years for the thousand billion trees to store 200 GtC – an average of 2 to 4 GtC per year, compared to our current emissions of 11 GtC per year. That’s about one-fifth to one-third – and this proportion will decrease if emissions continue to grow. This sounds quite different from the prospect of solving two-thirds of the climate problem with trees. And precisely because reforestation takes a very long time, it should be taboo today to cut down mature, species-rich forests, which are large carbon reservoirs and a valuable treasure trove of biological diversity.
There is another problem that the authors do not mention: a considerable part of the lands eligible for planting are in the far north in Alaska, Canada, Finland and Siberia. Although it is possible to store carbon there with trees, albeit very slowly, this would be counterproductive for the climate. For in snowy regions, forests are much darker than snow-covered unwooded areas. While the latter reflect a lot of solar radiation back into space, the forests absorb it and thus increase global warming instead of reducing it (Bala et al. 2007, Perugini et al. 2017). And increased regional warming of the Arctic permafrost areas in particular would be a terrible mistake: permafrost contains more carbon than all trees on earth together, around 1,400 GtC. We’d be fools to wake this sleeping giant.
And there are other question marks. Using high-resolution satellite maps and Google Earth, the researchers have analyzed where there is a suitable place for forests where none is currently growing, leaving out farmland and cities. With the help of machine learning technology, natural areas around the world were evaluated to determine the climate and soil conditions under which forests can thrive. The free and suitable land areas found in this way amount to 1.8 billion hectares – as much as the combined area of China and the USA.
But for many of these areas, there are probably good reasons why there is currently no forest. Often they are simply grazing lands – the authors respond that they have only assumed loose tree cover there, which could even be beneficial for grazing animals. The Dutch or Irish pastures would then resemble a savannah. Nevertheless, there are likely to be considerable obstacles of very different kinds on many of these areas, which are not apparent from the bird’s-eye view of the satellites. The authors of the study also write that it is unclear how much of the areas found would actually be available for planting.
Therefore, I’d still consider it optimistic to assume that half of the calculated theoretical planting potential can be realized in practice. Then we’re talking of 1-2 GtC of negative emissions per year. But that is precisely what we will need urgently in the future. The current global CO2 emissions can be reduced by 80-90 % through transforming our energy, heating and transport systems – but there will remain a rest that will be hard get rid of (e.g. from agriculture, industrial processes and long-haul flights) and that we will have to offset in order to stabilize the global climate.
The study by the ETH researchers has another important result that has hardly been reported. Without effective climate protection, progressive warming will lead to a massive loss of existing forest cover, especially in the tropics. At the same time, the models are not yet able to make reliable statements on how forests can cope with new extremes, fire, thawing permafrost, insects, fungi and diseases in a changing climate.
The massive planting of trees worldwide is therefore a project that we should tackle quickly. We should not do that with monocultures but carefully, close to nature and sustainably, in order to reap various additional benefits of forests on local climate, biodiversity, water cycle and even as a food source. But we must not fall for illusions about how many billions of tons of CO2 this will take out of the atmosphere. And certainly not for the illusion that this will buy us time before abandoning fossil fuel use. On the contrary, we need a rapid end to fossil energy use precisely because we want to preserve the world’s existing forests.
Links
Would a large-scale tree restoration effort stop climate change? Forest expert Marcus Lindner from EFI points to the fires in Russia and the success story in China.
How to erase 100 years of carbon emissions? Plant trees-lots of them. National Geographic shows the importance of indigenous peoples as guardians of the forest.
Restoring forests as a means to many ends The commentary in Science on the Bastin study revolves around the question of how sustainable reforestation can be designed with multiple benefits beyond mere carbon storage.
Tree planting ‘has mind-blowing potential’ to tackle climate crisis Guardian
Analysis: How ‘natural climate solutions’ can reduce the need for BECCS Last year Carbon Brief prepared this analysis of how much carbon mitigation potential may be expected from “green” solutions like tree planting or biochar.
In the last hundred entries in a comment thread on “Can-planting-trees-save-our-climate? there’s little to glean but copious copy from someone mysteriously calling himself Engineer-Poet whose contributions don’t show much evidence of aptitude as either, lay commentary on DNA repair, racial IQ, and simplistic economic assertions about the grid. Any connection to planting trees remains opaque. Isn’t that what the open threads are for? In the interest of breadth of appeal for your site, here’s one more request for a bit more assertive moderation from the moderators.
