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What Do the Numbers Show about Global Deforestation?

Blog Post | Forests

What Do the Numbers Show about Global Deforestation?

The Environmental Kuznets Curve is real.

Trees are icons of nature and significant carbon sinks, so anyone interested in climate change is invested in the fate of forests.

In recent weeks, Hannah Ritchie of Our World in Data has written several articles on deforestation. She had occasion to write on the subject because the quinquennial United Nations report Global Forest Resource Assessment (GFRA) was just released. It was filled with data and nuanced analysis on the State of the World’s Forests (another UN forestry report).

In one of Ritchie’s articles, she shows that the rate of deforestation peaked in the 1980s. Since then, the rate at which humans burn, chop, cut, and replace forests with farms and cities has fallen. And it’s not just modern industrial humans who used the natural world to excess – half of all forest loss took place before the year 1900. That point also illustrates how stunningly fast we shed trees in the 20th century. Roughly speaking, what took us ten thousand years to do before 1900, we managed to repeat in a mere hundred years. Deforestation, she notes, “is not a new problem.”

But it’s also not as bad as we think. The very same chart that illustrates the stunning extent of forest loss during settled human civilization also indicates that, relatively speaking, we have barely lost any forest coverage in the last twenty years.

Between 1990 and today, the Earth lost 177.5 million hectares of forests, an area about the size of Alaska. That’s a big area, but considering how large the Earth is and how mindbogglingly vast some of its forests are, it’s not that much (the GFRA estimates that the Earth’s total area classified as forests amounts to 4,060 million hectares or a bit below one-third of all habitable land).

More importantly, the rate of forest loss is tumbling: the decline in the 2010s was 40 percent below that of the 1990s. Plenty of us who are optimistic about nature and the state of human flourishing have predicted that the global deforestation rate will soon hit zero. In this GFRA report, we were almost right.

In the past decade, the yearly reduction in forest area was 0.12 percent – down from 0.19 percent in the 1990s and 0.35 percent in the 1980s. In other words, out of 100 hectares of forested area in 2010, 98.85 hectares still green the world today. Emphatically, we are not running out of forests.

What’s a bit worrying is that the deforestation rate itself has recently been dropping more slowly. Fortunately, the authors of the GFRA write that this slowdown is “due to a reduction in the rate of forest expansion,” not because humanity is ravenously clear-cutting the world’s forests. Indeed, we seem to have cut down fewer trees than in previous decades but have failed to replant (or let regrow) as many as we had before.

The silver lining to that observation is that regrowth and replanting is something that policymakers in the West and those of us who treasure the world’s forests can actually control, whereas persuading political leaders or poverty-stricken families of the Global South not to use the natural resources around them is a much more challenging and ethically dubious task.

Furthermore, while forest areas have declined, the remaining areas’ biomass has not. On the contrary, the biomass per unit of area increased by about 4 percent from 1990 to 2020, almost entirely offsetting the reduction in forest area (-4.2 percent) over that same period. Put differently, while the global forested area is smaller, forests have become greener and denser, nearly balancing out the total amount of biomass. This vegetation boom happened because, as the concentration of CO2 in the atmosphere increases, the growth of everything green accelerates – which makes sense since CO2 is plant food.

The stock of sequestered carbon in roots, soil, branches, and trunks is today level with what it was in 2010, and only 1 percent less than what it was in 1990 – an annual rate of decline of 0.03 percent. While the world’s forests are not without their (largely local) problems, the amount of green in the world is tantalizingly close to stabilization. All of us, from climate alarmists to optimists, should cherish that.

Even more extraordinary is the decline of deforestation across South America. In the 2010s, the deforested area was half that of the previous decade (2.6 million hectares vs. 5.2 million hectares in the 2000s). Despite all the doom and gloom about Brazil’s relatively modest increase in deforestation under President Jair Bolsonaro, the more than 700 contributors to the GFRA report conclude that “the deforestation hotspot is now in Africa.”

While Brazil was the single-largest deforester in the 2010s (15 million hectares), its reduction in total forest area is not far above the Democratic Republic of Congo (11 million hectares). Combining the DRC’s deforestation with that of Angola (6 million hectares) and Tanzania (4 million hectares) shows that Africa’s deforestation is more worrying than Brazil’s Amazonian blunders.

I and many others investigating the Environmental Kuznets Curve (an inverted-U shape relationship between income per capita and environmental impacts like deforestation) have argued that we shouldn’t focus too much on Brazilian deforestation in the Amazon and elsewhere. As long as Brazilians get richer, their impact on Brazil’s pristine forests will gradually lessen.

