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Top 6 ways to suck greenhouse gases out of the atmosphere
Researchers evaluated the best and worst ways to remove greenhouse gases from the atmosphere in a recent report.
- A recent report from International Institute for Applied Systems Science evaluated six land-based methods for removing greenhouse gases from the atmosphere.
- Though they concluded that every technique would be a net positive for the world, some were riskier or costlier than others.
- Among the safest, cheapest, and overall best approaches were restoring the wetlands and soil carbon sequestration.
In 2016, the Paris Climate Agreement set out the ambitious goal of limiting the rise in global temperature to below 2°C above its preindustrial levels, preferably to 1.5°C. These numbers might seem small, but the amount of energy needed to transform the entire world's average temperature is tremendous, and so too are its effects. If, for instance, the global temperature blasts past that 2°C mark and reaches 4°C, then nearly all of the U.S. will turn into an uninhabitable desert.
But focusing too much on the doom-and-gloom that climate change discussions so often revolve around can be pretty exhausting. So, let's focus instead on possible solutions. If we're to stay below 2°C, we'll need to deploy a multifaceted strategy. Part of that has to be finding ways to remove the greenhouse gases already in our atmosphere.
Recently, researchers at the International Institute for Applied Systems Science looked at the top six land-based methods for sucking greenhouse gases out of the atmosphere to evaluate their costs, their benefits, and which might be our best options going forward. While some of them are more risky or higher cost than others, all of them were found to contribute in some way and to effectively remove greenhouse gases from out of atmosphere.
1. Afforestation and reforestation
Between 1990 and 2015, the world lost 290 million hectares of forest. Restoring these depleted reserves (reforestation) and planting in previously un-forested areas (afforestation) is a fairly simple, common-sense approach to fighting climate change. Trees suck CO2 out of the air and store it in their timber — not only that, but they also contribute to food production, help to regulate freshwater, offer habitats to animals, and provide jobs and recreation among other benefits.
On the other hand, afforestation and reforestation require a lot of water usage and take up land that could otherwise be used for farming. Despite this, the researchers estimated that this strategy could remove between 0.5 to 7 gigatons (that's a billion tons) of CO2 from the atmosphere. To put that into context, one estimate provided by Carbon Brief suggests that human beings have released 1,374 gigatons of CO2 into the atmosphere since the Industrial Revolution. We don't have to get rid of all of this extra CO2, fortunately; just enough to keep warming within acceptable bounds.
2. Wetland restoration
Wetlands might seem like an odd candidate for being one of the most beneficial features of the planet, but they have the potential to scrub another 2.7 gigatons of CO2 from the air. In fact, although wetlands cover 9 percent of the planet, they're estimated to deliver 23 percent of the total value offered by the globe's ecosystems.
For instance, wetlands are the best regulators of water resources out there—they're even sometimes intentionally developed near sewage plants to help filter out pollutants. They also provide habitats for keystone species, can help to produce certain crops (e.g., rice or cranberries), and are extremely resilient to rising sea levels.
Although they tend to release some methane, the amount of CO2 they suck up is well worth it. Regrettably, however, half of the globe's wetlands have been lost, making their restoration a top priority. In addition to being a cheap venture, the researchers also identified virtually no downsides to restoring wetlands.
3. Soil carbon sequestration
Like wetland restoration, soil carbon sequestration — storing carbon in the soil over the long term — presents few downsides. This can take place through a variety of mechanisms, the biggest one being the photosynthesis of plants. But smart crop management, like rotating crops, planting perennial crops (those that don't need to be replanted every year), and so on, can increase how much carbon is stored in the soil. So too can optimizing fertilizer usage, tilling less intensely, improving water management, and many other techniques. Implementing these techniques could result in a reduction of between 2 and 5 gigatons of CO2.
By farming with the conscious goal of sequestering more carbon in the soil, we also gain the benefit of having more useful soil for use in building materials, pharmaceuticals, electronics, and other industrial applications. Plus, it helps to prevent erosion, preserves the landscape, and increases crop yields.
Flickr user Oregon Department of Forestry
Biochar is the result of biomass pyrolysis; simply put, it's charcoal. When biomass is burned in a low- or no-oxygen environment, it becomes carbonized, locking that carbon into the material and preventing its transference to the atmosphere. Biochar stores carbon in a long-term, durable fashion. Typically, biochar is distributed in soil, where it can help improve food production and balance the pH of acidic soil. Microorganisms in soils also emit nitrous oxide, another greenhouse gas, but adding small amounts of biochar significantly reduces these emissions, along with other greenhouse gases other than CO2. Plus, producing biochar can also generate electricity.
