As the Earth’s population reached the six billion mark this week, Fred Meyerson, director of the Global Change Policy Project at the Yale Centre for Environmental Law and Policy said that “the two most important environmental challenges in the next century are likely to be climate change and the loss of biodiversity. Population growth drives both of these ecological crises, and the day of six billion is a reminder that there is much work left to do to achieve population stabilisation.”

Global population is still growing at 78 million per year and hundreds of millions of people still do not have access to safe and reliable reproductive health services and the means to choose the number and spacing of their children, according to Meyerson. He adds that many also lack safe drinking water, a reliable food supply and access to primary education.

“On a global scale, we have the means to change the trajectory of population growth while improving life for all of us, but we lack political will,” said Meyerson.

It is estimated that every 20 minutes the world gains almost 3,000 people but loses one more plant or animal species. “As we welcome the six billionth baby, we need to also assure that he or she – and the billions who come after – grow up in a world worth living in,” Meyerson said.

Meyerson was a contributor to the United Nations Population Fund (UNFPA) annual report, ‘The State of World Population 1999’, which was released in late September.

The UN report links population growth and climate change. “Global warming is a wild card inextricably linked to population-related issues, including fuel consumption, land use trade-offs and the potential limits on food and water supplies,” according to the report.

The title of the new UN report – Six billion: A Time for Choices – is appropriate, says Meyerson. In particular, he believes, the United States and other developed countries should make the choice to reassert a leadership role in both international family planning assistance and environmental protection without further delay.

“The increased awareness that environmental concerns are moving into the international arena will require that US environmental policy be more in concert with other nations, thus giving birth to a new field of environmental diplomacy,” said James Gustave Speth, dean of the Yale School of Forestry and Environmental Studies, and former head of the United Nations Development Programme.

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