How to Feed the World
By Jessica Eise and Ken Foster
()
About this ebook
How to Feed the World unites contributors from different perspectives and academic disciplines, ranging from agronomy and hydrology to agricultural economy and communication. Hailing from Germany, the Philippines, the U.S., Ecuador, and beyond, the contributors weave their own life experiences into their chapters, connecting global issues to our tangible, day-to-day existence. Across every chapter, a similar theme emerges: these are not simple problems, yet we can overcome them. Doing so will require cooperation between farmers, scientists, policy makers, consumers, and many others.
The resulting collection is an accessible but wide-ranging look at the modern food system. Readers will not only get a solid grounding in key issues, but be challenged to investigate further and contribute to the paramount effort to feed the world.
Related to How to Feed the World
Related ebooks
Gray to Green Communities: A Call to Action on the Housing and Climate Crises Rating: 4 out of 5 stars4/5Nature-Friendly Communities: Habitat Protection And Land Use Planning Rating: 0 out of 5 stars0 ratingsMaking Healthy Places: Designing and Building for Health, Well-being, and Sustainability Rating: 0 out of 5 stars0 ratingsDesigning Greenways: Sustainable Landscapes for Nature and People, Second Edition Rating: 0 out of 5 stars0 ratingsMaking Healthy Places, Second Edition: Designing and Building for Well-Being, Equity, and Sustainability Rating: 0 out of 5 stars0 ratingsThe Heart of Sustainability: Restoring Ecological Balance from the Inside Out Rating: 0 out of 5 stars0 ratingsLeadership for Sustainability: Strategies for Tackling Wicked Problems Rating: 0 out of 5 stars0 ratingsBuilding Community Food Webs Rating: 0 out of 5 stars0 ratingsA Healthy Nature Handbook: Illustrated Insights for Ecological Restoration from Volunteer Stewards of Chicago Wilderness Rating: 0 out of 5 stars0 ratingsThe Heart of Sustainability: Restoring Ecological Balance from the Inside Out Rating: 0 out of 5 stars0 ratingsFoundations of Restoration Ecology Rating: 0 out of 5 stars0 ratingsThe Significance of Sustainability Rating: 0 out of 5 stars0 ratingsNature's Allies: Eight Conservationists Who Changed Our World Rating: 4 out of 5 stars4/5Intelligent Tinkering: Bridging the Gap between Science and Practice Rating: 0 out of 5 stars0 ratingsCan Business Save the Earth?: Innovating Our Way to Sustainability Rating: 0 out of 5 stars0 ratingsEcological Principles of Landscape Management: Soils and the Processes That Determine Success of Landscape Designs, Farms and Plants Rating: 0 out of 5 stars0 ratingsAgrotopias: An American Literary History of Sustainability Rating: 0 out of 5 stars0 ratingsEffective Conservation: Parks, Rewilding, and Local Development Rating: 0 out of 5 stars0 ratingsOrganic Vegetable Grower: A Practical Guide to Growing for the Market Rating: 0 out of 5 stars0 ratingsUnderstanding Environmental Policy Rating: 0 out of 5 stars0 ratingsAgrarian Dreams: The Paradox of Organic Farming in California Rating: 4 out of 5 stars4/5From the Ground Up: Local Efforts to Create Resilient Cities Rating: 0 out of 5 stars0 ratingsRestoring Ecological Health to Your Land Rating: 0 out of 5 stars0 ratingsGuide on Incentives for Responsible Investment in Agriculture and Food Systems Rating: 0 out of 5 stars0 ratingsTech to Table: 25 Innovators Reimagining Food Rating: 0 out of 5 stars0 ratingsOrganic, Inc.: Natural Foods and How They Grew Rating: 3 out of 5 stars3/5The Farm Bill: A Citizen's Guide Rating: 5 out of 5 stars5/5Food 5.0: How We Feed the Future Rating: 5 out of 5 stars5/5Designing Regenerative Food Systems: And Why We Need Them Now Rating: 0 out of 5 stars0 ratingsA Farmer's Guide to Climate Disruption Rating: 0 out of 5 stars0 ratings
Industries For You