Many critics have said that Brazil invalidates the EKC theory, citing the rapid increase in deforestation in the Amazon. Despite being much richer in terms of GDP per-capita than other top deforesters (Angola, Tanzania, DRC, Mozambique, Bolivia, Indonesia), Brazil nearly doubled its deforested area in recent years– from 457,000 hectares in 2012 to 1,012,900 hectares in 2019.

What that criticism overlooks is that Brazil is a deeply unequal country, regionally and economically. Its rich southern states have income levels on par with many European countries, whereas the North and Northwest – where most of the forests are – are closer to income levels in sub-Saharan Africa. Indeed, Pará, one of Brazil’s poorest states and equal to Namibia or Indonesia in per-capita income, is almost entirely responsible for Brazil’s increased deforestation rate in the last few years.

The shift of the last decade – from South America as the primary source of deforestation to Africa has been overlooked, as has the decade-by-decade decline in deforestation rates. Despite the much-publicized news about fires in the Amazon, most deforestation now takes place in Africa. This isn’t surprising, as Africa is the poorest continent, and we know that poverty often means living off the land and cutting down forests for fuel. Similarly, the latest UN reports show us that deforestation is a poverty story, not a story about bad regional politics or market failures.

In contrast to the many negative stories about rainforests, the latest deforestation numbers are a reason to rejoice. And here’s my prediction: the next time the GFRA publishes aggregate data, we will see still lower deforestation rates, perhaps even zero. Gradually, but steadily, the Environmental Kuznets Curve is playing out, and the planet is slowly becoming greener.

Blog Post | Urbanization

Lessons From Adam Smith’s Edinburgh and Paris

Examining the places where major advances happened is one way to learn about the conditions that foster societal flourishing, human achievement, and prosperity.

Summary: Amidst the turmoil of modern times, evidence reveals significant progress across various metrics, from rising life expectancy to declining global poverty. Cities have emerged as epicenters of innovation and progress throughout history, fostering collaboration, competition, and freedom of thought. By exploring the unique environments of cities like Edinburgh and Paris, where intellectual liberty thrived, Chelsea Follett uncovers the vital role of peace, freedom, and population density in driving human achievement and societal advancement.

This article appeared in Adam Smith Works on 2/8/2024.

Has humanity made progress? With so many serious problems, it is easy to get the impression that our species is hopeless. Many people view history as one long tale of decay and degeneration since some lost, idealized golden age.

But there has been much remarkable, measurable improvement—from rising life expectancy and literacy rates to declining global poverty. (Explore the evidence for yourself). Today, material abundance is more widespread than our ancestors could have dreamed. And there has been moral progress too. Slavery and torture, once widely accepted, are today almost universally reviled.

Where did all this progress come from? Certain places, at certain times in history, have contributed disproportionately to progress and innovation. Change is a constant, but progress is not. Studying the past may hold the secret to fostering innovation in the present. To that end, I wrote a book titled Centers of Progress: 40 Cities that Changed the World, exploring the places that shaped modern life.

The origin points of the ideas, discoveries, and inventions that built the modern world were far from evenly or randomly dispersed throughout the globe. Instead, they tended to emerge from cities, even in time periods when most of the human population lived in rural areas. In fact, even before anything that could be called a city by modern standards existed, progress originated from the closest equivalents that did exist at the time. Why is that?

“Cities, the dense agglomerations that dot the globe, have been engines of innovation since Plato and Socrates bickered in an Athenian marketplace,” urban economist Edward Glaeser opined in his book The Triumph of the City. Of course, he was hardly the first to observe that positive change often emanates from cities. As Adam Smith noted in 1776, “the commerce and manufactures of cities, instead of being the effect, have been the cause and occasion of the improvement and cultivation of the country.”

One of the reasons that progress tends to emerge from cities is, simply, people. Wherever more people gather together to “truck, barter, and exchange,” in Smith’s words, that increases their potential to engage in productive exchange, discussion, debate, collaboration, and competition with each other. Cities’ higher populations allow for a finer division of labor, more specialization, and greater efficiencies in production. Not to mention, more minds working together to solve problems. As the writer Matt Ridley notes in the foreword he kindly wrote for Centers of Progress, “Progress is a team sport, not an individual pursuit. It is a collaborative, collective thing, done between brains more than inside them.”

A higher population is sufficient to explain why progress often emerges from cities, but, of course, not all cities become major innovation centers. Progress may be a team sport, but why do certain cities seem to provide ideal playing conditions, and not others?

