Simulated image of the Earth from the Moon, Courtesy NASA.
A Planetary Perspective by Dr. Jonathan Foley
This moment in history demands a new way of seeing the world. We must mature as a civilization, learn from the natural world around us, and start seeing ourselves as stewards of the planet, learning to thrive while respecting Earth’s physical and biological realities.
“Viewed from the distance of the moon, the astonishing thing about the earth, catching the breath, is that it is alive. The photographs show the dry, pounded surface of the moon in the foreground, dead as an old bone. Aloft, floating free beneath the moist, gleaming membrane of bright blue sky, is the rising earth, the only exuberant thing in this part of the cosmos. If you could look long enough, you would see the swirling of the great drifts of cloud, covering and uncovering the half-hidden masses of land. If you had been looking a very long, geologic time, you could have seen the continents themselves in motion, drifting apart on their crustal plates, held aloft by the fire beneath. It has the organized, self-contained look of a live creature, full of information, marvelously skilled in handling the sun.” — Lewis Thomas, Lives of a Cell
There is an apocryphal saying, often called the Ancient Chinese Curse, which says, “May you live in interesting times...”
This time certainly qualifies. In fact, I think that this is the most crucial moment in human history, unlike anything we have ever seen before.
And we’ve been around a long time. Creatures like us — modern humans, early hominids, and our other ancient ancestors — have walked this planet for millions of years. And during almost all of that time, for hundreds of thousands of generations, one fact was undeniably true: We were small, and the Earth was big. Very big. In fact, to us, the planet was essentially infinite, with endless space and resources.
For countless millennia, we could collect food and fuel, drink from local waters, hunt and fish the creatures around us, and pollute our immediate surroundings — all without making much of a dent in the planet. Economist Herman Daly called this the “Empty World” time in our history, when Earth’s resources were plentiful, vast frontiers still existed, and the global environment was largely unaffected by human impact. Even as we invented fire, simple tools, the wheel, early agriculture, and the first cities, we could thrive, multiply, and spread out, without dramatic consequences for the planet as a whole. But all that changed in the last few decades, and the world would never be the same.
Today, you cannot escape seeing our tremendous impact across the planet. It’s visible everywhere. Even from orbit, you can see extensive networks of roads and city lights, vast areas of forest clearing, massive tracts of farmland and industrialized agriculture, dried-up lakes and inland seas, and polluted rivers and coastlines. We also see that many species, and even entire ecological systems, are now gone from the world — all due to our impact. And perhaps most unsettling: Our actions have started to change the chemistry and physics of the planet, already causing the early signs of climate change, sea level rise, and ocean acidification. Today, no part of the planet — whether the upper atmosphere, the most remote jungles, the polar ice fields, or the deepest ocean — has escaped our influence.
Suddenly, we shifted from an “Empty World,” largely devoid of human impact, to a “Full World,” radically impacted by human activity.
What caused this sudden change? We did — through a sudden burst of human activity, called the “Great Acceleration,” fueled by rapidly growing population, economic activity, technology, and resource use.
Let’s look at the changes of the last fifty years. First of all, global population increased from ~3.7 billion in 1970 to ~7.7 billion today — a ~2.1x increase. The world’s population will continue to rise, but at a slowing rate, and is expected to peak at somewhere between 9 and 10 billion later in the century. During the same time, the world’s total economic activity (adjusted to current US dollors) increased from 15.6 trillion in 1970 to roughly $84 trillion today — or a ~5.5x increase.
That’s twice as many people, doing more than five times more economic activity — in only fifty years.
During the same fifty years, global food consumption increased by roughly ~3x — mostly from the ~2.1x increase in the world’s population, but also from a ~1.3x increase in calorie consumption per capita. With it, global fertilizer use increased roughly four-fold, and global water consumption, mostly for irrigating crops, increased by ~1.8x. And global energy consumption, mostly in the form of fossil fuels like oil, coal, and natural gas, increased by almost ~3x.
Not only are more people alive today, engaged in far more economic activity, using more resources than ever, but the nature of our lives has changed fundamentally. We live much longer and healthier lives than any generation before us. Global average life expectancy in 1970 was roughly ~55 years; today it is over 71 years, the longest in human history. We also have smaller families: Around 1970, the average woman on Earth had over five children; today she has 2.4, and falling fast.
