Image: The UN projects that world population will peak at roughly three times the 3.5 billion people that inhabited the planet in 1968, the year Paul Ehrlich published The Population Bomb.
In 1968, Paul Ehrlich published The Population Bomb, a wildly-influential book that planted the issue of over-population so firmly in our brains that it takes effort to readjust to the fact that many people now fear depopulation more than overpopulation.
Pundits have used the 2026 death of Dr. Ehrlich as an opportunity to ridicule his predictions about the catastrophic impacts of exponential population growth. Ehrlich was massively wrong about human death tolls and his more draconian strategies for engineering birthrates are rejected by respected population experts including those at the United Nations Population Fund. But that does not mean, as columnist Jonah Goldberg asserts in the title of his opinion piece, that “Paul Ehrlich was wrong about everything.”
Large portions of The Population Bomb warn about with impacts of population growth on ecosystems, including those that support humanity. Specifically, Ehrlich predicted that human population would exacerbate desertification, water shortages, deforestation, soil deterioration, pesticide contamination, loss of biodiversity, and climate change. On these outcomes, Ehrlich was right.
Desertification – Ehrlich understood that the need to feed billions more people would exert pressure to use intensive grazing and industrial agriculture practices that exhaust soil, deplete water resources, and ultimately create deserts. A 2017 report by the Intergovernmental Panel on Climate Change (IPCC) found: “The range and intensity of desertification have increased in some dryland areas over the past several decades (high confidence)” (IPCC 2017, p 251). The IPCC also anticipates increases in desertification in the future resulting in reduced agricultural productivity, loss of biodiversity, reduced capacity for soil to sequester carbon, increased climate change impact, and growing risk of unhealthful dust storms.
The 2017 IPCC report emphasizes that desertification is driven by many causes, including population and income growth as reflected in this quote: “The main drivers of desertification interacting with climate change are expansion of croplands, unsustainable land management practices and increased pressure on land from population and income growth” (IPCC 2017, p 251).
Water Shortages – Related to desertification, Ehrlich warned that water supplies would be strained by population-driven demand for more food as well as water needed for domestic and industrial use. In 2026, the United Nations University published Global Water Bankruptcy: Living Beyond Our Hydrological Means in the Post-Crisis Era. This publication reports that many aquifers and water bodies have been so overdrawn that they may never make a full recovery. Since the early 1990s, over half of the planet’s large lakes have lost water. Roughly one-quarter of the world’s population depends on these lakes. Wetlands are disappearing, aquifers are shrinking, land is subsiding, agricultural zones are experiencing severe water stress, saltwater is infiltrating groundwater, and governments promise more water supply than they can realistically deliver. The situation has become so dire that this report uses the term “bankruptcy” to emphasize that mankind has blown past a “water crisis” and entered an era of permanent groundwater and ecosystem degradation. To quote this report: “Population growth, urbanization, and economic expansion have increased water demand to agriculture, industry, energy and cities” (Madani p 20).
Deforestation – The Population Bomb predicted that population growth and its related increase in food demand would worsen the clearing of forests and their ability to provide multiple benefits including watershed management, biodiversity, and carbon sequestration.
According to the Global Forest Resources Assessment 2025 by the Food and Agricultural Organization of the United Nations (FAO), the pace of deforestation has slowed and afforestation (the creation of new forests on land previously used for agricultural or grazing) now offsets much of the deforestation. Nevertheless, 489 million hectares of forest has been lost worldwide through deforestation since 1990 and forests still lose 10.9 million hectares globally each year. FAO attributes 90 percent of global deforestation to the expansion of agricultural uses.
Soil Degradation – Ehrlich warned that population growth would give permission for humans to double down on the plundering of soil in order to keep pace with demand. As seen in this quote from The Population Bomb: “I predict that the rate of soil deterioration will accelerate as the food crisis intensifies. Ecology will be ignored more and more as things get tough” (Ehrlich, p 49.).
According to a 2025 study: “Our current agricultural management approaches are causing ongoing soil degradation, manifested as the loss of soil organic matter, acidification, over-application of fertilizers, erosion, salinization, contamination, and biodiversity loss” (Kopittke p744). “Indeed, because of this central role in global existential challenges, soil security is itself now considered the eighth existential challenge facing humanity” (Kopittke p 745). “However, the global human population has increased rapidly over the last few centuries, and even more recently increasing from 2.5 billion in 1950 to 7.9 billion in 2021. This growth in human population has required a corresponding increase in food production – “ (FAO, 2024). “However, not only is the human population increasing, but consumption per capita is also increasing and dietary consumption patterns are changing (particularly the increasing consumption of meat), with these various factors causing the ongoing intensification of agricultural production” (Kopittke p 746).
Pesticide Impacts – The pesticides used to feed the human population boom have had a devastating impact on the natural world. As this quote from The Population Bomb points out: “It is safe to assume that our use of synthetic pesticides, already massive, will increase. In spite of much publicity, the intimate relationship between pesticides on the one hand and environmental deterioration on the other is not often recognized. This relationship is well worth a close look” (Ehrlich p 49).
According to a 2022 report from the United Nations Environmental Program (UNEP), population growth has spawned massive use of pesticides, with devastating impacts on the environment as well as human health. Specifically, global sales of pesticides and fertilizers grow by over four percent annually and are currently valued at over $300 billion per year (USD). Roughly 385 million cases of pesticide poisonings occur annually, causing an estimated 11,000 deaths worldwide every year.
Pesticides impact bees, birds, aquatic organisms and biodiversity in general. According to the USEPA, pesticides widely used in the US adversely affect 1,445 species, the habitats pf 658 endangered animals and 80 percent of all endangered plants and animals (Blackledge 2024).