That brings us to the next thing that most centers of progress share, besides being relatively populous: peace. That makes sense, because if a place is plagued by violence and discord then it is hard for the people there to focus on anything other than survival, and there is little incentive to be productive since any wealth is likely to be looted or destroyed. Smith recognized this truth, and noted that cities, historically, sometimes offered more security from violence than the countryside:

Order and good government, and along with them the liberty and security of individuals, were in this manner established in cities, at a time when the occupiers of land in the country, were exposed to every sort of violence. But men in this defenceless state naturally content themselves with their necessary subsistence; because, to acquire more, might only tempt the injustice of their oppressors. On the contrary, when they are secure of enjoying the fruits of their industry, they naturally exert it to better their condition, and to acquire not only the necessaries, but the conveniencies and elegancies of life. That industry, therefore, which aims at something more than necessary subsistence, was established in cities long before it was commonly practised by the occupiers of land in the country. […] Whatever stock, therefore, accumulated in the hands of the industrious part of the inhabitants of the country, naturally took refuge in cities, as the only sanctuaries in which it could be secure to the person that acquired it.

Of course, not all cities were or are peaceful. Consider Smith’s own city: Edinburgh. At times, the city was far from stable. But the relatively unkempt and inhospitable locale emerged from a century of instability to take the world by storm. Scotland in the 18th century had just undergone decades of political and economic turmoil. Disruption was caused by the House of Orange’s ousting of the House of Stuart, the Jacobite Rebellions, the failed and costly colonial Darien Scheme, famine, and the 1707 Union of Scotland and England. It was only after things settled down and the city came to enjoy a period of relative peace and stability that Edinburgh rose to reach its potential. Edinburgh was an improbable center of progress. But Edinburgh proves what people can accomplish, given the right conditions.

During the Scottish Enlightenment centered in Edinburgh, Adam Smith was far from the only innovative thinker in the city. Edinburgh’s ability to cultivate innovators in every arena of human achievement, from the arts to the sciences, seemed almost magical.

Edinburgh gave the world so many groundbreaking artists that the French writer Voltaire opined in 1762 that “today it is from Scotland that we get rules of taste in all the arts, from epic poetry to gardening.” Edinburgh gave humanity artistic pioneers from the novelist Sir Walter Scott, often called the father of the historical novel, to the architect Robert Adam who, together with his brother James, developed the “Adam style,” which evolved into the so‐​called “Federal style” in the United States after Independence.

And then there were the scientists. Thomas Jefferson, in 1789, wrote, “So far as science is concerned, no place in the world can pretend to competition with Edinburgh.” The Edinburger geologist James Hutton developed many of the fundamental principles of his discipline. The chemist and physicist Joseph Black, who studied at the University of Edinburgh, discovered carbon dioxide, magnesium, and the important thermodynamic concepts of latent heat and specific heat. The anatomist Alexander Monro Secondus became the first person to detail the human lymphatic system. Sir James Young Simpson, admitted to the University of Edinburgh at the young age of fourteen, went on to develop chloroform anesthesia.

Two of the greatest gifts that Edinburgh gave humanity were empiricism and economics. The influential philosopher David Hume was among the early advocates of empiricism and is sometimes called the father of philosophical skepticism. And by creating the field of economics, Smith helped humanity to think about policies that enhance prosperity. Those policies, including free trade and economic freedom that Smith advocated, have since helped to raise living standards to heights that would be unimaginable to Smith and his contemporaries.

That brings us to the last but by no means least secret ingredient of progress. Freedom. Centers of progress during their creative peak tend to be relatively free and open for their era. That makes sense because simply having a large population is not going to lead to progress if that population lacks the freedom to experiment, to debate new propositions, and to work together for their mutual benefit. Perhaps the biggest reason why cities produce so much progress is that city dwellers have often enjoyed more freedom than their rural counterparts. Medieval serfs fleeing feudal lands to gain freedom in cities inspired the German saying “stadtluft macht frei” (city air makes you free).

That adage referred to laws granting serfs liberty after a year and a day of urban residency. But the phrase arguably has a wider application. Cities have often served as havens of freedom for innovators and anyone stifled by the stricter norms and more limited choices common in smaller communities. Edinburgh was notable for its atmosphere of intellectual freedom, allowing thinkers to debate a wide diversity of controversial ideas in its many reading societies and pubs.

Of course, cities are not always free. Authoritarian states sometimes see laxer enforcement of their draconian laws in remote areas, and Smith himself viewed rural life as in some ways less encumbered by constraining rules and regulations than city life. But as philosophy professor Kyle Swan previously noted for Adam Smith Works:

Without denying the charms and attractions Smith highlights in country living, let’s not forget what’s on offer in our cities: a significantly broader range of choices! Diverse restaurants and untold many other services and recreations, groups of people who like the same peculiar things that you like, and those with similar backgrounds and interests and activities to pursue with them — cities are (positive) freedom enhancing.