One more thought. Before the nuclear industry is able to forcefully scale back decades of standards for radiation exposure they will have to address the question of just how much exposure should be allowable, how different people will respond to a uniform and ever accumulating blanket of radiation (which will remain radioactive for potentially millions of years). e.g. infants, the elderly, the infirm. Also how nature will respond, from song birds to worms to sea and air bacteria, to fish, to plants etc. To the biosphere as a whole. Remember, every plant would now be freely emitting and I doubt that they would all be keeping accurate track. Yes hormesis would be a really handy way for the nuke business to dispose of its waste. A very polluting plan indeed. What other industry has such license? Well ep implies in 176 that we should throw out all kinds of standards.
The arrogance and bravado is stunning.
Oh, what about if you don’t want any extra radiation, or want any extra on your land? Will you have the right or the ability to refuse?
It’s a big, ugly Pandora’s box you’re proposing to open up for everyone just to help a giant, dirty business. Are you sure you want your name on that? Ep, of course, would be delighted. You seemed more thoughtful.
#201 Richard Creager, also for Engineer-Poet,
I usually get after people to be more on-topic but the FR thread where that discussion belongs was not open. Now it is.
Engineer-Poet, in case you are actually going to try to respond to my last comment, please do it on Forced Responses.
Why pick trees? Why not pick something with a high tolerance to poor soils and reasonably low water requirements. Bamboo for instance. Pick a clumping not running variety. Clear cut each growth cycle. Pyrolyse, generate power and charcoal. Bury the charcoal to improve the soil quality over time in conjunction with manure and repeat. Do do in conjunctions with bunds for added dedesertification. Repeat until soil stabilised. Then plant something usefully productive fruit trees for instance and move on. Bamboo is just grass on steroids, make use of it. You get better soils, more productive land a local power source and eventually food. Along the way you get to sequester more carbon.
Addendum. The bund method will also let you control runoff and establish better water management long term. Bamboo, itself grows almost anywhere. The only continent without a native species is Europe, but it does most definitely grow there. If we ignore desertification and look more to Europe you could easily take brown field sites and put them to work. Note. It can be quite invasive, so some care has to be taken when selecting an optimal variety. But this can easily be done.
Re: 159, Yes radiation triggers an immune reaction, but then so will a splinter. At least with a splinter there’s not much chance for developing a hideous cancer from it. With radiation, it might be a hormetic aid in some cases due to stimulating that immune response, but there’s also the very real potential for getting cancer, which most of medical literature has been saying. Not a great bargain if you asked me.
First, sorry for the long hiatus. Life happened.
Quoth nigelj:
Good enough for UNSCEAR even though the results contradict the LNT party line. There were obviously previous studies as well, as noted in para. 15.
My understanding is that there WERE no studies, and the “food pyramid” contradicted the known data at the time. But there was no alternate media then to get the word out.
You know, I am 1000% for that and have been saying so for years. We should be doing all of this stuff over again, with bigger populations and tons and tons of detailed side studies looking at telomere length, mutation rates, gene activity measurements, Hayflick limit, in-vitro studies of mutation and gene activity in monkey and human cell cultures, all at a range of dose rates… and that’s just what my non-biologist head can think of right now. Give me the national credit card and you’ll have a heap of guys on this stuff as soon as they get their grant applications in.
It does beg the question of why this hasn’t been done over the past 61 years, though, doesn’t it? I can think of a very good explanation: the LNT party line is VERY important to certain powerful interests, and they made certain that nobody ever got a grant to study this phenomenon again.
If that was the case, we’d have a huge public-health discovery hiding there in Colorado. (Obviously we do either way.) We should most certainly work at uncovering the cause and mechanisms.
The part I want everyone to read is perhaps half a page total, and a fair chunk of that is a table of results. Here’s the link again, start at p. 30 para. 14 (they’re numbered) and about halfway down the first column of the next page. Everyone should have time for that.
Quoth zebra:
And I told you that you really can’t, because electricity is not like trinkets or meat at the supermarket or even like real estate. The physics of electric generators and the AC grid itself impose non-market limits. Pols decided that they could just ignore all of that, and that’s not going to work.
<snort> Contempt for people acting stupidly is not panic, and I write almost all of this from scratch (digging up links as I go).
What you are not getting is that the way you want your “market” to work has externalities. HUGE externalities. These externalities are not charged back to those who create them, or even priced very well. These externalities have names like ramp rate, reactive power, AFC, spinning reserve and minimum operating level. Fail to respect them and you have no market because your grid goes down. A blacked-out grid serves no one.