We have also become more urban than ever, with the majority of our population now living in cities for the first time in human history. Roughly 55% of the world’s population now lives in an urban area, up from roughly 35% fifty years ago. We have also become far more mobile and connected.
We are also far more literate than at any time in human history. Back in 1900, only ~20% of the world’s population was literate. In 1970, the world was ~50% literate. Today we are ~85% literate.
And to many people’s surprise, we are probably safer than ever. Steven Pinker argues that we may be living in the most peaceful period in human history, after long-term declines in death from violence and warfare.
Just think about this for a second: During the last 50 years, we doubled the world’s population, grew our economic activity almost six-fold, and started using two to three times more global resources than ever before. Put another way, our society changed more in the last fifty years than in any other time in history. More startling, we changed more in the last 50 years than in the entirety of human existence.
Whether we like it or not, we are an inflection point in our history. Everything has changed. Even the way we change has changed.
Our rapid transition from an “Empty World” to a “Full World” has profoundly reshaped us and our civilization. And despite much of the gloom and doom talk of our era, many of those changes have been good for us — at least in the short run. We currently live longer, healthier, and safer lives than any previous human generation. We are also more literate, more urban, more mobile, and more connected than anyone in history. And our technological power is growing exponentially. In many ways, people alive today are living some of the best lives in human history.
But, no matter the benefits to people alive today, our suddenly reaching humanity’s inflection point has greatly impacted the planet, and has put Earth’s key environmental systems — and our children — at risk.
How have we changed the global environment?
Perhaps the most obvious sign of our global impact is how we altered landscapes across the planet. While we have always shaped the land around us, the sheer reach and magnitude of our impact today is breathtaking. We have now cleared or converted 35–40% of the Earth’s entire land surface, an area bigger than South America and Africa combined, almost entirely for agriculture.
This clearing of land has caused the loss of habitats, the extinction of countless species, and the degradation of soils and watersheds in many regions. Beyond the wholesale clearing or conversion of land, we have also changed the nature of our remaining forests, savannas, grasslands, and deserts by building roads, harvesting trees, mining for oil and minerals, and introducing invasive species. Today, there is no landscape on the planet that hasn’t felt our impact.
Agriculture now dominates the world’s land surface. In total, croplands and pastures cover about 37% of the world’s land area (see Foley et al., 2011, for more details). And most of this agricultural land, roughly 75% of it, is devoted to animal agriculture — either as grazing land or land devoted to growing animal feed.
We have also changed Earth’s water cycle, altering the amount, timing, and quality of freshwater flowing across Earth’s continents to the sea. Until recently, Earth’s water flowed naturally, uninterrupted, without pollution, through river networks and groundwater systems connecting land to ocean. But now humans operate nearly 32,000 large dams worldwide, almost tripling the number we had fifty years ago, as well as operating countless wells that extract water from aquifers. This allows us to divert and extract 4,000 cubic kilometers of freshwater from their natural flows each year. The vast majority of this use is for agriculture and industry, and it often exceeds nature’s ability to replenish water, leaving behind dried-up aquifers, rivers, lakes, and even inland seas behind.
The decline of the Aral Sea in central Asia, caused by diverting the region’s major rivers to irrigate the deserts of Kazakhstan. Images courtesy of NASA.
Not only have we changed the quantity and timing of Earth’s water flows, we have also polluted many of Earth’s waterways, whether from untreated human waste (which is still an issue in developing nations), industrial toxins, or widespread agricultural runoff. Earth’s water, the most important ingredient for life and weather, is changing from our actions.
And we have even changed the sky itself. The burning of fossil fuels, as well as the ongoing clearing of tropical forests and some agricultural practices, all release greenhouse gasses. And we know that these increasing greenhouse gasses trap heat in the atmosphere, leading to growing levels of climate change, with warmer temperatures and increasing weather extremes all around the world.
Moreover, the combination of melting ice and warmer oceans has led to accelerating sea level rise, which could cause trouble for coastal regions of the planet in the coming decades. Beyond the impacts of greenhouse gasses on our climate, carbon dioxide also dissolves in sea water, contributing to ocean acidification, which could have negative effects on marine life, especially corals and shellfish.
