National Geographic Society Newsroom

David Richardson’s uncomfortable climate change solution

By Daniel Grossman in Copenhagen David Richardson, a lively, friendly man, devotes his life to a goal some people consider quixotic at best and possibly dangerous at worst: to reduce the number of humans on Earth by about two-thirds. Richardson’s views are long- and strongly-held. When only five he noticed that people with large families...

By Daniel Grossman in Copenhagen

David Richardson, a lively, friendly man, devotes his life to a goal some people consider quixotic at best and possibly dangerous at worst: to reduce the number of humans on Earth by about two-thirds. Richardson’s views are long- and strongly-held. When only five he noticed that people with large families on his home island of Jersey, England were poor. He concluded right then that extra people equal a poorer quality of life, he says. This insight, with much more nuance, drives him today, more than 50 years later. Before he married, Richardson asked his wife to sign a contract pledging to have no more than two children. At the Copenhagen Conference, where he represents the Optimum Population Trust, a British non-governmental organization, he proudly sports a large button that says “Stop Global Warming: Take the Pill.” His email includes the phrase “stop@2children.”

David Richardson.jpg
David Richardson. Photo by Daniel Grossman.

The Kaya Equation, a formula widely used for tallying humanity’s total carbon dioxide output, states the following:

CO2 Emissions = Population × (GDP/Population) × (Energy/GDP) × (CO2 /Energy)

The implications of this scientific formulation are clear: in order to reduce carbon dioxide output you must cut some mixture of population, wealth per person, energy per unit of wealth and the amount of carbon dioxide produced for each unit of energy. Population experts say that unless attitudes and practices change, the global population will reach about 9 billion people by 2050, exacting a heavy additional toll on Earth’s land and water and contributing significantly to the problem of reducing carbon dioxide production. However, suggestions for how to produce less carbon dioxide generally include any factor other than population, which is studiously avoided.

There are good reasons why smart people seem to overlook the obvious and decline to discuss population growth, one of the most fundamental reasons why cutting carbon dioxide emissions will be difficult. The topic raises ethical dilemmas touching on some of the most contentious social issues like birth control, abortion and the unequal distribution of wealth. Paul Ehrlich, author of The Population Bomb and the most renowned and persistent advocate of controlling the human population, is routinely lambasted as racist.

Eric Rimmer of the Optimum Population Trust discusses the difficulties of discussing population control

David Richardson launched the Optimum Population Trust in 1991–though he no longer serves in an official capacity. As an opening salvo in his campaign to control the number of people on Earth, he organized a debate in the British House of Commons that year with a title that concisely stated his concerns: “Given that overpopulation is one of the greatest threat to the environment, this House believes that the Government should implement legal, fiscal & social policies in order to ensure a steady reduction in the Population of the United Kingdom in the 21st century.”

Like Paul Erhlich–a board member of the trust–Richardson not only wants to slow population growth down: he’d like to cut it back, significantly. He says he’d like Britain to have just 20 million inhabitants, 40 million fewer than today, though he calls the goal “academic not realistic.” He speaks approvingly of another population control advocate who believes Earth should have 2 billion, not the present 6 billion, human inhabitants. The trust promotes making voluntary birth control more easily and widely available as one of the cheapest and fastest ways to cut carbon dioxide production. As one of the group’s publications attests, “a non-existent person has a zero carbon footprint.”

The trust has recruited some celebrity supporters, including, recently, the famous nature filmmaker David Attenborough. Still, Richardson realizes his ideas are unpopular and he admits that his goal will remain elusive.


Daniel Grossman has been a print journalist and radio and web producer for 20 years. He has reported from all seven continents including from within 800 miles of both the south and north poles. He has produced radio stories and documentaries on science and the environment for National Public Radio’s show Weekend Edition; Public Radio International’s show on the environment Living on Earth and news magazine, The World and many other international broadcasters. Among others, he has written for the New York Times, The Boston Globe, Discover, Audubon and Scientific American.

Corrections have been made to this post from its original published form.

About National Geographic Society

The National Geographic Society is a global nonprofit organization that uses the power of science, exploration, education and storytelling to illuminate and protect the wonder of our world. Since 1888, National Geographic has pushed the boundaries of exploration, investing in bold people and transformative ideas, providing more than 14,000 grants for work across all seven continents, reaching 3 million students each year through education offerings, and engaging audiences around the globe through signature experiences, stories and content. To learn more, visit or follow us on Instagram, Twitter and Facebook.

Meet the Author

Author Photo David Max Braun
More than forty years in U.S., UK, and South African media gives David Max Braun global perspective and experience across multiple storytelling platforms. His coverage of science, nature, politics, and technology has been published/broadcast by the BBC, CNN, NPR, AP, UPI, National Geographic, TechWeb, De Telegraaf, Travel World, and Argus South African Newspapers. He has published two books and won several journalism awards. In his 22-year career at National Geographic he was VP and editor in chief of National Geographic Digital Media, and the founding editor of the National Geographic Society blog, hosting a global discussion on issues resonating with the Society's mission and initiatives. He also directed the Society side of the Fulbright-National Geographic Digital Storytelling Fellowship, awarded to Americans seeking the opportunity to spend nine months abroad, engaging local communities and sharing stories from the field with a global audience. A regular expert on National Geographic Expeditions, David also lectures on storytelling for impact. He has 120,000 followers on social media: Facebook  Twitter  LinkedIn