Let me go back over one externality of “renewables”, which is ramp rates and minimum operating levels. I’ll use the GE H-class combined cycle plant as an example. The 9HA-02 has a rated CC output of 1680 MW(e), a minimum load of 15% and ramp rate of 176 MW/min. If you want to shut it down, it takes on the order of 30 minutes to bring it back on-line… IF you expend the energy to keep it hot. Cold starting no doubt takes much longer.
That 9HA has a heat rate of 5598 kJ/kg of fuel (LHV), presumably at full rated power (efficiency will decrease at lower power levels but the documentation does not give heat rate/efficiency at lower or minimum power). Methane has a LHV of 50.0 MJ/kg, so the 9HA will burn 0.1120 kg per kWh and emit 308 gCO2 out the stack in the process.
Limitations:
1. You can’t go below 15% output without shutting down. Once shut down, you can’t be certain of having power again for 30 minutes.
2. Even assuming that the heat rate remains at 5598 kJ/kWh at much lower outputs (and it won’t, it’ll go much higher) you’re still emitting hundreds of grams of CO2 per kWh.
3. Given the requirements for reactive power and spinning reserve, you may not be ABLE to shut down and keep the grid in operation.
4. Starting burns fuel but does not generate power, so you have to add emissions from that.
5. At perhaps 15% capacity factor from PV, you’re mostly running on NG and still have net emissions of well over 200 gCO2/kWh.
Remember that the need is to get total emissions down by at least 80%, and the electric sector may have to get to zero to allow space for other sectors which can’t trim as much and still stay in operation. Conclusion: even with the best CCGT technology on the planet, gas + renewables falls far short of the decarbonization we need from the electric sector.
Now let’s consider zero-emission nuclear. The AP1000 can only ramp at 5%/minute and that only over 90% of the fuel cycle. Suppose your “market” takes bids once per hour. Are you going to expect 100% of your bid-for amount at the minute the auction closes, or are you willing to wait a goodly fraction of an hour before output has ramped up far enough to serve you? Do you expect someone to have a battery available to provide that on-demand power whenever you want it… and how are you going to pay to finance that battery, for its inverter/charger system, and its depreciation and insurance against things like fires? Where does THAT appear on your electric bill?
Where’s your “market” when you can’t buy your neighbor’s PV because the backup CCGT is a must-run plant generating reactive power to keep the grid from blacking out, and it is already at its minimum operating power?
Do you get an idea just how much of a mess you’re dealing with here, and how much messier you want to make it? None of this is simple. LISTEN TO THE ENGINEERS, THEY KNOW WHEREOF THEY SPEAK.
Quoth Michael D. Sweet:
Please, there’s a hyphen in my nom de guerre. Use it, would you?
I do not say that generating energy with renewables is impossible; obviously it is, as we are doing it. What I claim is that it is impossible to rely on them to get emissions down far enough to stabilize the climate (we’ve been trying since the Carter administration and we are going backwards; fossil fuel consumption continues to increase). What we need is 24/7 energy that can replace everything fossil fuel does. Until we get it we can probably use wind and PV to offset some fuel use here and there, but it isn’t going to do nearly as much good as its advocates claim and we should be compensating it purely on the carbon savings and charging it back for its externalities, not on whatever imaginary benefits it has. If we do that, there will be a whole lot less of it and a lot more of other things. That is not as it is now, but as it should be.
Also re: Michael D. Sweet:
I’m obviously getting tired today, because I forgot my main point. Germany is projected to have spent €500+ billion on the Energiewende by 2025, yet its carbon reductions have stalled out and it will not meet its original 2020 targets. This sum would be enough to build a fleet of EPRs sufficient to decarbonize the vast bulk of Germany’s electric consumption plus a modest reserve. Given this, every cent spent on renewables instead of nuclear was a net detriment to the entire planet.
EngineerPoet said:
Not crude oil, as it’s on its last legs. The USA is the number one producer but that’s because of highly leveraged investment in shale oil extraction via fracking. If the selling price isn’t high enough and a payout is expected, the players will start exiting
https://oilprice.com/Energy/Energy-General/Oil-Price-Correction-Triggers-Shale-Meltdown.html
Quoth Al Bundy:
First, if you can’t bother to hotlink my comment in reference, you are literally quoting out of context.
Second, a claim of “90-100%” requires data to back it up, not just anecdotes. That data has to include evidence of the mode of causation. I’m not going to buy and read a book only to find that it doesn’t have any proof of what it claims to be true. Life is too damn short. If you want me to do that you are going to have to pay me. $50/hour is a good start.
The “Red Forest” was killed by acute radiation exposure from I-131. I-131 has a half-life of 8.01 days so is extremely “hot”. It is also extremely GONE, passing 100 half-lives more than 30 years ago.