Should we be concerned about our impacts on the global environment? After all, the planet has changed before, and life endured. In fact, over geologic time, we’ve seen ice ages come and go, asteroid impacts, continents adrift, and the rise of entirely new forms of life. Over millions and billions of years, change has been the only constant feature of our planet. And life persisted through it all.
So, if the environment has changed before, and life persisted, should we be all that worried about new, human-induced impacts?
In a word: Yes, because this time it’s different. Very different.
First of all, this is the first time the planet is undergoing major change while human civilization existed. We modern humans have never been through a planetary-scale environmental disruption before. And the previous ones, whether from asteroid impacts or ice ages, weren’t very kind to other life forms. Just ask the dinosaurs.
And, unlike environmental changes of the past, this environmental disaster isn’t caused by an asteroid, a change in our orbit around the sun, or a super-volcano. It’s caused by a single, supposedly intelligent, form of life: Us.
In fact, today’s planet is so radically changed scientists often refer to this as a new geologic epoch — the Anthropocene, the human-dominated era of Planet Earth, where civilization replaced geology as the dominant factor driving the planet. For the previous ten thousand years, we were in the relatively stable Holocene epoch, and now, suddenly, we are in the Anthropocene. Time to change the calendars.
Unlike other periods of human history, the Anthropocene is witnessing the impacts of human activity on the entire planetary environment, not just our immediate local surroundings. And the future of our planet will be determined by our choices.
Finally, the speed and scope of these disruptions is breathtaking. We are fundamentally changing the planet’s ecosystems, natural resources, and climate system at the same time, in the matter of a few decades. I can’t honestly see any parallel in Earth’s recent geologic history. We are entering uncharted territory.
In fact, scientists have started to track recent changes in the global environment using a new “Planetary Boundaries” framework. (Full disclosure: I was a co-author on the original paper in Nature that proposed it.) This framework tracks how the planet is changing along several dimensions — such as the concentration of greenhouse gasses in the atmosphere, the amount of land cleared, the amount of water consumed, the acidification of the ocean, and so on — compared to Earth’s recent geologic experience. If the changes are small, compared to the last 10,000 years of human civilization, they are considered “safe”. But if they start to go far beyond those values, beyond anything we our civilization has seen before, they are increasingly of concern, and potentially dangerous. Right now, the planetary boundaries framework says there are 3 areas of “high risk” (biosphere integrity, nitrogen flows, phosphorus flows) and two of “increasing risk” (climate change, land system change).
Planetary Boundaries framework, which tracks how the planet is changing along several dimensions — including the concentration of greenhouse gasses in the atmosphere, the amount of land cleared, the amount of water consumed, the acidification of the ocean, and so on — compared to Earth’s recent geologic history. Image credit: J. Lokrantz / Azote, based on Steffen et al., 2015.
In short, it’s a perfect storm of global environmental issues. And it’s happening on our watch.
And that’s a big worry. A series of rapid, multi-faceted changes to the global environment — for the first time since modern civilization began — is likely to be highly disruptive to us. After all, we are talking about environmental changes that will affect where our food is grown, and how much; how much water we have, and when; what our weather patterns are like, and who may experience stronger storms; where our sea levels are, and which cities and island nations may need to be evacuated; and even the ecosystems and species we share the planet with. These changes in the environment aren’t just important to birds, butterflies, and polar bears: unchecked, they could come to undermine our health, safety, prosperity, and security too.
In short, if we don’t tackle these issues, we will be leaving a giant mess to our children and grandchildren.
Dr.Jonathan Foley(@GlobalEcoGuy) is a climate & environmental scientist, writer, and speaker. He is also the Executive Director ofProject Drawdown, the world’s leading resource for climate solutions.
xiewei18
commented
11 months ago
Simulated image of the Earth from the Moon, Courtesy NASA.
A Planetary Perspective by Dr. Jonathan Foley
This moment in history demands a new way of seeing the world. We must mature as a civilization, learn from the natural world around us, and start seeing ourselves as stewards of the planet, learning to thrive while respecting Earth’s physical and biological realities.
There is an apocryphal saying, often called the Ancient Chinese Curse, which says, “May you live in interesting times...”
This time certainly qualifies. In fact, I think that this is the most crucial moment in human history, unlike anything we have ever seen before.
