With climate change already close to an irreversible tipping point, urgent action is needed to reduce not only our mean (carbon) footprints but also the "number of feet" - that is, the growing population either already creating large footprints or aspiring to do so, argues a leading physician and environmentalist in The BMJ today.

Yet John Guillebaud, Emeritus Professor of Family Planning and Reproductive Health at University College London, says most climate change discussions focus only on technology and consumption.

He points out that 45% of the world lives in areas where total fertility rates range from 2.1 to 5, and 9% where they exceed 5. In the 48 countries designated by the United Nations as least developed, population is projected to triple by 2100.

The UN's latest median world population projection of 11.2 billion by 2100 is predicated on continuing reductions in fertility rate, he adds. Without them, the constant fertility variant projects to roughly 28 billion by 2100.

Studies invariably show that family planning is highly cost effective compared with other emission abatement strategies, he explains.

For instance, simply by having one less child, an American woman would reduce her "carbon legacy" (the summed emissions of herself and her descendants weighted by relatedness) by 9441 tonnes, he writes. This is around 20-fold (10-fold in the United Kingdom) more than would be saved by other eco-actions.

He calls on health professionals to "advocate for voluntary family planning" and says "action on population growth as well as technology and consumption is essential to ensure that climate mayhem is both minimised and mitigated."

On Sunday, 5th June, Professor Guillebaud will be involved in celebrations for the ecotimecapsule project. Initiated in 1994 at botanic gardens in Kew and Ness, the Seychelles, New South Wales, Mexico and South Africa, it aims to make a decent, truly sustainable future a reality for our grandchildren - and for all the wild species in Nature that humankind so threatens. http://www. ecotimecapsule. com

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Note to Editors

Analysis: Voluntary family planning to minimise and mitigate climate change

Journal: The BMJ

Link to full article: http://press. psprings. co. uk/ bmj/ may/ familyplanning. pdf

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