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Obvious & Low-cost Responses to the Perceived Climate Change Threat
As trees grow, they absorb and store carbon dioxide emissions while releasing oxygen. In fact, a new study published in the journal Science found that restoring the world’s forests on an unprecedented scale would be “the best climate change solution available.” The new research proposes a worldwide planting program that could remove two-thirds of all the emissions from human activities that remain in the atmosphere today, a figure the scientists describe as “mind-blowing”.
The analysis found that there are 1.7 billion hectares of treeless land on which 1.2 trillion native tree saplings would naturally grow. (There are 2.47 acres in one hectare) That area represents 11% of the world’s land area and is equivalent to the size of the United States and China combined. Under this plan, many tropical areas would have 100% tree cover, while other areas would be more sparsely covered. This means that, on average, about half the world’s land area would be under a tree canopy.
The scientists at the Swiss university, ETH Zurich, specifically excluded urban areas from their analysis as well as all fields used to grow crops. But they did include grazing land, on which the researchers say a few additional trees per hectare will also benefit sheep and cattle.
As Professor Tom Crowther who led the research argues, “This new quantitative evaluation shows [that forest] restoration isn’t just one of our climate change solutions, it is overwhelmingly the top one.” Crowther goes on to say, “What blows my mind is the scale. I thought restoration would be in the top 10, but it is overwhelmingly more powerful than any of the other climate change solutions proposed.”
Interestingly, planting billions of trees across the world is one of the biggest and cheapest ways of taking CO2out of the atmosphere and resolving the alleged climate crisis. Furthermore, these trees could be planted without encroaching on cropland or urban areas.
So, regardless of whether you think anthropogenic climate change is an existential threat to civilization or merely “a small price to pay for a more affluent world,” more trees represent the kind of affordable adaptation that makes sense. And while it’s a big challenge, the idea of reforesting much of the world isn’t as far-fetched as it might sound.
Consider the facts.
Since the dawn of agriculture, humans have cut down three trillion trees, which is about half the trees on Earth. In recognition of this fact, Tree planting initiatives already exist; for instance, the Bonn Challenge, backed by 48 nations, aims to restore 350 million hectares of forest by 2030. That’s an area twelve times the size of the United Kingdom.
Notably, “rewilding and reforesting habitats” is likely to become easier and less disruptive in the near future. This may seem like a strange prediction, given that the global population is expected to grow from 7.7 billion today to 10 billion by 2050. But, by then, nearly 70% of the world’s population will live in and around cities. The newly abandoned rural areas in many countries will become ripe for restoration. We are seeing this happen already. In Europe, 2.2 million hectares of forest per year regrew between 2000 and 2015, and forest cover in Spain has increased from 8% of the country’s territory in 1900 to 25% today.
In addition to these examples, massive reforestation has already delivered real benefits for people. In the late 1990s, environmental deterioration in China became critical, with vast areas resembling the Dust Bowl of the American Midwest in the 1930s. Six bold programs were introduced, targeting over 100 million hectares of land for reforestation.
The largest and best known of these initiatives was called Grain for Green. It reduced soil erosion and stabilized local rainfall patterns. The ongoing program has also helped alleviate poverty by making payments directly to farmers who set aside their land for reforestation.
Importantly, reforesting 900 million of the 1.7 billion hectares of treeless land could be done without adversely impacting our capacity to grow food. This finding is in line with other estimates. In fact, reforestation may even result in production from farmland increasing. Why? Because, as the Chinese projects demonstrated, the return of forests leads to more stable rainfall and more fertile soil, which leads to increased crop yields per acre.
How much will this cost? Crowther says, “The most effective projects are doing restoration for thirty U.S. cents per tree. That means we could restore 1 trillion trees for $300 billion, though obviously that means immense efficiency and effectiveness.”
Effective tree-planting could take place across the world. The potential is literally everywhere. In terms of carbon capture, you get by far your biggest bang for your buck in the tropics [where canopy cover is 100%] but every one of us can get involved. The world’s six biggest nations, Russia, Canada, China, the U.S., Brazil, and Australia, contain half the potential restoration sites.
The Swiss study showed that about two-thirds of all land, totaling 8.7 billion hectares, could support a forest, and that 5.5 billion hectares already has trees. Of the 3.2 billion hectares of treeless land, 1.5 billion hectares are used for growing food, leaving 1.7 billion hectares of potential forest land in areas that were previously degraded or sparsely vegetated.
Earlier research by Crowther’s team calculated that there are currently about 3 trillion trees in the world, which is about half the number that existed before the rise of human civilization. Meanwhile, the world still has a net loss of about 10 billion trees a year.
Some experts have expressed skepticism about how much CO₂ 900 million hectares of new forest could store.
The new research focuses on the 205 billion metric tons of carbon sequestered by the new forests. However, after netting out the carbon stored in the degraded vegetation, which is currently on this land, it appears that the new forests could store on average an extra 57 billion metric tons of carbon.
Some argue that some warming will continue in spite of the trees and that will suppress the growth rate of the trees. However, any adverse impact of higher temperatures on plant growth will be more than offset by the impact of carbon dioxide fertilization. That means, when there are higher levels of carbon dioxide in the atmosphere, photosynthesis is more efficient, meaning plants need less water and can still be productive at higher temperatures. And,
Best of all, since the best sequestration occurs in “new growth” forests with “mixed species,” the focus will be on planting, growing and harvesting trees to create high-strength, very long-lived building materials. Unlike paper and low-quality forest products, these “engineered materials” will be specifically designed to prevent decomposition, which would release carbon dioxide back into the atmosphere. Assuming that half of the new forest is harvested every 15 years on average from 2030 to 2100, the cumulative net impact should be at least 140 billion metric tons sequestered. And that’s not even counting the impact of reduced carbon emissions as the use of concrete is scaled back and the higher productivity of new tree species engineered for sequestration is factored in.