YouTube Secrets: The Ultimate Guide to Growing Your Following and Making Money as a Video I Rating: 5 out of 5 stars5/5Unreasonable Hospitality: The Remarkable Power of Giving People More Than They Expect Rating: 4 out of 5 stars4/5INSPIRED: How to Create Tech Products Customers Love Rating: 5 out of 5 stars5/5All the Beauty in the World: The Metropolitan Museum of Art and Me Rating: 4 out of 5 stars4/5Weird Things Customers Say in Bookstores Rating: 5 out of 5 stars5/5All You Need to Know About the Music Business: Eleventh Edition Rating: 0 out of 5 stars0 ratingsUncanny Valley: A Memoir Rating: 4 out of 5 stars4/5Artpreneur: The Step-by-Step Guide to Making a Sustainable Living From Your Creativity Rating: 3 out of 5 stars3/5Comedy Fillers: 200 Quips & One-Liners Rating: 0 out of 5 stars0 ratingsA Study of the Federal Reserve and its Secrets Rating: 4 out of 5 stars4/5How We Do Harm: A Doctor Breaks Ranks About Being Sick in America Rating: 4 out of 5 stars4/5Summary and Analysis of The Case Against Sugar: Based on the Book by Gary Taubes Rating: 5 out of 5 stars5/5Not All Diamonds and Rosé: The Inside Story of The Real Housewives from the People Who Lived It Rating: 4 out of 5 stars4/5CDL - Commercial Driver's License Exam, 2024-2025: Complete Prep for the Truck & Bus Driver's License Exams Rating: 3 out of 5 stars3/5Excellence Wins: A No-Nonsense Guide to Becoming the Best in a World of Compromise Rating: 5 out of 5 stars5/5Waiter Rant: Thanks for the Tip—Confessions of a Cynical Waiter Rating: 3 out of 5 stars3/5Bottle of Lies: The Inside Story of the Generic Drug Boom Rating: 4 out of 5 stars4/5Setting the Table: The Transforming Power of Hospitality in Business Rating: 4 out of 5 stars4/5Music Law: How to Run Your Band's Business Rating: 5 out of 5 stars5/5Sweet Success: A Simple Recipe to Turn your Passion into Profit Rating: 5 out of 5 stars5/5Co-Intelligence: Living and Working with AI Rating: 4 out of 5 stars4/5Summary and Analysis of The Omnivore's Dilemma: A Natural History of Four Meals 1: Based on the Book by Michael Pollan Rating: 0 out of 5 stars0 ratingsSCOOPS: NOW A MAJOR MOVIE ON NETFLIX Rating: 4 out of 5 stars4/5Becoming Trader Joe: How I Did Business My Way and Still Beat the Big Guys Rating: 5 out of 5 stars5/5The Illusion of Choice: 16½ psychological biases that influence what we buy Rating: 3 out of 5 stars3/5The Reckoning Rating: 4 out of 5 stars4/5
Reviews for How to Feed the World
0 ratings0 reviews
Book preview
How to Feed the World - Jessica Eise
About Island Press
Since 1984, the nonprofit organization Island Press has been stimulating, shaping, and communicating ideas that are essential for solving environmental problems worldwide. With more than 1,000 titles in print and some 30 new releases each year, we are the nation’s leading publisher on environmental issues. We identify innovative thinkers and emerging trends in the environmental field. We work with world-renowned experts and authors to develop cross-disciplinary solutions to environmental challenges.
Island Press designs and executes educational campaigns in conjunction with our authors to communicate their critical messages in print, in person, and online using the latest technologies, innovative programs, and the media. Our goal is to reach targeted audiences—scientists, policymakers, environmental advocates, urban planners, the media, and concerned citizens—with information that can be used to create the framework for long-term ecological health and human well-being.
Island Press gratefully acknowledges major support of our work by The Agua Fund, The Andrew W. Mellon Foundation, The Bobolink Foundation, The Curtis and Edith Munson Foundation, Forrest C. and Frances H. Lattner Foundation, The JPB Foundation, The Kresge Foundation, The Oram Foundation, Inc., The Overbrook Foundation, The S.D. Bechtel, Jr. Foundation, The Summit Charitable Foundation, Inc., and many other generous supporters.
The opinions expressed in this book are those of the author(s) and do not necessarily reflect the views of our supporters.
Island Press’ mission is to provide the best ideas and information to those seeking to understand and protect the environment and create solutions to its complex problems. Click here to get our newsletter for the latest news on authors, events, and free book giveaways. Get our app for Android and iOS.
Book Title of How to Feed the WorldCopyright © 2018 Jessica Eise and Ken Foster
All rights reserved under International and Pan-American Copyright Conventions. No part of this book may be reproduced in any form or by any means without permission in writing from the publisher: Island Press, 2000 M Street NW, Suite 650, Washington, DC 20036.