However, biochar production has to be done carefully. If produced without following clean guidelines, biochar can actually release more greenhouse gases into the atmosphere. But if done correctly, producing biochar could reduce greenhouse gases by up to 2 gigatons of CO2 a year.
5. Terrestrial enhanced weathering
A considerable amount of chemistry is slowly but consistently being conducted beneath our feet. In particular, weathering plays an important role in soil chemistry. As the soil's minerals break down over time, they release nutrients and form secondary minerals, like clay. We can improve this process and encourage desirable soil chemistry by adding crushed silicate rocks rich in calcium and magnesium and low in metal ions like nickel or chromium. Basalt, for instance, would be a good candidate.
Doing so could reduce soil acidity and encourage the transformation of CO2 into bicarbonate ions, or HCO3-. As an added benefit, run-off HCO3- could increase ocean alkalinity, making the ocean more resistant to pH changes. Although it would have some positive effect, the researchers noted that field-scale assessments of this technique's interactions with other approaches — like reforestation — would be necessary to determine exactly how much terrestrial enhanced weathering could contribute to reducing greenhouse gas emissions.
6. Bioenergy carbon capture and storage (BECCS)
An engineer walks through the Bailey Bioenergy Facility in Washington, D.C.
Katherine Frey/The Washington Post via Getty Images
The use of BECCS is something of a one-two punch; it provides energy, avoiding the need to use fossil fuels, and as feedstocks grow for later use as fuel, they suck CO2 out of the atmosphere. Plants like switchgrass or giant reedgrass make for excellent BECCS feedstocks.
Generally, regular bioenergy is a carbon-zero product, since the fuel sequesters CO2 as it grows and releases CO2 as it's burned for energy. But incorporating carbon capture and storage (CCS) technology in this process results in negative emissions. This beats adding CCS technology to fossil fuel processes, since burning fossil fuels starts off by adding emissions to the atmosphere — existing CCS tech can therefore only reduce fossil fuel emissions, rather than turning them negative as is the case with bioenergy.
If BECCS were implemented at a large scale by the year 2100, it could remove 15 gigatons of CO2 per year. However, doing so would be expensive, and the land taken up to grow bioenergy feedstocks could be used instead to grow food. It would also require a greater use of fertilizers and would require a good amount of water to grow.
With the exception of wetland restoration and soil carbon sequestration, all of these approaches for greenhouse gas removal present some kind of downside that we would need to mitigate. The most challenging approaches would be afforestation/reforestation, BECCS, and biochar production, primarily due to their use of land that could otherwise grow food and their water requirements.
However, the researchers found that all of these methods for greenhouse gas removal would not only reduce greenhouse gases in the atmosphere, but, on balance, they would also make our lives better, either by creating jobs, reducing pollution, contributing food, promoting ecological diversity, or other ancillary benefits. Combating climate change is often presented as a costly venture, but in reality, it's more of an investment. By assessing the costs and benefits of approaches such as these six, we can get a better picture of what our return will be.
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A cave in France contains man’s earliest-known structures that had to be built by Neanderthals who were believed to be incapable of such things.
In a French cave deep underground, scientists have discovered what appear to be 176,000-year-old man-made structures. That's 150,000 years earlier than any that have been discovered anywhere before. And they could only have been built by Neanderthals, people who were never before considered capable of such a thing.
This is going to force a major shift in the way we see these early hominids. Researchers had thought that Neanderthals were profoundly primitive, and just barely human. This cave in France's Aveyron Valley changes all that: It's suddenly obvious that Neanderthals were not quite so unlike us.
According to The Atlantic, Bruniquel Cave was first explored in 1990 by Bruno Kowalsczewski, who was 15 at the time. He'd spent three years digging away at rubble covering a space through which his father felt air moving.
Some members of a local caving club managed to squeeze through the narrow, 30-meter long tunnel Kowalsczewski had dug to arrive in a passageway. They followed it past pools of water and old animal bones for over 330 meters before coming into a large chamber and a scene they had no reason to expect: Stalagmites that someone had broken into hundreds of small pieces, most of which were arranged into two rings—one roughly 6 meters across, and one 2 meters wide—with the remaining pieces stacked into one of four piles or leaning against the rings. There were also indications of fires and burnt bones.