Whatever ecological impact remains in the region of the Red Forest is due to the destruction of topsoil as part of the “remediation” effort which bulldozed it into graves. As your reference notes:
I’d take an extended stroll in the Red Forest without hesitation.
No picture at that link shows leaf litter. There is fallen grass, which is green and thus fairly fresh. Old dead grass is brown even when not irradiated.
I don’t trust books. Show me the peer-reviewed papers of those scientists, or GTFO.
Gamma is what Cs-137 does. Learn something about radionuclides.
What would you expect of children who were told they were going to die, and probably handled accordingly? Look what happened to the medically fragile Fukushima evacuees. Those needing careful medical attention often died before reaching any sort of shelter, because their needs in transit were ignored. Now consider years of psychological stress on innocent children, and consequent inattention to their other needs.
EP @208, I’m certain there were studies in around the 1950s finding saturated fats were bad for health, but there were only a small number and with benefit of hindsight they were poor quality studies. My understanding is the new wisdom is that saturated animal fats are neither good or bad for health.
However I still wont be going crazy with the butter. When it comes to diet, science is still a bit of a mess. Humans are essentially omnivores, evolved with a varied diet, so anyone who wants to suggest extreme diets of any type are going to have to present compelling proof to me. I think the safest bet is the Mediterranean diet as it mixes a range of foods in some sort of balance, and humans are omnivores.
Quoth “John” (just how well does the vice squad know you, “John”? Are you on a first-name basis with the decoys?):
Let me tell you something:
I am 1000% for that. And I am for designating the exposure levels where the humans, flora and fauna receive high natural background radiation without detectable harm as 100% safe without reservation, and working from there. We do not need exposure levels “ALARA” (As Low As Reasonably Achieveable). We need AHARS (As High As Reasonably Safe) for workers, and AHAPS (As High As Proven Safe) for the public. We and the planet are LITERALLY being killed by fears of what is harmless.
If we can pull this comment thread back to the original post….
I think large scale tree planting is an important part of the “all of the above” concept. There is no question that trees can sequester a significant amount of carbon, with minimal input (save regular watering until new plantings are well established) and at low cost. No carbon capture technology is scalable and deployable in the immediate future, why not use trees?
An important point that hasn’t been made in any of the comments is that the study erred by choosing to NOT include urban areas Not only do cities offer significant space for tree planting, the impact of these trees on GHG emissions is far greater than those planted in rural or undeveloped areas. Shade trees planted in urban areas combat the urban heat island effect and reduce energy consumption, thus avoiding new future GHG emissions. When planted in sufficient numbers, these trees can cause neighborhood scale cooling.
How significant are urban forests in combating AGW? The urban forests in Lawrence, MA, a small, post-industrial gateway city, sequester over 553 thousand pounds of CO2 annually. These trees avoid an nearly equal amount, over 523 thousand pounds of new CO2 emissions every year.
https://drive.google.com/file/d/12gaL_Ry0Z9PQ5BBFNobcOuxLdEWFPt9k/view
Lawrence has just 26% tree cover and can accommodate thousands of additional trees, over 1500 new trees have been planted since 2016 alone. Urban communities are on the front lines of combatting AGW and urban forests are an important part of that fight.
Tennis Lilly @216 — Thank you for the reminder. I lived near Lawrence for the summer of 1956. I imagine that it looks rather better now.
In addition to the cooling and carbon dioxide benefits you described, people feel better living under some trees, as especially opposed to just grass landscaping. By all means plant more seedlings.
#209 engineer-poet,
I have responded to you on the Forced Responses thread, which is set aside for this kind of discussion. It would be polite for you to move over there, since there are people who want to continue discussing tree-planting without scrolling through all our unrelated comments.
EP,
Wow! Zero comprehension, zero analysis, and zero value! Trifecta, dude!
Again, get to a library so your cheap a** can read a valuable book for free.
Please try to actually turn on that mediocre 3SD brain
(If I were saddled with such a handicap I’d…
E-P 208: the LNT party line is VERY important to certain powerful interests, and they made certain that nobody ever got a grant to study this phenomenon again.
BPL: Maybe the Jews are behind it. Or the Vatican. I have it! The Illuminati!
EP, #211–
Nope. Doesn’t follow in the first place, and is grotesquely untrue in the second.
The decision to denuclearize was independent of expenditure on renewables. Hence, had the money spent on renewables gone to some other purpose, what we would have seen would have been a significant *increase* in German emissions. That’s the true counterfactual case.