ISLAND PRESS is a trademark of the Center for Resource Economics.
Library of Congress Control Number: 2017950979
All Island Press books are printed on environmentally responsible materials.
Manufactured in the United States of America
10 9 8 7 6 5 4 3 2 1
Keywords: agriculture, crops, farming, fertilizers, food waste, international trade, irrigation, pesticides, soil, sustainability
CONTENTS
Introduction
Jessica Eise and Ken Foster
Chapter 1 Inhabitants of Earth
Brigitte S. Waldorf
Chapter 2 The Green, Blue, and Gray Water Rainbow
Laura C. Bowling and Keith A. Cherkauer
Chapter 3 The Land That Shapes and Sustains Us
Otto Doering and Ann Sorensen
Chapter 4. Our Changing Climate
Jeff Dukes and Thomas W. Hertel
Chapter 5 The Technology Ticket
Uris Baldos
Chapter 6 Systems
Michael Gunderson, Ariana Torres, Michael Boehlje, and Rhonda Phillips
Chapter 7 Tangled Trade
Thomas W. Hertel
Chapter 8 Spoiled, Rotten, and Left Behind
Ken Foster
Chapter 9 Tipping the Scales on Health
Steven Y. Wu
Chapter 10 Social License to Operate
Nicole J. Olynk Widmar
Chapter 11 The Information Hinge
Jessica Eise
Chapter 12 Achieving Equal Access
Gerald Shively
Conclusion
Jessica Eise and Ken Foster
Afterword
Acknowledgments
Notes
Contributors
Index
Introduction
Jessica Eise and Ken Foster
In the chilly Indiana winter of early 2016, we sat down for a meeting. We were in the agricultural economics building at Purdue, which has served as Indiana’s land grant university since 1869, where we work with some of the world’s foremost experts on food, health, and the environment. All those present at this meeting, in their individual research, were seeking answers to the enormous challenge of feeding the world sustainably.
Our meeting was an unusual one. We were seeking to determine how we could bring our core expertise together in a way that was accessible for people outside the walls of academia. We wanted people far beyond the labs, classrooms, and fields of Purdue to see how issues as varied as irrigation, tariffs, soil health, and diet decisions interconnect. In doing so, we hoped to highlight the critical challenges we must overcome to feed the world, all the while showing that a healthy, plentiful food system is possible when we take an integrated approach.
From that meeting, the idea of this book was born. Our first step, we realized, was identifying the challenges themselves. With so many factors affecting our food system, what issues were primary? Months passed after that initial meeting as we bounced ideas back and forth, consulted with colleagues, sat in on lectures, read, researched, and argued. In the end, we agreed on 12 topics:
Population growth
Water scarcity
Land use
Climate change
Technology adoption
Competing food systems
International trade
Food waste and loss
Health
Social license to operate
Communication
Achieving equal access to food
By the time we nailed these down, winter was long gone. It had then become a matter of getting the right researchers onboard. More digging, meetings, conversations, and emails ensued, from which an extraordinary team was born. To name just a few, from the Purdue Center for Climate Change Research, Jeff Dukes, who holds the Belcher Chair for Environmental Sustainability, came aboard. In the Agronomy Department, hydrologist Laura Bowling joined the team. In Agricultural and Biological Engineering, Keith Cherkauer, an environmental engineer, agreed to participate. From Horticulture, we found Ariana Torres. And within our own department, Agricultural Economics, there was a wealth of expertise, such as development expert Gerald Shively and population guru Brigitte Waldorf, and, within the Center for Global Trade Analysis, both Tom Hertel and Uris Baldos decided to contribute.
One by one, we built the team until we reached a total of 17 participants. Together, we had managed to form a group comprising some of the most cutting-edge researchers in the field of food and agriculture. The group, in terms of both expertise and personal backgrounds, is tremendously diverse. Ranging from Germany, the Philippines, and Ecuador to the United States and beyond, their origins and life experiences shaped their interests in the subject matter they address. In many cases, they weave their own personal experiences into their chapters, connecting the big issues to our tangible, day-to-day existence. With knowledge spanning concepts as tiny as the water molecule to as great as Earth’s atmosphere, our collective range of expertise grew to be as vast as the planet itself.