And we’ve been around a long time. Creatures like us — modern humans, early hominids, and our other ancient ancestors — have walked this planet for millions of years. And during almost all of that time, for hundreds of thousands of generations, one fact was undeniably true: We were small, and the Earth was big. Very big. In fact, to us, the planet was essentially infinite, with endless space and resources.
For countless millennia, we could collect food and fuel, drink from local waters, hunt and fish the creatures around us, and pollute our immediate surroundings — all without making much of a dent in the planet. Economist Herman Daly called this the “Empty World” time in our history, when Earth’s resources were plentiful, vast frontiers still existed, and the global environment was largely unaffected by human impact. Even as we invented fire, simple tools, the wheel, early agriculture, and the first cities, we could thrive, multiply, and spread out, without dramatic consequences for the planet as a whole. But all that changed in the last few decades, and the world would never be the same.
Today, you cannot escape seeing our tremendous impact across the planet. It’s visible everywhere. Even from orbit, you can see extensive networks of roads and city lights, vast areas of forest clearing, massive tracts of farmland and industrialized agriculture, dried-up lakes and inland seas, and polluted rivers and coastlines. We also see that many species, and even entire ecological systems, are now gone from the world — all due to our impact. And perhaps most unsettling: Our actions have started to change the chemistry and physics of the planet, already causing the early signs of climate change, sea level rise, and ocean acidification. Today, no part of the planet — whether the upper atmosphere, the most remote jungles, the polar ice fields, or the deepest ocean — has escaped our influence.
Suddenly, we shifted from an “Empty World,” largely devoid of human impact, to a “Full World,” radically impacted by human activity.
What caused this sudden change? We did — through a sudden burst of human activity, called the “Great Acceleration,” fueled by rapidly growing population, economic activity, technology, and resource use.
Let’s look at the changes of the last fifty years. First of all, global population increased from ~3.7 billion in 1970 to ~7.7 billion today — a ~2.1x increase. The world’s population will continue to rise, but at a slowing rate, and is expected to peak at somewhere between 9 and 10 billion later in the century. During the same time, the world’s total economic activity (adjusted to current US dollors) increased from 15.6 trillion in 1970 to roughly $84 trillion today — or a ~5.5x increase.
That’s twice as many people, doing more than five times more economic activity — in only fifty years.
Historical changes in global population, urban population fraction, and global economic activity on planet Earth, between 1750 and 2020. Data from IGBP Great Acceleration project and datasets. Graphics by Jonathan Foley, Copyright © 2020.
During the same fifty years, global food consumption increased by roughly ~3x — mostly from the ~2.1x increase in the world’s population, but also from a ~1.3x increase in calorie consumption per capita. With it, global fertilizer use increased roughly four-fold, and global water consumption, mostly for irrigating crops, increased by ~1.8x. And global energy consumption, mostly in the form of fossil fuels like oil, coal, and natural gas, increased by almost ~3x.
Not only are more people alive today, engaged in far more economic activity, using more resources than ever, but the nature of our lives has changed fundamentally. We live much longer and healthier lives than any generation before us. Global average life expectancy in 1970 was roughly ~55 years; today it is over 71 years, the longest in human history. We also have smaller families: Around 1970, the average woman on Earth had over five children; today she has 2.4, and falling fast.
We have also become more urban than ever, with the majority of our population now living in cities for the first time in human history. Roughly 55% of the world’s population now lives in an urban area, up from roughly 35% fifty years ago. We have also become far more mobile and connected.
We are also far more literate than at any time in human history. Back in 1900, only ~20% of the world’s population was literate. In 1970, the world was ~50% literate. Today we are ~85% literate.
And to many people’s surprise, we are probably safer than ever. Steven Pinker argues that we may be living in the most peaceful period in human history, after long-term declines in death from violence and warfare.
Just think about this for a second: During the last 50 years, we doubled the world’s population, grew our economic activity almost six-fold, and started using two to three times more global resources than ever before. Put another way, our society changed more in the last fifty years than in any other time in history. More startling, we changed more in the last 50 years than in the entirety of human existence.
Whether we like it or not, we are an inflection point in our history. Everything has changed. Even the way we change has changed.
