How to tackle the global deforestation crisis

Imagine if France, Germany, and Spain were completely blanketed in forests -- and then all those trees were quickly chopped down. That's nearly the amount of deforestation that occurred globally between 2001 and 2020, with profound consequences.

Deforestation is a major contributor to climate change, producing between 6 and 17 percent of global greenhouse gas emissions, according to a 2009 study. Meanwhile, because trees also absorb carbon dioxide, removing it from the atmosphere, they help keep the Earth cooler. And climate change aside, forests protect biodiversity.

"Climate change and biodiversity make this a global problem, not a local problem," says MIT economist Ben Olken. "Deciding to cut down trees or not has huge implications for the world."

But deforestation is often financially profitable, so it continues at a rapid rate. Researchers can now measure this trend closely: In the last quarter-century, satellite-based technology has led to a paradigm change in charting deforestation. New deforestation datasets, based on the Landsat satellites, for instance, track forest change since 2000 with resolution at 30 meters, while many other products now offer frequent imaging at close resolution.

"Part of this revolution in measurement is accuracy, and the other part is coverage," says Clare Balboni, an assistant professor of economics at the London School of Economics (LSE). "On-site observation is very expensive and logistically challenging, and you're talking about case studies. These satellite-based data sets just open up opportunities to see deforestation at scale, systematically, across the globe."

Balboni and Olken have now helped write a new paper providing a road map for thinking about this crisis. The open-access article, "The Economics of Tropical Deforestation," appears this month in the Annual Review of Economics. The co-authors are Balboni, a former MIT faculty member; Aaron Berman, a PhD candidate in MIT's Department of Economics; Robin Burgess, an LSE professor; and Olken, MIT's Jane Berkowitz Carlton and Dennis William Carlton Professor of Microeconomics. Balboni and Olken have also conducted primary research in this area, along with Burgess.

So, how can the world tackle deforestation? It starts with understanding the problem.

Replacing forests with farms

Several decades ago, some thinkers, including the famous MIT economist Paul Samuelson in the 1970s, built models to study forests as a renewable resource; Samuelson calculated the "maximum sustained yield" at which a forest could be cleared while being regrown. These frameworks were designed to think about tree farms or the U.S. national forest system, where a fraction of trees would be cut each year, and then new trees would be grown over time to take their place.

But deforestation today, particularly in tropical areas, often looks very different, and forest regeneration is not common.

Indeed, as Balboni and Olken emphasize, deforestation is now rampant partly because the profits from chopping down trees come not just from timber, but from replacing forests with agriculture. In Brazil, deforestation has increased along with agricultural prices; in Indonesia, clearing trees accelerated as the global price of palm oil went up, leading companies to replace forests with palm tree orchards.

All this tree-clearing creates a familiar situation: The globally shared costs of climate change from deforestation are "externalities," as economists say, imposed on everyone else by the people removing forest land. It is akin to a company that pollutes into a river, affecting the water quality of residents.

"Economics has changed the way it thinks about this over the last 50 years, and two things are central," Olken says. "The relevance of global externalities is very important, and the conceptualization of alternate land uses is very important." This also means traditional forest-management guidance about regrowth is not enough. With the economic dynamics in mind, which policies might work, and why?

The search for solutions

As Balboni and Olken note, economists often recommend "Pigouvian" taxes (named after the British economist Arthur Pigou) in these cases, levied against people imposing externalities on others. And yet, it can be hard to identify who is doing the deforesting.

Instead of taxing people for clearing forests, governments can pay people to keep forests intact. The UN uses Payments for Environmental Services (PES) as part of its REDD+ (Reducing Emissions from Deforestation and forest Degradation) program. However, it is similarly tough to identify the optimal landowners to subsidize, and these payments may not match the quick cash-in of deforestation. A 2017 study in Uganda showed PES reduced deforestation somewhat; a 2022 study in Indonesia found no reduction; another 2022 study, in Brazil, showed again that some forest protection resulted.

"There's mixed evidence from many of these [studies]," Balboni says. These policies, she notes, must reach people who would otherwise clear forests, and a key question is, "How can we assess their success compared to what would have happened anyway?"

Some places have tried cash transfer programs for larger populations. In Indonesia, a 2020 study found such subsidies reduced deforestation near villages by 30 percent. But in Mexico, a similar program meant more people could afford milk and meat, again creating demand for more agriculture and thus leading to more forest-clearing.

