The Wilson Center Policy Briefs are a series of short analyses of critical global issues facing the next administration that will run until inauguration day.

Seven billion people now live on Earth, only a dozen years after the global population hit six billion. But this milestone is not about sheer numbers. Demographic trends will significantly affect the planet’s resources and people’s security.

It is well known that public health issues that affect the world’s most vulnerable populations – food insecurity, maternal and child health, water- and sanitation-related disease, and resource scarcity – are inextricably linked. Where these linkages are strongest, experience on the ground has shown that community-based integrated approaches to development provide more effective and sustainable solutions over vertical, sector-based programs. But so far, there are very few comprehensive evaluations providing strong quantitative evidence of this advantage.

The original version of this article, by Elisabeth Rosenthal, appeared in The New York Times.

In the tiny tortillerias of this city, people complain ceaselessly about the high price of corn. Just three years ago, one quetzal – about 15 cents – bought eight tortillas; today it buys only four. And eggs have tripled in price because chickens eat corn feed.

1.8 million food producers using improved technologies or management practices. Nearly 9 million children reached through nutrition programs. 2.4 million hectares under improved technologies or management practices. New mechanisms for donor coordination. A forward-looking agricultural research agenda. Innovative private-sector partnerships to support smallholder farmers. These are among the successes reported for the first three years of Feed the Future, the U.S. government’s new global hunger and food security initiative.

The CIA may have shut down its dedicated climate change center earlier this year, but a recently released report sponsored by the intelligence community reaffirms the deep connection between climate change and national security. New threats to U.S. national security – like increased food and water insecurity and more natural disasters requiring humanitarian assistance – have emerged as climate change creates unprecedented changes in the global environment.

“We are at a critical juncture in human history, which could lead to widely contrasting futures,” writes the chairman of the National Intelligence Council (NIC) Christopher Kojm in the council’s latest forward-looking quadrennial report, Global Trends 2030: Alternative Worlds, released yesterday.

This year, principal author Mathew Burrows and his colleagues focus on a series of plausible global scenarios for the next 20 years and the trends or disruptions that may influence which play out. Among the most important factors in these projections are demography and the environment.

Without decisive action, global temperatures could rise by at least four degrees Celsius (seven degrees Fahrenheit) by the end of the century. A new World Bank report says that such a world would be “so different from the current one” that it would be difficult to even anticipate the challenges we would face.

“There is as much of that water on the planet today as when the first amphibian flopped ashore; as much as when the ancient Greeks divined the future in the babble of brooks,” writes William Wheeler in The Christian Science Monitor. “So why do experts in science, economics, and development warn that a ‘global water crisis’ threatens the stability of nations and the health of billions?”