Photo by NASA on Unsplash
Our rapid transition from an “Empty World” to a “Full World” has profoundly reshaped us and our civilization. And despite much of the gloom and doom talk of our era, many of those changes have been good for us — at least in the short run. We currently live longer, healthier, and safer lives than any previous human generation. We are also more literate, more urban, more mobile, and more connected than anyone in history. And our technological power is growing exponentially. In many ways, people alive today are living some of the best lives in human history.
But, no matter the benefits to people alive today, our suddenly reaching humanity’s inflection point has greatly impacted the planet, and has put Earth’s key environmental systems — and our children — at risk.
How have we changed the global environment?
Perhaps the most obvious sign of our global impact is how we altered landscapes across the planet. While we have always shaped the land around us, the sheer reach and magnitude of our impact today is breathtaking. We have now cleared or converted 35–40% of the Earth’s entire land surface, an area bigger than South America and Africa combined, almost entirely for agriculture.
This clearing of land has caused the loss of habitats, the extinction of countless species, and the degradation of soils and watersheds in many regions. Beyond the wholesale clearing or conversion of land, we have also changed the nature of our remaining forests, savannas, grasslands, and deserts by building roads, harvesting trees, mining for oil and minerals, and introducing invasive species. Today, there is no landscape on the planet that hasn’t felt our impact.
Historical changes in global land use for agriculture, tropical forest loss, large dams construction, and global water use on planet Earth, between 1750 and 2020. Data from IGBP Great Acceleration project and datasets. Graphics by Jonathan Foley, Copyright © 2020.
Agriculture now dominates the world’s land surface. In total, croplands and pastures cover about 37% of the world’s land area (see Foley et al., 2011, for more details). And most of this agricultural land, roughly 75% of it, is devoted to animal agriculture — either as grazing land or land devoted to growing animal feed.
We have also changed Earth’s water cycle, altering the amount, timing, and quality of freshwater flowing across Earth’s continents to the sea. Until recently, Earth’s water flowed naturally, uninterrupted, without pollution, through river networks and groundwater systems connecting land to ocean. But now humans operate nearly 32,000 large dams worldwide, almost tripling the number we had fifty years ago, as well as operating countless wells that extract water from aquifers. This allows us to divert and extract 4,000 cubic kilometers of freshwater from their natural flows each year. The vast majority of this use is for agriculture and industry, and it often exceeds nature’s ability to replenish water, leaving behind dried-up aquifers, rivers, lakes, and even inland seas behind.
The decline of the Aral Sea in central Asia, caused by diverting the region’s major rivers to irrigate the deserts of Kazakhstan. Images courtesy of NASA.
Not only have we changed the quantity and timing of Earth’s water flows, we have also polluted many of Earth’s waterways, whether from untreated human waste (which is still an issue in developing nations), industrial toxins, or widespread agricultural runoff. Earth’s water, the most important ingredient for life and weather, is changing from our actions.
Historical changes in global fertilizer use, estimated nitrogen flows to the ocean, marine fishing, and global aquaculture on planet Earth, between 1750 and 2020. Data from IGBP Great Acceleration project and datasets. Graphics by Jonathan Foley, Copyright © 2020.
And we have even changed the sky itself. The burning of fossil fuels, as well as the ongoing clearing of tropical forests and some agricultural practices, all release greenhouse gasses. And we know that these increasing greenhouse gasses trap heat in the atmosphere, leading to growing levels of climate change, with warmer temperatures and increasing weather extremes all around the world.
Photo by Hassan Maayiz on Unsplash
Historical changes in global energy use and tropical forest loss, between 1750 and 2020, and the resulting increases in greenhouse gases — including carbon dioxide, methane, and nitrous oxide in Earth’s atmosphere . Data from IGBP Great Acceleration datasets. Graphics by Jonathan Foley, Copyright © 2020.
Since the mid-nineteenth century, the levels of carbon dioxide increased by roughly 50%, due to human activities — including burning fossil fuels, deforestation, and other industrial chemical emissions. Carbon dioxide is one of a family of “greenhouse gases” that humans have increased in the atmosphere, causing significant warming to the planet. Graphics by Jonathan Foley, Copyright © 2020.
Since the mid-nineteenth century, the planet has warmed — on average — roughly 1˚C. If we continue to emit high levels of greenhouse gases, the planet will warm even more, and cause widespread disruption to the climate and environment of this planet. Graphics by Jonathan Foley, Copyright © 2020.