At this point, it might seem that laws simply banning deforestation in key areas would work best -- indeed, about 16 percent of the world's land overall is protected in some way. Yet the dynamics of protection are tricky. Even with protected areas in place, there is still "leakage" of deforestation into other regions.

Still more approaches exist, including "nonstate agreements," such as the Amazon Soy Moratorium in Brazil, in which grain traders pledged not to buy soy from deforested lands, and reduced deforestation without "leakage."

Also, intriguingly, a 2008 policy change in the Brazilian Amazon made agricultural credit harder to obtain by requiring recipients to comply with environmental and land registration rules. The result? Deforestation dropped by up to 60 percent over nearly a decade.

Politics and pulp

Overall, Balboni and Olken observe, beyond "externalities," two major challenges exist. One, it is often unclear who holds property rights in forests. In these circumstances, deforestation seems to increase. Two, deforestation is subject to political battles.

For instance, as economist Bard Harstad of Stanford University has observed, environmental lobbying is asymmetric. Balboni and Olken write: "The conservationist lobby must pay the government in perpetuity … while the deforestation-oriented lobby need pay only once to deforest in the present." And political instability leads to more deforestation because "the current administration places lower value on future conservation payments."

Even so, national political measures can work. In the Amazon from 2001 to 2005, Brazilian deforestation rates were three to four times higher than on similar land across the border, but that imbalance vanished once the country passed conservation measures in 2006. However, deforestation ramped up again after a 2014 change in government. Looking at particular monitoring approaches, a study of Brazil's satellite-based Real-Time System for Detection of Deforestation (DETER), launched in 2004, suggests that a 50 percent annual increase in its use in municipalities created a 25 percent reduction in deforestation from 2006 to 2016.

How precisely politics matters may depend on the context. In a 2021 paper, Balboni and Olken (with three colleagues) found that deforestation actually decreased around elections in Indonesia. Conversely, in Brazil, one study found that deforestation rates were 8 to 10 percent higher where mayors were running for re-election between 2002 and 2012, suggesting incumbents had deforestation industry support.

"The research there is aiming to understand what the political economy drivers are," Olken says, "with the idea that if you understand those things, reform in those countries is more likely."

Looking ahead, Balboni and Olken also suggest that new research estimating the value of intact forest land intact could influence public debates. And while many scholars have studied deforestation in Brazil and Indonesia, fewer have examined the Democratic Republic of Congo, another deforestation leader, and sub-Saharan Africa.

Deforestation is an ongoing crisis. But thanks to satellites and many recent studies, experts know vastly more about the problem than they did a decade or two ago, and with an economics toolkit, can evaluate the incentives and dynamics at play.

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1. 5-degree goal not plausible: Social change more important than physical tipping points

Limiting global warming to 1.5 degrees Celsius is currently not plausible, as is shown in a new study released by Universität Hamburg's Cluster of Excellence "Climate, Climatic Change, and Society" (CLICCS). Climate policy, protests, and the Ukraine crisis: the participating researchers systematically assessed to what extent social changes are already underway -- while also analyzing certain physical processes frequently discussed as tipping points. Their conclusion: social change is essential to meeting the temperature goals set in Paris. But what has been achieved to date is insufficient. Accordingly, climate adaptation will also have to be approached from a new angle.

The interdisciplinary team of researchers addressed ten important drivers of social change: "Actually, when it comes to climate protection, some things have now been set in motion. But if you look at the development of social processes in detail, keeping global warming under 1.5 degrees still isn't plausible," says CLICCS Speaker Prof. Anita Engels. According to the Hamburg Climate Futures Outlook, especially consumption patterns and corporate responses are slowing urgently needed climate protection measures. Other key factors like UN climate policy, legislation, climate protests and divestment from the fossil fuels are supporting efforts to meet the climate goals. As the analysis shows, however, this positive dynamic alone won't suffice to stay within the 1.5-degree limit. "The deep decarbonization required is simply progressing too slowly," says Engels.

In addition, the team assesses certain physical processes that are frequently discussed as tipping points: the loss of the Arctic sea ice and melting ice sheets are serious developments -- as are regional climate changes. But they will have very little influence on the global temperature until 2050. In this regard, a thawing permafrost, weakened Atlantic Meridional Overturning Circulation (AMOC), and the loss of the Amazon Forest are more important factors -- albeit only moderately. "The Fact is: these feared tipping points could drastically change the conditions for life on Earth -- but they're largely irrelevant for reaching the Paris Agreement temperature goals," explains CLICCS Co-Speaker Prof. Jochem Marotzke from the Max Planck Institute for Meteorology.

