Fewer cows, more trees and bioenergy

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Combatting global warming will require major changes in land use, a new climate change report says. One important change could be decreasing the amount of land used to produce livestock—which means that people would have to eat less meat.

Francesco Cherubini likes to ask his Industrial Ecology students what's the most common use of land today, and nearly all of them get the answer wrong.

"The correct answer is grazing land," Cherubini, a professor and director of NTNU's Industrial Ecology Programme. "Today we are using nearly half of the land on our planet to feed animals and not people."

Cherubini has more than an academic interest in this question—and what the answer means. He's one of the lead authors of the IPCC's new special report, released today, on Climate Change and Land, and was the only author from a Norwegian-based institution.

He formally handed the report over to Ellen Hambro, Director General of the Norwegian Environment Agency, and Ola Elvestuen, Minister of Climate and Environment on Thursday, when the IPCC released the report in Geneva.

The IPCC describes the report as an "assessment of the latest scientific knowledge about climate change, desertification, land degradation, sustainable land management, , and greenhouse gas fluxes in terrestrial ecosystems."

The report also looks at the interrelationships between different competing land uses and how these could affect future potential climate outcomes.

Cherubini says the report offers policymakers yet more reasons to act on curbing greenhouse gas emissions and taking action to make sure that plays a positive role in solving the climate problem—and acting sooner rather than later.

"Land management is key for us to achieve our climate management objectives," he said. "But we have competing land uses and limited land resources: we rely on land for animal feed, food, fibres and timber, and we need to preserve biodiversity and all the ecosystem services that land provides. And on top of that we have climate change."

The new report is an analysis of more than 7000 publications and looks at possible future scenarios to suggest the kinds of changes that need to happen under different socioeconomic situations, assuming society tries to limit warming to 1.5 C.

Using these scenarios allowed Cherubini and his co-authors to see what kinds of actions would need to be taken—and when—to keep warming to the 1.5 C goal.

For example, if society changes to a more plant-based diet, more efficient agriculture and food production systems and embraces new cleaner energy technologies, this will make land available for key climate change mitigation measures such as growing more trees or bioenergy crops.

"We'll need a lot of land for change mitigation," he said, no matter what.

Even in the most sustainable future scenario that will allow us to meet the 1.5-degree goal, the amount of forest land needed to soak up CO2 by the end of this century will top out at about 7.5 million km2, or roughly the size of Australia, Cherubini said.

In contrast, when the researchers looked at a more resource-intensive future scenario, they found it will be necessary to devote 7.5 million km2 of land to bioenergy crops as early as 2050 to keep warming below 1.5 C. Another important component of using bioenergy under this scenario, he said, is that it will have to be coupled with more and earlier carbon capture and storage.

The IPCC Special Report on Climate Change and Land contains many actions that can be implemented now to increase the chances that we can meet the 1.5 C goal, says Francesco Cherubini, one of the report's lead authors and head of the Industrial Ecology Programme at the Norwegian University of Science and Technology. Credit: Synnøve Aune, NTNU

However, under all the scenarios, land has to be used for both bioenergy and for forest growth, as well as for food production and other human uses, Cherubini said.

"Bioenergy needs to be put in place with all the other mitigation options to achieve the 1.5 C goal," he said. "We shouldn't think of this as a competition for land between forest and energy crops. We need both."

When Cherubini and his colleagues looked at the different scenarios, they were also able to assess how these different futures would affect different parts of the globe in terms of food insecurity, land degradation and other negative impacts.

This allowed the scientists to provide an assessment of "how we do this in the best way possible," Cherubini said. "We have a choice in the kinds of risks we will experience based on what kind of socioeconomic development takes place."

If society doesn't develop in a sustainable way, he said the risk of land degradation and food insecurity is much higher, especially in developing countries. Additionally, mitigation efforts have to be designed carefully to make sure they have a beneficial effect, he said.

One example of how a well-intentioned programme can have unwanted or unanticipated effects is China's "Grain for Green" programme, a massive tree-planting effort.

Under all the social development scenarios, planting trees to soak up carbon is important to curb global warming. It's also a tool used to reverse soil erosion , which is one reason why China undertook its programme.

But in the case of China's efforts, at least some of the trees they planted were non-native. That meant that the trees took up more water than a native tree would have, and have increased the risks of causing other problems, such as water shortages, Cherubini said.

One aspect of the new report that has generated the most attention is the suggestion that societies move to more vegetarian diets.