The same secret ingredients of progress—people, peace, and freedom—that helped Edinburgh to flourish during Smith’s day can be observed again and again throughout history in the places that became key centers of innovation. Consider Paris.

As the capital of France, Paris attracted a large population and became an important economic and cultural hub. But it was an unusual spirit of freedom that allowed the city to make its greatest contributions to human progress. Much like the reading societies and pubs of Smith’s Edinburgh, the salons and coffeehouses of 18th‐​century Paris provided a place for intellectual discourse where the philosophes birthed the so‐​called Age of Enlightenment.

The Enlightenment was a movement that promoted the values of reason, evidence‐​based knowledge, free inquiry, individual liberty, humanism, limited government, and the separation of church and state. In Parisian salons, nobles and other wealthy financiers intermingled with artists, writers, and philosophers seeking financial patronage and opportunities to discuss and disseminate their work. The gatherings gave controversial philosophers, who would have been denied the intellectual freedom to explore their ideas elsewhere, the liberty to develop their thoughts.

Influential Parisian and Paris‐ based thinkers of the period included the Baron de Montesquieu, who advocated the then‐​groundbreaking idea of the separation of government powers and the writer Denis Diderot, the creator of the first general‐​purpose encyclopedia, as well the Genevan expat Jean‐​Jacques Rousseau. While sometimes considered a counter‐​Enlightenment figure because of his skepticism of modern commercial society and romanticized view of primitive existence, Rousseau also helped to spread skepticism toward monarchy and the idea that kings had a “divine right” to rule over others.

The salons were famous for sophisticated conversations and intense debates; however, it was letter‐​writing that gave the philosophes’ ideas a wide reach. A community of intellectuals that spanned much of the Western world—known as the Republic of Letters—increasingly engaged in the exchanges of ideas that began in Parisian salons. Thus, the Enlightenment movement based in Paris helped spur similar radical experiments in thought elsewhere, including the Scottish Enlightenment in Edinburgh. Smith’s many exchanges of ideas with the people of Paris, including during his 1766 visit to the city when he dined with Diderot and other luminaries, proved pivotal to his own intellectual development.

And then there was Voltaire, sometimes called the single most influential figure of the Enlightenment. Although Parisian by birth, Voltaire spent relatively little time in Paris because of frequent exiles occasioned by the ire of French authorities. Voltaire’s time hiding out in London, for example, enabled him to translate the works of the political philosopher and “father of liberalism” John Locke, as well as the English mathematician and physicist Isaac Newton. While Voltaire’s critiques of existing institutions and norms pushed the boundaries of acceptable discourse beyond even what would be tolerated in Paris, his Parisian upbringing and education likely helped to cultivate the devotion to freethinking that would come to define his life.

By allowing for an unusual degree of intellectual liberty and providing a home base for the Enlightenment and the far‐​ranging Republic of Letters, Paris helped spread new ideas that would ultimately give rise to new forms of government—including modern liberal democracy.

Surveying the cities, such as Edinburgh and Paris, that built the modern world reveals that when people live in peace and freedom, their potential to bring about positive change increases. Examining the places where major advances happened is one way to learn about the conditions that foster societal flourishing, human achievement, and prosperity. I hope that you will consider joining me on a journey through the book’s pages to some of history’s greatest centers of progress, and that doing so sparks many intelligent discussions, debates, and inquiries in the Smithian tradition about the causes of progress and wealth.

Blog Post | Human Development

1,000 Bits of Good News You May Have Missed in 2023

A necessary balance to the torrent of negativity.

Reading the news can leave you depressed and misinformed. It’s partisan, shallow, and, above all, hopelessly negative. As Steven Pinker from Harvard University quipped, “The news is a nonrandom sample of the worst events happening on the planet on a given day.”

So, why does Human Progress feature so many news items? And why did I compile them in this giant list? Here are a few reasons:

  • Negative headlines get more clicks. Promoting positive stories provides a necessary balance to the torrent of negativity.
  • Statistics are vital to a proper understanding of the world, but many find anecdotes more compelling.
  • Many people acknowledge humanity’s progress compared to the past but remain unreasonably pessimistic about the present—not to mention the future. Positive news can help improve their state of mind.
  • We have agency to make the world better. It is appropriate to recognize and be grateful for those who do.