Image source: Etienne FABRE - SSAC
A professional archeologist, Francois Rouzaud, determined with carbon dating that a burnt bear bone found in the chamber was 47,600 years old, which made the stalagmite structures older than any known cave painting. It also put the cave squarely within the age of the Neanderthals since they were the only humans in France that early. No one had suspected them of being capable of constructing complex forms or doing anything that far underground.
After Rouzard suddenly died in 1999, exploration at the cave stopped until life-long caver Sophie Verheyden, vacationing in the area, heard about it and decided to try and uranium-date the stalagmites inside.
The team she assembled eventually determined that the stalagmites had been broken up by people 176,000 years ago, way farther back even than Rouzard had supposed.
There weren't any signs that Neanderthals lived in the cave, so it's a mystery what they were up to down there. Verheyden thinks it's unlikely that a solitary artist created the tableaux, and so an organized group of skilled workers must've been involved. And “When you see such a structure so far into the cave, you think of something cultural or religious, but that's not proven," Verheyden told The Atlantic.
Whatever they built, the Bruniquel Cave reveals some big surprises about Neanderthals: They had fire, they built things, and likely used tools. Add this to recent discoveries that suggest they buried their dead, made art, and maybe even had language, and these mysterious proto-humans start looking a lot more familiar. A lot more like homo sapiens, and a lot more like distant cousins lost to history.
A recent study used fMRI to compare the brains of psychopathic criminals with a group of 100 well-functioning individuals, finding striking similarities.
- The study used psychological inventories to assess a group of violent criminals and healthy volunteers for psychopathy, and then examined how their brains responded to watching violent movie scenes.
- The fMRI results showed that the brains of healthy subjects who scored high in psychopathic traits reacted similarly as the psychopathic criminal group. Both of these groups also showed atrophy in brain regions involved in regulating emotion.
- The study adds complexity to common conceptions of what differentiates a psychopath from a "healthy" individual.
When considering what precisely makes someone a psychopath, the lines can be blurry.
Psychological research has shown that many people in society have some degree of malevolent personality traits, such as those described by the "dark triad": narcissism (entitled self-importance), Machiavellianism (strategic exploitation and deceit), and psychopathy (callousness and cynicism). But while people who score high in these traits are more likely to end up in prison, most of them are well functioning and don't engage in extreme antisocial behaviors.
Now, a new study published in Cerebral Cortex found that the brains of psychopathic criminals are structurally and functionally similar to many well-functioning, non-criminal individuals with psychopathic traits. The results suggest that psychopathy isn't a binary classification, but rather a "constellation" of personality traits that "vary in the non-incarcerated population with normal range of social functioning."
Assessing your inner psychopath
The researchers used functional magnetic resonance imaging (fMRI) to compare the brains of violent psychopathic criminals to those of healthy volunteers. All participants were assessed for psychopathy through commonly used inventories: the Hare Psychopathy Checklist-Revised and the Levenson Self-Report Psychopathy Scale.
Experimental design and sample stimuli. The subjects viewed a compilation of 137 movie clips with variable violent and nonviolent content.Nummenmaa et al.
Both groups watched a 26-minute-long medley of movie scenes that were selected to portray a "large variability of social and emotional content." Some scenes depicted intense violence. As participants watched the medley, fMRI recorded how various regions of their brains responded to the content.
The goal was to see whether the brains of psychopathic criminals looked and reacted similarly to the brains of healthy subjects who scored high in psychopathic traits. The results showed similar reactions: When both groups viewed violent scenes, the fMRI revealed strong reactions in the orbitofrontal cortex and anterior insula, brain regions associated with regulating emotion.
These similarities manifested as a positive association: The more psychopathic traits a healthy subject displayed, the more their brains responded like the criminal group. What's more, the fMRI revealed a similar association between psychopathic traits and brain structure, with those scoring high in psychopathy showing lower gray matter density in the orbitofrontal cortex and anterior insula.
There were some key differences between the groups, however. The researchers noted that the structural abnormalities in the healthy sample were mainly associated with primary psychopathic traits, which are: inclination to lie, lack of remorse, and callousness. Meanwhile, the functional responses of the healthy subjects were associated with secondary psychopathic traits: impulsivity, short temper, and low tolerance for frustration.
Overall, the study further illuminates some of the biological drivers of psychopathy, and it adds nuance to common conceptions of the differences between psychopathy and being "healthy."
Why do some psychopaths become criminals?
The million-dollar question remains unanswered: Why do some psychopaths end up in prison, while others (or, people who score high in psychopathic traits) lead well-functioning lives? The researchers couldn't give a definitive answer, but they did note that psychopathic criminals had lower connectivity within "key nodes of the social and emotional brain networks, including amygdala, insula, thalamus, and frontal pole."