"Balanced diets, featuring plant-based foods, such as those based on coarse grains, legumes, fruits and vegetables, nuts and seeds, and animal-sourced food produced in resilient, sustainable and low-GHG emission systems, present major opportunities for adaptation and mitigation while generating significant cobenefits in terms of human health," the summary for policymakers says.

Cherubini says it's clear that societies need to embrace this kind of change, along with improving and intensifying agricultural production.

Especially in places like Africa, where there is a gap between what the land could potentially produce and what is produced, there's a great need for improvements, he said.

"We need to produce more with less so that land is available for other uses," he said. "What is clear, is that we need to change. We need cross-sectoral changes in our lifestyles and in our economies."

Although these changes will cost money, the IPCC report emphasizes that the costs of inaction will exceed the costs of immediate action in many areas. That means that money spent now can be seen as a sound investment, he said.

"These changes do not come for free, they do have a cost," he said. "But should we talk about costs, or should we rather call it an investment?"

Explore further

World warned: change now or endanger food and climate

More information: IPCC Report—Climate Change and Land: www.ipcc.ch/report/srccl/
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Aug 08, 2019
But, the meat eaters won't listen. What to do?

Aug 10, 2019
But, the meat eaters won't listen. What to do?

The problem with the vegetarian diet is that plants are very thin in proteins, and many of their proteins are of the wrong types or harmful (e.g. gluten, lectin). You have to gorge yourself with foodstuffs that are not readily available in many places to get enough of the right stuff.

If you don't have a concentrated source of proteins to substitute meat, a lot of people will get sick by having to survive on very unbalanced diets that consist mostly of starches and fat.

I tried to buy veggie burgers the other day, but they cost $9.80 for two simple patties - so I bought minced beef for $3.50 and made burgers for the whole family. The price reflects the production costs and resource use; simply because it's vegetarian doesn't mean it's efficient.

Aug 10, 2019
The issue with vegetarian meat substitutes is that the processes used for extracting and converting the proteins actually throw away most of the calorific content of the food, and consume a lot of energy while doing so.

You may grow so many tons of protein on a field of soy, but when you want to eat those proteins you have to convert the proteins to avoid getting a belly ache and anemia - so you make tofu which is basically bean cheese - and in the process you boil stuff and ferment stuff, and throw away a whole bunch of inedible starches and proteins and fats...

The trick is that the people who are doing the bean counting are only counting the beans and not the cheese. They assume the plants are directly edible as protein, so the calculations show that going vegetarian is highly efficient, but when you take in the requirement to convert the proteins it becomes just as efficient if not more so to feed the soybeans to chickens and cows.

Aug 10, 2019
For example:

feed conversion ratio (FCR) or feed conversion rate is a ratio or rate measuring of the efficiency with which the bodies of livestock convert animal feed into the desired output. For dairy cows, for example, the output is milk, whereas in animals raised for meat (such as beef cows,[1] pigs, chickens, and fish) the output is the flesh

For poultry the FCR is 1.6 and assuming the resulting meat is 60% protein, you get a feed-to-protein conversion ratio of around 4.2 meaning 4.2 units of feed produces 1 unit of protein.

Meanwhile, a soybean contains about 20% protein, so assuming no loss and all proteins to be convertible, you get a soy-to-protein conversion ratio of 5.

This means you get more proteins out of feeding the soybeans to chickens than eating the beans yourself. The ratio gets better for other sources such as corn, wheat, etc. which contain less proteins but are cheaper to farm.

Aug 10, 2019
Of course, eating the soybeans yourself gives you more calories than feeding them to the chicken, but the point isn't about getting more calories - it's about getting a healthy balanced diet.

If you're counting just the food calories, you get obesity issues as people automatically compensate for the lack of proteins (or specific nutrients in general) by eating more food to gain it.

Aug 10, 2019
The left need to control every aspect of your life. As they travel on their private jets and mega yachts they ponder which insects you should be eating and how much energy you are entitled to. In other words you have no real rights.

Aug 10, 2019

The point of animals as food is that they convert starches and fats into protein, whereas vegetarianism has only access to the proteins that are directly edible and available in the plants - which is not a lot. If you want to ditch meat, you should genetically engineer a plant that is somewhere around 50% edible proteins by mass.

Quorn comes close - fungi are high in proteins - but they're not the same composition of proteins as meat so it's still lower quality (you need to eat more of it to get enough).