Moreover, the combination of melting ice and warmer oceans has led to accelerating sea level rise, which could cause trouble for coastal regions of the planet in the coming decades. Beyond the impacts of greenhouse gasses on our climate, carbon dioxide also dissolves in sea water, contributing to ocean acidification, which could have negative effects on marine life, especially corals and shellfish.
Should we be concerned about our impacts on the global environment? After all, the planet has changed before, and life endured. In fact, over geologic time, we’ve seen ice ages come and go, asteroid impacts, continents adrift, and the rise of entirely new forms of life. Over millions and billions of years, change has been the only constant feature of our planet. And life persisted through it all.
So, if the environment has changed before, and life persisted, should we be all that worried about new, human-induced impacts?
In a word: Yes, because this time it’s different. Very different.
First of all, this is the first time the planet is undergoing major change while human civilization existed. We modern humans have never been through a planetary-scale environmental disruption before. And the previous ones, whether from asteroid impacts or ice ages, weren’t very kind to other life forms. Just ask the dinosaurs.
And, unlike environmental changes of the past, this environmental disaster isn’t caused by an asteroid, a change in our orbit around the sun, or a super-volcano. It’s caused by a single, supposedly intelligent, form of life: Us.
Photo by Adrian Schwarz on Unsplash
In fact, today’s planet is so radically changed scientists often refer to this as a new geologic epoch — the Anthropocene, the human-dominated era of Planet Earth, where civilization replaced geology as the dominant factor driving the planet. For the previous ten thousand years, we were in the relatively stable Holocene epoch, and now, suddenly, we are in the Anthropocene. Time to change the calendars.
Unlike other periods of human history, the Anthropocene is witnessing the impacts of human activity on the entire planetary environment, not just our immediate local surroundings. And the future of our planet will be determined by our choices.
Finally, the speed and scope of these disruptions is breathtaking. We are fundamentally changing the planet’s ecosystems, natural resources, and climate system at the same time, in the matter of a few decades. I can’t honestly see any parallel in Earth’s recent geologic history. We are entering uncharted territory.
In fact, scientists have started to track recent changes in the global environment using a new “Planetary Boundaries” framework. (Full disclosure: I was a co-author on the original paper in Nature that proposed it.) This framework tracks how the planet is changing along several dimensions — such as the concentration of greenhouse gasses in the atmosphere, the amount of land cleared, the amount of water consumed, the acidification of the ocean, and so on — compared to Earth’s recent geologic experience. If the changes are small, compared to the last 10,000 years of human civilization, they are considered “safe”. But if they start to go far beyond those values, beyond anything we our civilization has seen before, they are increasingly of concern, and potentially dangerous. Right now, the planetary boundaries framework says there are 3 areas of “high risk” (biosphere integrity, nitrogen flows, phosphorus flows) and two of “increasing risk” (climate change, land system change).
Planetary Boundaries framework, which tracks how the planet is changing along several dimensions — including the concentration of greenhouse gasses in the atmosphere, the amount of land cleared, the amount of water consumed, the acidification of the ocean, and so on — compared to Earth’s recent geologic history. Image credit: J. Lokrantz / Azote, based on Steffen et al., 2015.
In short, it’s a perfect storm of global environmental issues. And it’s happening on our watch.
And that’s a big worry. A series of rapid, multi-faceted changes to the global environment — for the first time since modern civilization began — is likely to be highly disruptive to us. After all, we are talking about environmental changes that will affect where our food is grown, and how much; how much water we have, and when; what our weather patterns are like, and who may experience stronger storms; where our sea levels are, and which cities and island nations may need to be evacuated; and even the ecosystems and species we share the planet with. These changes in the environment aren’t just important to birds, butterflies, and polar bears: unchecked, they could come to undermine our health, safety, prosperity, and security too.
In short, if we don’t tackle these issues, we will be leaving a giant mess to our children and grandchildren.
Photo by Rene Bernal on Unsplash
Please read Part 2 of this article here.
Dr. Jonathan Foley (@GlobalEcoGuy) is a climate & environmental scientist, writer, and speaker. He is also the Executive Director of Project Drawdown, the world’s leading resource for climate solutions.
These views are his own.
Copyright © 2015–2020, Jonathan Foley. All rights reserved.