Holding together a group of 17 scientists and researchers, while they all juggle so many competing demands for their time, proved to be an undertaking in itself. A stubborn focus on the end goal was the glue that held everyone together the following year of writing, deadlines, and rounds of revisions. That end goal was more than just a book. It was the goal of sharing information beyond the confines of the Ivory Tower, motivated by a belief in the importance of knowledge that is accessible for everyone. We live in a society today where the boundaries between fact, fiction, and opinion are easily blurred, yet food security is far too tenuous, and far too important, to depend on shadowy misconceptions.
This book is an objective resource on what we really face in food and agriculture. It lays out our greatest challenges in a clear, straightforward way that is available for those who are interested. The issues herein are straight from the mouths of scientists and researchers. We didn’t pay anyone to contribute to this book. Nobody’s research was funded as a result. Every contributor played a part because collectively they understand that our future depends on our ability to work together empowered by knowledge—and that members of our society deserve a trusted resource. With little incentive to participate, their contributions to this daunting task demonstrate how much they care about helping us, as a society, come to grips with the challenges described in this book.
In these times of growing challenges, the difference between working with or against one another can be the difference between food abundance or shortage, environmental preservation or destruction, and even life or death. Politicians must be empowered to make wise decisions. We, the consumers of food, need knowledge so we can wield our influence and purchase power wisely. Farmers should thrive with the best information and practices possible. Funds must flow to wisely chosen research projects that fit into the larger needs of society.
Many scenarios are possible for the future of our food, our world, and its people. Some are disturbing, but others are quite encouraging. Where we end up hinges mightily upon how we address the challenges outlined in the following pages. We can spiral into conflict, failing to nourish the people of our world, spawning illness, suffering, death, and injustice. Or we can thrive together as a global community, ensuring that all human beings have access to sound nutrition for themselves and their children. We sincerely hope that this book leads us, as a society, closer to a conversation focused on facts and shared values that will carry us nearer to this goal.
Chapter 1
Inhabitants of Earth
Brigitte S. Waldorf
The world’s growing population is more than a matter of numbers.
How many children do you wish to have?
This is the first question I ask in my classes on population. Hundreds of students have answered this over my many years of teaching. The vast majority of responses range between zero and two.
But there is almost always one student in class—without exception it has been, thus far, a male student—who wants to have many kids. His answer of five or six
inevitably triggers a very interesting conversation on the pros and cons of large family sizes. The expense of raising a child is typically their main reason against many kids. In the United States, these costs are estimated¹ to range between $12,350 and $13,900 per year for a child living in a middle-income, two-child, married-couple family, and this does not include the social investments made in children for things like public health and education.
After this, our class conversation generally turns to awareness of and access to birth control, contraceptive failure, and unintended pregnancies. At last, we branch out to the question of how our own individual fertility decisions will impact the world’s population growth. It is this, our growing, global population, which is the great matter of concern. Yet few of us think about how our tiny, personal fertility decisions (which don’t feel tiny to us at all, coincidentally) contribute to the giant, increasing ticker that measures the quantity of people living on our planet. What even fewer of us think about is that the matter of population is not nearly so simple as how many kids we have or plan on having. There are important follow-up questions we must answer, such as, Where do you plan on living? How old are you going to get? How long can your children expect to live?
It comes as a surprise to many that our personal life choices—beyond how many offspring we wish to have—influence population. Not smoking, eating a healthy diet, exercising regularly, and following all the doctors’ advice influence our lifespan. Those extra years we add to our time on Earth will, ultimately, also impact how large the world population is and how fast it will grow.
As I explain to my classes, these choices and decisions, such as eating well or going to the doctor, arise from a place of privilege wrought from a certain socioeconomic status. To decide how many children to have, and how to live, demands a degree of education and economic power. Yet not everyone shares similar privileges. Not everyone can choose. It sounds paradoxical but, as we’ll see, not having a choice can have an even greater, and sometimes undesirable, impact on the world’s population growth.
One area in which this manifests quite keenly is women’s reproduction. The United Nations reports that in certain African countries the availability of contraceptives (such as condoms and other means of birth control) is very low. There is a huge, unmet need for family planning.² Without contraceptives, having kids just happens.
It is not a surprise that these countries also have the highest fertility rates (or number of births in a woman’s lifetime) in the world.