Aug 10, 2019
As we speak trees are being cut down in NA and being shipped to the UK for their Drax bio-energy plant. Meanwhile they say that your evening hamburger is killing the planet.

Aug 10, 2019
As we speak trees are being cut down in NA and being shipped to the UK for their Drax bio-energy plant. Meanwhile they say that your evening hamburger is killing the planet.

The reason they're importing is because the powerplant burns so much wood chips that it's consuming the equivalent of 2/3 of the European production of energy biomass. They simply don't have enough supply locally.

Other than the amount of diesel required to ship the wood over, I don't see what the problem is. Trees grow back, and the Drax was one of the biggest coal-burning powerplants in the world before they switched it over to wood.

Aug 10, 2019
Yes Eikka trees do grow back but how many generations of trees can you harvest before the soils are depleted? Also, how much CO2 is not being absorbed by the trees that were harvested?

Aug 11, 2019
Yes Eikka trees do grow back but how many generations of trees can you harvest before the soils are depleted? Also, how much CO2 is not being absorbed by the trees that were harvested?

Quite many. Indefinite in theory, although like with any farming, you have to let the soil rest after so many crop cycles. The ash from biomass burning can be recycled back as fertilizer.

The point of CO2 is moot, since the trees come from commercial farmed forests anyhow. These are planted on forests that were previously clear-cut all the way back to the industrial revolution, so complaining about the CO2 is just crying over spilled milk.

Of course if you demand that so many more powerplants should be run like Drax, that could become an issue, but that's not really the case here. Good things in moderation remain good.

Aug 11, 2019
There were 2 links saying otherwise. Also, I really doubt that they ship the ashes back from the Drax plant and spread them over the ex-forrest.

Aug 11, 2019
And besides, the Drax powerplant is "flex-fuel", in that it burns just about anything that burns. They ran the biomass trials on locally produced shrubberies - it's just a question of ramping up production to the required 7.5 million tons per year.

Surely it would be cheaper to source the materials locally rather than ship it all across the Atlantic. Aside from wood, it also burns corn husks, peanut shells, straw, sunflower pellets, olives that have been squeezed for oil... etc. as it comes available.

If run solely on wood, it requires an area of 12,000 km2 which is a patch of forest about 110 km on the side.

Aug 11, 2019
There were 2 links saying otherwise. Also, I really doubt that they ship the ashes back from the Drax plant and spread them over the ex-forrest.

One of the links doesn't work, and the other just repeats the points made: critics complain that it takes decades for the wood to grow back - but it's still a closed cycle and that's the entire point of it.

Same point goes to the complaints about cutting down "hardwood forests". If they had been old-growth forests or clear-cutting instead of already farmed forests, the protesters would be jumping with joy and chaining themselves up all over the place - but it isn't, so they're reduced to making lame rhetorical jabs and "implications" to suggest there's something shady going on.

Regarding the ashes: the soil nutrient loss isn't presently an issue. If it becomes an issue, the solutions are ready and waiting.

Aug 11, 2019
There were 2 links saying otherwise.

Having found other references to the first link; they're talking about the "carbon debt" caused by cutting down naturally regenerating forests, and some other particular cases which would make the biomass burning worse than coal - but this is a false point because no new carbon is being added to the atmosphere and you're comparing a one-time emission to continuous emissions which is simply apples-to-oranges.

Biomass burning can be worse than coal - initially - and it continues to emit some net carbon due to the continued use of fossil fuels in the process chain, but in the end it saves more than 90% of the emissions in the long term.

The main question is rather about the carbon debt payback period - and whether that is short enough to matter for the climate agreements for keeping global warming under 1.5 C - which is an arbitrary goal that can't be met with biomass burning alone anyhow.

Aug 11, 2019
In the end, biomass remains one of the very few fuels that can provide reliable base- and load following generation on the electric and the heating grids because it can be stockpiled and dispatched.

Even if it was just as bad as coal on timescales relevant to the climate change targets, it is still essential for the rest of the system to operate without fossil fuels in the first place. If you don't have -something- you can throw in a boiler and burn for energy as the need comes, you're looking at energy rationing ("demand management") for entire nations, which makes it very difficult for market economies to function - they break down to planned economies and cronyism or state capitalism.

But that's the real Hintergedanke of the opposition: no solution that keeps "capitalism" running can be a good solution. Only those solutions that lead to reliance on state central control are acceptable, because they give power to the people who position themselves to run the system.

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