"Thus, even though there are parallels in the regional responsiveness of the brain's affective circuit in the convicted psychopaths and well-functioning subjects with psychopathic traits, it is likely that the disrupted functional connectivity of this network is specific to criminal psychopathy."
Counterintuitively, directly combating misinformation online can spread it further. A different approach is needed.
- Like the coronavirus, engaging with misinformation can inadvertently cause it to spread.
- Social media has a business model based on getting users to spend increasing amounts of time on their platforms, which is why they are hesitant to remove engaging content.
- The best way to fight online misinformation is to drown it out with the truth.
A year ago, the Center for Countering Digital Hate warned of the parallel pandemics — the biological contagion of COVID-19 and the social contagion of misinformation, aiding the spread of the disease. Since the outbreak of COVID-19, anti-vaccine accounts have gained 10 million new social media followers, while we have witnessed arson attacks against 5G masts, hospital staff abused for treating COVID patients, and conspiracists addressing crowds of thousands.
Many have refused to follow guidance issued to control the spread of the virus, motivated by beliefs in falsehoods about its origins and effects. The reluctance we see in some to get the COVID vaccine is greater amongst those who rely on social media rather than traditional media for their information. In a pandemic, lies cost lives, and it has felt like a new conspiracy theory has sprung up online every day.
How we, as social media users, behave in response to misinformation can either enable or prevent it from being seen and believed by more people.
The rules are different online
Credit: Pool via Getty Images
If a colleague mentions in the office that Bill Gates planned the pandemic, or a friend at dinner tells the table that the COVID vaccine could make them infertile, the right thing to do is often to challenge their claims. We don't want anyone to be left believing these falsehoods.
But digital is different. The rules of physics online are not the same as they are in the offline world. We need new solutions for the problems we face online.
Now, imagine that in order to reply to your friend, you must first hand him a megaphone so that everyone within a five-block radius can hear what he has to say. It would do more damage than good, but this is essentially what we do when we engage with misinformation online.
Think about misinformation as being like the coronavirus — when we engage with it, we help to spread it to everyone else with whom we come into contact. If a public figure with a large following responds to a post containing misinformation, they ensure the post is seen by hundreds of thousands or even millions of people with one click. Social media algorithms also push content into more users' newsfeeds if it appears to be engaging, so lots of interactions from users with relatively small followings can still have unintended negative consequences.
The trend of people celebrating and posting photos of themselves or loved ones receiving the vaccine has been far more effective than any attempt to disprove a baseless claim about Bill Gates or 5G mobile technology.
Additionally, whereas we know our friend from the office or dinner, most of the misinformation we see online will come from strangers. They often will be from one of two groups — true believers, whose minds are made up, and professional propagandists, who profit from building large audiences online and selling them products (including false cures). Both of these groups use trolling tactics, that is, seeking to trigger people to respond in anger, thus helping them reach new audiences and thereby gaming the algorithm.
On the day the COVID vaccine was approved in the UK, anti-vaccine activists were able to provoke pro-vaccine voices into posting about thalidomide, exposing new audiences to a reason to distrust the medical establishment. Those who spread misinformation understand the rules of the game online; it's time those of us on the side of enlightenment values of truth and science did too.
How to fight online misinformation
Of course, it is much easier for social media companies to take on this issue than for us citizens. Research from the Center for Countering Digital Hate and Anti-Vax Watch last month found that 65% of anti-vaccine content on social media is linked to just twelve individuals and their organizations. Were the platforms to simply remove the accounts of these superspreaders, it would do a huge amount to reduce harmful misinformation.
The problem is that social media platforms are resistant to do so. These businesses have been built by constantly increasing the amount of time users spend on their platforms. Getting rid of the creators of engaging content that has millions of people hooked is antithetical to the business model. It will require intervention from governments to force tech companies to finally protect their users and society as a whole.
So, what can the rest of us do, while we await state regulation?
Instead of engaging, we should be outweighing the bad with the good. Every time you see a piece of harmful misinformation, share advice or information from a trusted source, like the WHO or BBC, on the same subject. The trend of people celebrating and posting photos of themselves or loved ones receiving the vaccine has been far more effective than any attempt to disprove a baseless claim about Bill Gates or 5G mobile technology. In the attention economy that governs tech platforms, drowning out is a better strategy than rebuttal.
Imran Ahmed is CEO of the Center for Countering Digital Hate.