Another space in which we see this is death. With respect to mortality, the desire to live longer is certainly universal. But in many parts of the world, people don’t have the luxury to contemplate their health, lifestyles, environmental quality, and long-term well-being. The urgent need to simply survive in the here and now overshadows these concerns. Filling an empty stomach in that exact moment is what counts, especially when you can’t be sure of the next opportunity to do so.
Whether wrought by choice or circumstance, these individual behaviors are embedded in a broader context. This broader context is shaped by many factors, such as the environment, economy, and policies. The chapters in this book delve into these issues, and, as you sift through the pages, you can well imagine how some of these challenges influence population levels. Environmental factors such as desertification and soil degradation reduce the amount of food farmers can grow on their land, which in turn diminishes the population that can be sustained. Even more extreme is the complete loss of arable land along the coasts and rivers as a result of climate change–induced sea level rise.
With the broader context taken into consideration, population experts agree we will likely hit about 10 billion people by the year 2050. Yet what does that number even mean? Can we achieve global food security and improve nutrition with so many people on Earth? How can we do so? When will we be able to do so, and what limits humankind’s ability to achieve global food security?
Concern about our ability to provide sufficient food for the planet’s growing population is at the center of the population debate. The food–population nexus is full of intricate nuances. Issues vary across countries and people. And the complexities only increase as population numbers are subjected to, and contribute to, an uncertain future in a world of elaborate political threads, environmental problems, and climate change. Planning for a future in this complex, multifaceted web of population, food, environment, and climate is a monumental task. The manner in which we confront the uncertainties surrounding future population change underpins the entire food debate.
On the Rise
The world population has been, for the most part, growing ever since the first agricultural revolution about 10,000 years ago. This was when humans began to transition from hunting and gathering to settled agriculture. Growth was slow and steady for the next eight millennia, but for a few calamitous interruptions along the way. The most well known of these is the Great Plague in Eurasia in the fourteenth century. As disease swept the continent, a shocking portion of the population died, with estimates running from 20 to 50 percent and higher in some areas.
But aside from these few exceptions, caused by epidemics such as the Great Plague or prolonged wars, the population growth was very slow and barely noticeable. There were but a few million people at the beginning of the first agricultural revolution. From that point, it took approximately 8,000 years for numbers to grow and hit one billion in 1800. Yet once that first billion was hit, growth skyrocketed. Adding the second billion took 130 years: by 1930, we had doubled our population in less than 2 percent of the time it had taken us to get from the first agricultural revolution to one billion.
Then, in less than a hundred years, we jumped from two to nearly eight billion people (fig. 1.1). As the graph shows, the time needed to reach each consecutive billion became shorter and shorter, plateauing somewhat over the past 50 years. Without giving too much away, since I was born, our population has grown by literally billions. The same can be said for you! Today, 7.6 billion people share our planet. And just this year alone, we will welcome 83 million. That is far more than twice the entire Canadian population alone. The additional 83 million people per year need shelter, health care, education, jobs, transportation, clean air, and clean water. And, of course, food.
It is expected that the threshold of 8 billion will be reached just a few short years from now, at the end of 2022. While I mentioned earlier that experts predict 10 billion by 2050, that is still a rough estimate. Why? It is not simple to predict population growth. Any statement about how the population size will change in the future is filled with uncertainty. These estimates require us to make assumptions about future demographic behaviors and patterns. That is, we need to sketch out scenarios to describe how we will behave.
Figure 1.1. From one to eight billion in 225 years.
The United Nations has made projections under different scenarios.³ First, imagine a scenario where both fertility and life expectancy remain as they were during the recent past. This is the United Nations’ no-change scenario.
It is a benchmark for comparison. The result is an astounding 19.7 billion inhabitants on Earth by 2100. This is an additional 12 billion people, or more than two and a half times as many people as currently inhabit Earth. Once we delve into the specifics of providing housing and food for an additional 12 billion people in just 80 years, it becomes quite clear that this scenario would make the twenty-first century extraordinary, to say the least.
Yet we likely won’t face such a scenario. Assuming no change
in demographic patterns would be entirely counter to what has played out in the past centuries. The past 300 years have shown us how drastically demographic patterns can change, and how differently they play out in different places.
To better understand this, let’s look at England. England was the first country to go through the demographic transition from high mortality and high fertility to low mortality and low fertility. Simply put, they were the first population to shift from dying young and having a lot of babies, to living a long time and not having that many babies.