Loss of Biodiversity – In 1968, The Population Bomb observed that the need to serve a growing population was leading at that time to a loss of biodiversity, which is essential to ecosystem and human health.
Fast forward to 2026 and the World Wildlife Fund reports that species are going extinct at rates that are from 1,000 to 10,000 times higher than natural extinction rates, meaning rates that would be occurring without the existence of human beings. This event, known as the sixth mass extinction, is driven by human activity including the unsustainable consumption of natural resources.
These rates of extinction “… are high enough to threaten important ecological functions that support human life on Earth, such as a stable climate, predictable regional precipitation patterns, and productive farmland and fisheries” (World Wildlife Fund 2022).
Climate Change – In 1968, The Population Bomb warned that increased carbon dioxide emissions were perpetuating the greenhouse effect and causing what we now call climate change. Ehlich predicted that a few degrees of warming could create drastic problems in farming, melting ice caps, and sea level rise,
In 2023, the 6th Synthesis Report of the Intergovernmental Panel on Climate Change began with this statement: “Human activities, principally through emissions of greenhouse gases, have unequivocally caused global warming, with global surface temperature reaching 1.1°C above 1850-1900 in 2011-2020. Global greenhouse gas emissions have continued to increase, with unequal historical and ongoing contributions arising from unsustainable energy use, land use and land-use change, lifestyles and patterns of consumption and production across regions, between and within countries, and among individuals (high confidence)” (IPCC 2023, p 4).
“Widespread and rapid changes in the atmosphere, ocean, cryosphere and biosphere have occurred. Human-caused climate change is already affecting many weather and climate extremes in every region across the globe. This has led to widespread adverse impacts and related losses and damages to nature and people (high confidence). Vulnerable communities who have historically contributed the least to current climate change are disproportionately affected (high confidence)” (IPCC 2023 p6).
According to the IPCC, this human-generated climate change is driving sea level rise and exposing millions of people to food insecurity as predicted in The Population Bomb. In addition, climate change is reducing water security, producing lethal heat events, increasing disease, and causing displacement while damaging ecosystems, biodiversity, and fisheries.
In a rare tone of optimism, the 2023 IPCC report notes promising improvements in the cost effectiveness of solar and wind energy. Unfortunately, one year later, United States voters elected a president who calls climate change a hoax and uses taxpayer money to scuttle wind farms and divert funding to oil and gas facilities.
Helping women prevent unwanted pregnancies is a highly effective yet little mentioned climate action strategy. According to Project Drawdown, universal education and voluntary family planning is a highly-effective climate action strategy as well as being essential to equitable economic development and health outcomes. Specifically, Project Drawdown estimates that adoption of its Health and Education Solution would avoid almost 70 gigatons of greenhouse gasses by 2050.
The Depopulation Boon – Worldwide population grew from 3.5 in 1968, when The Population Bomb was published, to 8.2 billion today, a 2.3-fold increase in 57 years. This growth has had a huge impact on water, soil, biodiversity, climate change and many other aspects of the natural world on which we rely for our existence. With the right preparation, human beings as well as the planet can greatly benefit as our numbers peak in the coming decades. Dr. Ehrlich was wrong about many things. But he was not wrong about everything.
Notes
Blackledge, Steve. 2024. EPA report says pesticides endanger wildlife. Environment America. Accessed at EPA report says pesticides endanger wildlife.
Ehrlich, Paul and Anne. 1968. The Population Bomb. New York: Ballantine.
FAO. 2021. COP 26: Agricultural expansion drives almost 90 percent of global deforestation. Accessed at COP26: Agricultural expansion drives almost 90 percent of global deforestation.
FAO. 2025. Global Forest Resources Assessment 2025. Food and Agricultural Organization of the United Nations. Accessed at https://openknowledge.fao.org/items/090d2fbb-32a6-412b-a3b8-1ce5c5905df2.
Goldberg, Jonah. 2026. Paul Ehrlich was wrong about everything. Los Angeles Times. Accessed at Column: Paul Ehrlich was wrong about everything – Los Angeles Times.
IPCC (Intergovernmental Panel on Climate Change). 2017. Desertification. Chapter 3 of Special Report on Climate Change and Land. Accessed at Chapter 3 : Desertification — Special Report on Climate Change and Land SRCCL_Chapter_3.pdf.
IPCC (Intergovernmental Panel on Climate Change). 2023. Summary for Policymakers. In Climate Change 2023 Synthesis Report: Contribution of Working Groups I, II, and III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [Core Writing Team, H. Lee and J. Romero (eds.)] IPCC. Geneva, Switzerland, pp 1 -34, doi: 10.59327/IPCC/AR6-9789291691691647.001. Accessed at IPCC_AR6_SYR_SPM.pdf.
Kopittke, Peter, et. al. 2025. Soil degradation: An integrated model of causes and drivers. International Soil and Water Conservation Research. Accessed at Soil degradation: An integrated model of the causes and drivers – ScienceDirect.
Madani, K. 2026. Global Water Bankruptcy: Living Beyond Our Hydrological Means in the Post-Crisis Era. United Nations University Institute for Water, Environment, and Health. Accessed at Global_Water_Bankruptcy_Report__2026_.pdf.
Project Drawdown. 2022. How advancing health and education can reduce greenhouse gasses. Accessed at How advancing health & education can reduce greenhouse gases | Project Drawdown®.
UNEP (United Nations Environmental Program. 2022. Synthesis Report on the Environmental and Health Impacts of Pesticides and Fertilizers and Ways to Minimize Them. Accessed at pesticides.pdf.
World Wildlife Fund. 2026. What is the sixth mass extinction and what we can do about it? World Wildlife Fund. Accessed at The Sixth Mass Extinction | World Wildlife Fund.