Also, it is not true that German emissions have “plateaued”. There was a record low emissions total in 2018, as can be seen here:
https://www.cleanenergywire.org/factsheets/germanys-greenhouse-gas-emissions-and-climate-targets
It’s pretty clear, I think, that German emissions continue to drop despite the (IMO) unnecessary handicap of the accelerated phase out of their existing nuclear fleet. (In this connection, it is true that they are quite likely to miss their 2020 target, as the Ministry of Energy projects. Although it’s interesting that if the observed decline from 2017 to 2018 were to obtain for another two years, they’d only miss it by one year.)
Be that as it may, there’s another way in which German support for renewables–which goes back well before the advent of the Energiewende in 2010–has been a boon, not a detriment, to the planet, and that is that it has been an important factor in scaling up deployment of wind and solar, and thereby of driving the startling reductions in cost that have been observed. The resulting explosion of RE capacity has been global, and it has manifested in the continuing decline of coal as an industry.
I’ll say it again: I think that we should support existing nuclear capacity, except where it is either unsafe due to age or other circumstances or grossly uneconomic, and I think we should support nuclear research into SMRs and such, as this may be important in the future. But the backbone of the near-future grid is going to be RE, because it’s just a whole lot faster and more affordable to build.
With a ~3x difference in LCOE working against them, new builds of existing nuclear tech just have too high an opportunity cost.
ep, “(just how well does the vice squad know you, “John”? Are you on a first-name basis with the decoys?)”
Not sure what thats meant to imply. Who exactly is “engineer poet”? Anyway…
“I am for designating the exposure levels where the humans, flora and fauna receive high natural background radiation without detectable harm as 100% safe without reservation, and working from there.”
So your starting point is blatant bias. Ok.
“We do not need exposure levels “ALARA” (As Low As Reasonably Achieveable). We need AHARS (As High As Reasonably Safe) for workers, and AHAPS (As High As Proven Safe) for the public. We and the planet are LITERALLY being killed by fears of what is harmless.”
Oh I agree there are lots of unfounded fears. They should be overturned when possible. But pretending that you’re somehow above all that superstition, unfounded (great), but also founded fears – where there’s a scientific consensus, where there’s significant evidence – is a dangerous reverse intellectualism. Let’s apply that thinking to other pollutants as well, shall we. How about how much, say, mercury a coal plant, or other polluter can emit? How much 2,4-D a farmer can apply to his fields that will affect the downward community and land? How much formaldehyde a mobile home manufacturer can have in their walls? How many new, novel and wholly untested chemicals, which appear every year, should be allowed etc. After all, it’s for the greater good, the economy (oh, and, of course, the businesses bottom line) right? You did say your’e a believer in hormesis, as per your comments in 178, not just radiation, but lots of other toxins as well. Would this be because you believe their regulation would be bad for business? I’m just wondering, do you happen to be affiliated with a rightwing think tank?
https://www.epa.gov/sites/production/files/2015-09/documents/priority-pollutant-list-epa.pdf
What you don’t seem to be getting is that the radioactive pollution from the nuke industry will not be the sole source of radiation the workers and the public receives. There are many others (though not as pervasive, omnipresent, and potentially hazardous and long lasting as the n-plant’s pollution) particularly medical and radon/thoron, industrial, exposure to smokers etc. There’s also radiation from other terrestrial sources and from space.
You appear to want to start from the upper limit for nuclear plants. All others would be added on top of that.
Again, the only ones this is fair to is nuclear. All others assume the risks without choice. And that’s fine by you. Given this lack of concern and honesty on the industry’s part, it’s no wonder they aren’t trusted.
This Is Zero Hour is the indigenous-to-America, or to-New-York, youth group. The leadership is authentically 16-17 and the relationship between Greta Thunberg and them is an incredible story. They will be among those looking out for her in New York. “This (G. Thunberg) is genius. We’ve been really supportive of each other’s work.” –Jamie Margolin, This Is Zero Hour.
I really hope a long-game journalist/historian or two are on the story.
G. Thunberg arrives New York Tuesday. Close to it now. Livetracker plus social transmits: FOLLOW ALL LIVE ON THE MAP, with social transmits:
https://tracker.borisherrmannracing.com/
FOLLOW ALL WITHOUT THE MAP:
https://twitter.com/borisherrmann
https://twitter.com/GretaThunberg
https://twitter.com/thisiszerohour?lang=en
FAQs:
https://www.borisherrmannracing.com/news/frequently-asked-questions-on-the-transat-with-greta-thunberg/
https://www.borisherrmannracing.com/news/the-new-solbian-solar-system-on-board-malizia/