After the onset of industrialization, England’s mortality dropped in large part due to the major decline in deaths from infectious diseases, such as cholera, smallpox, and typhus. Improved sanitation, medical advances, and an improved food supply contributed to this decline. Because of these improvements, the population grew quite rapidly at first. In fact, it more than doubled in the early half of the 1800s.
Yet this trend was short-lived. Toward the end of the 1800s, fertility rates began to decline sharply. In 1871, English women had, on average, 5.5 babies each. Fifty years later, they had an average of only 2.4 babies.⁴ This decline happened even before the emergence of modern contraceptives, such as the birth control pill in the 1960s.
To better grasp this, imagine the following scenario. Mary, a British homemaker in 1867, is 33 years old and has seven children all under the age of 16. Her neighbors’ families are all, more or less, the same size too. She, her husband Frank, and their children all benefit from the better sanitation, medical treatments, and food supply wrought by industrialization. As the years roll past, something happens that in earlier years was nearly unheard of—only one of Mary’s seven children dies during childhood. Mary’s children soon grow up and have children of their own. Fast forward to the roaring 1920s. Mary is still alive, now an old woman, and is surprised that her children and grandchildren have kept their families so small. Not one of her progeny has more than four children, and some don’t even have any at all!
Mary lived through what we now understand to be a common demographic shift for high-income countries. Today, England has long since completed this transition. Life expectancy is very high, at 81 years, and fertility is quite low, at 1.9 babies per woman. This is even below the replacement level of 2.1 babies, the number of children needed to keep a population stable.
All high-income countries⁵ over the past century and a half have followed this very same trend at slightly different times. It is a transition into what we call a low mortality/low fertility regime.
In some countries today, the declines are even more drastic than what we see in England. Take Japan, for instance. The Japanese can expect to live two years longer than the British, and Japanese women have an average of only 1.4 babies.
To many, this initially feels counterintuitive. As the standard of living rises, and there is a lower chance of mortality, we technically have more money to raise kids and we don’t have to deal so frequently with the horrors of dying young, or watching children die young. Nonetheless, we have fewer kids. And middle-income countries are well on their way to following this same trend. World Bank data⁶ suggest that life expectancy in Mexico climbed from 57 years in 1960 to 77 years in 2014. Due to successful government-sponsored family planning programs, during that same time period Mexican fertility dropped from 6.8 to 2.2 babies born per woman.
Similar developments are being observed in lower-middle income countries. In Myanmar, for example, life expectancy increased from 43 to 66 years between 1960 and 2014, whereas the number of babies born decreased from 6.1 to 2.2 per woman. In low-income countries, life expectancy has already increased whereas fertility is only starting to decline. In Mozambique, for instance, people now live 55 years on average, up from 35 years in 1960. Yet the number of babies born per woman only slightly dropped so far, from 6.6 babies to 5.4.
These changes are the reason why the no-change scenario
and its prospect of 19.7 billion people in 2100 is such an unrealistic outcome. It is far more realistic to think about scenarios that allow for declines in both mortality and fertility, especially the latter. The issue is, what are reasonable assumptions about the speed of the mortality decline? And what is a good estimate for the speed of fertility decline in the middle and low income countries?
Given these complexities, in addition to the no-change scenario, the United Nations also projects other scenarios for the world’s future population that take into account varying degrees of declining mortality and fertility. The chart here shows three of these projections (fig. 1.2). Each makes different assumptions about the fertility decline. They are labeled as low, medium, and high (as well as the no change projection). The projections start in 2015 and extend to the end of the century. As you can see, differences among them emerge quite early. After just 20 years, the projections for high fertility and low fertility already differ by almost one billion people.
In the low-fertility scenario, one in which population experts track what they guess will be the lowest probable rates of fertility and mortality, the population never even reaches nine billion. In fact, it already starts declining by 2053. It further projects that by 2100 the population will be even smaller than it is today.
Yet in the high-fertility scenario, where researchers assume the higher end of probable fertility and mortality, the projected population figures exceed those of the no-change scenario for the first 62 years before dipping down below and reaching 16.5 billion in 2100. The medium-fertility scenario, the most commonly cited scenario, projects 9 billion people at the end of 2036, 10 billion at the end of 2054, and 11 billion in 2088. It is not as extreme as the high-fertility and no-change projections. This medium scenario also predicts that population growth will slow substantially as we reach the end of the century. In fact, its growth rate during the last year of the twenty-first century is close to zero (0.09 percent), hinting that population growth will level off in the twenty-second century, or even come to a total standstill.
A note of caution, however. The thing that