What’s the bottom line?
Planting 1 trillion trees at a cost of $300 billion would be one of the most cost-effective ways to dramatically reduce atmospheric CO2. If the investment is spaced over 15 years that’s only about $2.50 per person per year, globally. Even better, new “materials technology” will turn this $300 billion investment into a positive-ROI industry, while transforming the lives of people across Africa, South Asia, and Latin America.
Furthermore, this business case will only get better as we supplement naturally occurring species with GMOs designed for hot, arid, and even toxic conditions.
As such, reforestation represents precisely the type of high-ROI adaptation that people will be willing to make in order to eliminate the possibility of catastrophic climate change. In short, if any project ever warranted the enthusiastic support of USAID or the Gates Foundation, this is it.
Given this trend, we offer the following forecasts for your consideration.
First, don’t expect the so-called “allies” behind World War Zero to pay more than lip service to reforestation and similar “smart climate adaptations.”
Unlike invasive windmills and solar panels, trees and other natural solutions don’t make people more dependent on government or stifle personal autonomy. Trees also represent a solution that potentially raises indigenous peoples out of abject poverty. Therefore, the funders who invest in such a vision will be pragmatic realists, rather than self-absorbed idealists.
Second, in order to deliver the best results, many characteristics of the forests will be fine-tuned for local conditions.
A quick review of the literature indicates that many factors help determine the effectiveness of forests in sequestering CO2. For example, new growth forests are much more effective than old-growth forests. Similarly, a mixture of species, as found in natural forests, is more effective than large-scale monoculture forests. Furthermore, temperate climate forests appear to be more effective at long-term sequestration than tropical forests, because tropical forests lose stored CO2 at a higher rate. By combining these and other insights with the creation of new tree varieties optimized specifically for this purpose, science will be able to dramatically increase the ROI of reforestation relative to the base-case we’ve discussed.
Third, genetically modified trees will soon make the whole process dramatically more efficient.
On average naturally occurring trees only capture 2-to-3 percent of the carbon flowing through them; the rest is returned to the atmosphere. Doubling this carbon capture efficiency would eliminate arguments for reducing or ending the global consumption of fossil fuels. And fortunately, this research is already underway at places including the U.S. Department of Energy’s Joint Genome Institute. They’ve created a new carbon fixation pathway using ECRs; the supercharged enzymes are capable of fixing CO2 at a rate nearly 20 times faster than RuBisCo, the most prevalent CO2-fixing enzyme in nature. This should soon lead to the introduction of synthetic CO2-fixation cycles into trees and other organisms to bolster natural carbon capture.
Fourth by 2030, reforestation and engineered forest products will combine to create a new carbon-negative industry dramatically impacting global living standards.
Architects, engineers, material scientists, and chemists are paving the way for skyscrapers, houses and other structures made from strong, very long-lived wooden materials. Coupled with massive reforestation, this technology will pave the way for a whole new industry providing jobs, housing, and infrastructure for a billion or so people left behind by prior techno-economic revolutions. And,
Fifth, across the 21st Century timeframe, harnessing the power of whales, will complement reforestation as a cost-effective adaptation to the perceived threat of climate change.
Oceans help regulate the climate by holding 50 times more CO₂ than the atmosphere. So, even a small change in the way carbon enters the oceans could affect the CO₂ storage capacity. For example, if we helped whale populations rise from 1.3 million today to their pre-whaling numbers of 4-to-5 million, they could capture 1.7 billion metric tons of CO₂ annually (or 119 billion metric tons from 2030 to 2100) - with the cost of protecting them at just $13 per person a year. How? First, over a lifespan of around 60 years, whales accumulate an average of 33 metric tons of CO₂. When they die, they sink to the bottom of the ocean, locking that carbon away for hundreds of years. More importantly, whales increase phytoplankton productivity. As they rise-up through the ocean to breathe and migrate across the globe, the iron and nitrogen in their waste provide ideal growing conditions for these microscopic organisms. - Although commercial whaling has been officially banned since 1986, more than 1,000 whales a year are still killed for commercial purposes. Rigorous sanctions against whaling nations, coupled with other whale-friendly programs could dramatically reduce atmospheric greenhouse gases without impeding global economic growth.
References
1. 05 Jul 2019. Jean-Francois Bastin, Yelena Finegold, Claude Garcia, Danilo Mollicone, Marcelo Rezende, Devin Routh, Constantin M. Zohner, & Thomas W. Crowther. The global tree restoration potential.
https://science.sciencemag.org/content/365/6448/76
2. 2019. Simon L. Lewis, Charlotte E. Wheeler, Edward T. A. Mitchard & Alexander Koch. Regenerate natural forests to store carbon.
https://www.nature.com/articles/d41586-019-01026-8
3. com. May 7, 2019. Jeff McMahon. What If GMOs Can Fight Climate Change?
4. Genetic Engineering & Biotechnology News. November 21, 2016. GMOs and carbon fixation: Trapping CO2 in engineered plants and trees to convert it to energy.
5. World Economic Forum. July 2019. Simon Lewis & Mark Maslin. Massive reforestation is key to averting a climate catastrophe.
6. The Guardian. 18 Oct 2019. Damian Carrington. Tree planting has mind-blowing potential to tackle the climate crisis.
7. UK. 20 NOVEMBER 2019. Helena Horton. Saving the whale is more important than planting trees when it comes to climate change, scientists argue.
8. 2019. Pugh et al. The role of forest regrowth in global carbon sink dynamics.
https://www.pnas.org/content/116/10/4382
9. com. January 14, 2019. Jeff Spross. How to build a skyscraper out of wood.
https://theweek.com/articles/816653/how-build-skyscraper-wood
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