The study also covers COVID-19 and the Russian invasion of Ukraine: economic reconstruction programs have reinforced dependence on fossil fuels, which means the necessary changes are now less plausible than previously assumed. In contrast, whether efforts to safeguard Europe's power supply and the international community's attempts to become independent of Russian gas will undermine or accelerate the phasing out of fossil fuels in the long run remains unclear.

Importance of human agency, new approach to adaptation

The Outlook is currently the only assessment that interlinks social sciences and natural sciences analysis in an integrated study to assess the plausibility of certain climate futures. More than 60 experts have contributed. According to the study, the best hope for shaping a positive climate future lies in the ability of society to make fundamental changes ("human agency"). In addition, the Outlook reveals a range of conditions for doing so, for instance that transnational initiatives and non-government actors continue to support climate protection, and that protests keep up the pressure on politicians.

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In spreading politics, videos may not be much more persuasive than their text-based counterparts

It might seem that video would be a singularly influential medium for spreading information online. But a new experiment conducted by MIT researchers finds that video clips have only a modestly larger impact on political persuasion than the written word does.

"Our conclusion is that watching video is not much more persuasive than reading text," says David Rand, an MIT professor and co-author of a new paper detailing the study's results.

The study comes amid widespread concern about online political misinformation, including the possibility that technology-enabled "deepfake" videos could easily convince many people watching them to believe false claims.

"Technological advances have created new opportunities for people to falsify video footage, but we still know surprisingly little about how individuals process political video versus text," says MIT researcher Chloe Wittenberg, the lead author on the paper. "Before we can identify strategies for combating the spread of deepfakes, we first need to answer these more basic questions about the role of video in political persuasion."

The paper, "The (Minimal) Persuasive Advantage of Political Video over Text," is published today in Proceedings of the National Academy of Sciences. The co-authors are Adam J. Berinsky, the Mitsui Professor of Political Science; Rand, the Erwin H. Schell Professor and Professor of Management Science and Brain and Cognitive Sciences; Ben Tappin, a postdoc in the Human Cooperation Lab; and Chloe Wittenberg, a doctoral student in the Department of Political Science.

Believability and persuasion

The study operates on a distinction between the credibility of videos and their persuasiveness. That is, an audience might find a video believable, but their attitudes might not change in response. Alternately, a video might not seem credible to a large portion of the audience but still alter viewers' attitudes or behavior.

For example, Rand says, "When you watch a stain remover ad, they all have this same format, where some stain gets on a shirt, you pour the remover on it, and it goes in the washer and hey, look, the stain is gone. So, one question is: Do you believe that happened, or was it just trickery? And the second question is: How much do you want to buy the stain remover? The answers to those questions don't have to be tightly related."

To conduct the study, the MIT researchers performed a pair of survey experiments involving 7,609 Americans, using the Lucid and Dynata platforms. The first study involved 48 ads obtained through the Peoria Project, an archive of political materials. Survey participants either watched an ad, read a transcript of the ad, or received no information at all. (Each participant did this multiple times.) For each ad, participants were asked whether the message seemed believable and whether they agreed with its main message. They were then shown a series of questions measuring whether they found the subject personally important and whether they wanted more information.

The second study followed the same format but involved 24 popular video clips about Covid-19, taken from YouTube.

Overall, the results showed that video performed somewhat better than written text on the believability front but had a smaller relative advantage when it came to persuasion. Participants were modestly more likely to believe that events actually occurred when they were shown in a video as opposed to being described in a written transcript. However, the advantage of video over text was only one-third as big when it came to changing participants' attitudes and behavior.

As a further indication of this limited persuasive advantage of video versus text, the difference between the "control condition" (with participants who received no information) and reading text was as great as that between reading the transcript and watching the video.

These differences were surprisingly stable across groups. For instance, in the second study, there were only small differences in the effects seen for political versus nonpolitical messages about Covid-19, suggesting the findings hold across varying types of content. The researchers also did not find significant differences among the respondents based on factors such as age, political partisanship, and political knowledge.