Below is a nonrandom sample (n = ~1000) of positive news we collected this year, separated by topic area. Please scroll, skim, and click. Or—to be even more enlightened—read this blog post and then look through our collection of long-term trends and datasets.



Farming robots and drones

Food abundance

Genetic modification

Indoor farming

Lab-grown produce


Other innovations

Conservation and Biodiversity

Big cats




Other comebacks



Rivers and lakes

Surveillance and discovery

Rewilding and conservation


Culture and tolerance

Gender equality

General wellbeing


Treatment of animals

Energy and natural Resources



Fossil fuels

Other energy

Recycling and resource efficiency

Resource abundance

Environment and pollution

Climate change

Disaster resilience

Air pollution

Water pollution

Growth and development


Economic growth

Housing and urbanization

Labor and employment



Disability and assistive technology

Dementia and Alzheimer’s


Heart disease and stroke

Other non-communicable diseases



Other communicable diseases

Maternal care

Fertility and birth control

Mental health and addiction

Weight and nutrition

Longevity and mortality 

Surgery and emergency medicine

Measurement and imaging

Health systems

Other innovations



    Artificial intelligence



    Construction and manufacturing


    Robotics and automation

    Autonomous vehicles


    Other innovations


    AI in science


    Chemistry and materials






      Afrik 21 | Housing

      A Reduction in the Proportion of Africans Living in Shanty Towns

      “According to the United Nations Development Programme (UNDP), a shanty town is a disadvantaged part of a city characterised by very unhealthy housing built by the inhabitants from salvaged materials, extreme poverty and no rights or security of tenure. According to the World Bank, over 60% of Africa’s urban population now lives in shanty towns. These almost 285 million urban dwellers represent 60% of Africa’s urban population. In 2003, Africans living in shanty towns made up 71.9% of the urban population.”

      From Afrik 21.

      Blog Post | Urbanization

      Introducing Centers of Progress: 40 Cities That Changed the World

      “Cities, the dense agglomerations that dot the globe, have been engines of innovation since Plato and Socrates bickered in an Athenian marketplace,” as urban economist Edward Glaeser explains in his book The Triumph of the City.

      Athens’s storied breakthroughs in philosophy are but one example of how cities have often been the sites of pivotal advances throughout history. Kyoto gave us the novel. Bologna gave us the university. Florence gave us the Renaissance. Paris gave us the Enlightenment. Manchester gave us the Industrial Revolution. Los Angeles gave us cinema. Postwar New York gave us modern finance . . . the list goes on. As Glaeser also notes, “Wandering these cities—whether down cobblestone sidewalks or grid-cutting cross streets, around roundabouts or under freeways—is to study nothing less than human progress.”

      If you’re not able to travel to each of these extraordinary cities, perhaps the next best thing is to embark on a virtual tour from the comfort of your home. To that end, I wrote a book surveying 40 of history’s greatest urban centers, showcasing each city at a moment in time when it notably contributed to progress.

      Centers of Progress: 40 Cities That Changed the World offers a fact-filled yet accessible crash course in global urban history, spanning from the agricultural revolution to the digital revolution. This book affirms the importance of cities to the story of human progress and innovation by shining a spotlight on some of the places that have helped create the modern world.

      The book’s chapters can guide you through the Library of Alexandria, the stock exchange of Dutch Golden Age-era Amsterdam, and the pubs of Edinburgh during the Scottish Enlightenment, all in an afternoon.

      Centers of Progress “takes the reader on a time-travel cruise through the great flash points of human activity to catch innovations that have transformed human lives” at their moment of invention, according to writer Matt Ridley in the insightful foreword that he kindly provided. Come explore Agra as the Taj Mahal was erected and Cambridge as Isaac Newton penned the Principia. Meet engineers in Ancient Rome, Silk Road merchants in Tang Dynasty Chang’an, music composers in 19th-century Vienna, and Space Age flight controllers in Houston.

      Learning about past achievements may even hold the secret to fostering innovation in the present.

      As I note in the book, “Although there are some exceptions, most cities reach their creative peak during periods of peace. Most centers of progress also thrive during times of relative social, intellectual, and economic freedom, as well as openness to intercultural exchange and trade. And centers of progress tend to be highly populated. . . . Identifying those common denominators among the places that have produced history’s greatest achievements is one way to learn what causes progress in the first place. After all, change is a constant, but progress is not.”

      From the fall of the Berlin Wall to Hong Kong’s transformation from a war-ravaged “barren island” into a prosperous metropolis, many of the stories featured in Centers of Progress hold valuable lessons about the importance of ideas, people, and freedom. I hope that you will consider joining me on a journey through the book’s pages to some of history’s greatest centers of progress.