"Seeing may be believing," Berinsky says, "but our study shows that just because video is more believable doesn't mean that it can change people's minds."

Questions about online behavior

The scholars acknowledge that the study did not exactly replicate the conditions in which people consume information online, but they suggest that the main findings yield valuable insight about the relative power of video versus text.

"It's possible that in real life things are a bit different," Rand says. "It's possible that as you're scrolling through your newsfeed, video captures your attention more than text would. You might be more likely to look at it. This doesn't mean that video is inherently more persuasive than text -- just that it has the potential to reach a wider audience."

That said, the MIT team notes there are some clear directions for future research in this field -- including the question of whether or not people are more willing to watch videos than to read materials.

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In politics and pandemics, trolls use fear, anger to drive clicks

Facebook users flipping through their feeds in the fall of 2016 faced a minefield of targeted advertisements pitting blacks against police, southern whites against immigrants, gun owners against Obama supporters and the LGBTQ community against the conservative right.

Placed by distant Russian trolls, they didn't aim to prop up one candidate or cause, but to turn Americans against one another.

The ads were cheaply made and full of threatening, vulgar language.

And, according to a sweeping new analysis of more than 2,500 of the ads, they were remarkably effective, eliciting clickthrough rates as much as nine times higher than what is typical in digital advertising.

"We found that fear and anger appeals work really well in getting people to engage," said lead author Chris Vargo, an assistant professor of Advertising, Public Relations and Media Design at University of Colorado Boulder.

The study, published this week in Journalism and Mass Communication Quarterly, is the first to take a comprehensive look at ads placed by the infamous Russian propaganda machine known as the Internet Research Agency (IRA) and ask: How effective were they? And what makes people click on them?

While focused on ads running in 2016, the study's findings resonate in the age of COVID-19 and the run-up to the 2020 election, the authors say.

"As consumers continue to see ads that contain false claims and are intentionally designed to use their emotions to manipulate them, it's important for them to have cool heads and understand the motives behind them," said Vargo.

For the study, Vargo and assistant professor of advertising Toby Hopp scoured 2,517 Facebook and Instagram ads downloaded from the U.S. House of Representatives Permanent Select Committee On Intelligence website. The committee made the ads publicly available in 2018 after concluding that the IRA had been creating fake U.S. personas, setting up fake social media pages, and using targeted paid advertising to "sow discord" among U.S. residents.

Using computational tools and manual coding, Vargo and Hopp analyzed every ad, looking for the inflammatory, obscene or threatening words and language hostile to a particular group's ethnic, religious or sexual identity. They also looked at which groups each ad targeted, how many clicks the ad got, and how much the IRA paid.

Collectively, the IRA spent about $75,000 to generate about 40.5 million impressions with about 3.7 million users clicking on them -- a clickthrough rate of 9.2%.

That compares to between .9% and 1.8% for a typical digital ad.

While ads using blatantly racist language didn't do well, those using cuss words and inflammatory words (like "sissy," "idiot," "psychopath" and "terrorist") or posing a potential threat did. Ads that evoked fear and anger did the best.

One IRA advertisement targeting users with an interest in the Black Lives Matter movement stated: "They killed an unarmed guy again! We MUST make the cops stop thinking that they are above the law!" Another shouted: "White supremacists are planning to raise the racist flag again!" Meanwhile, ads targeting people who sympathized with white conservative groups read "Take care of our vets; not illegals" or joked "If you voted for Obama: We don't want your business because you are too stupid to own a firearm."

Only 110 out of 2,000 mentioned Donald Trump.

"This wasn't about electing one candidate or another," said Vargo. "It was essentially a make-Americans-hate-each-other campaign."

The ads were often unsophisticated, with spelling or grammatical errors and poorly photoshopped images. Yet at only a few cents to distribute, the IRA got an impressive rate of return.

"I was shocked at how effective these appeals were," said Vargo.

The authors warn that they have no doubt such troll farms are still at it.

According to some news reports, Russian trolls are already engaged in disinformation campaigns around COVID-19.

"I think with any major story, you are going to see this kind of disinformation circulated," said Hopp. "There are bad actors out there who have goals that are counter to the aspirational goals of American democracy, and there are plenty of opportunities for them to take advantage of the current structure of social media."

Ultimately, the authors believe better monitoring, via both machine algorithms and human reviewers, could help stem the tide of disinformation.

Read more at Science Daily