$1 billion sales in two minutes. More than 250,000 purchases every second. Singles’ Day, China’s annual retailing extravaganza, absolutely crushes Black Friday: E-commerce giant Alibaba raked in $17.8 billion in gross sales during last year’s event, more than double the combined total of $6.8 billion in sales during the United States’ 2016 holiday shopping kick-off. The shopping spree lasts only 24 hours, but its environmental impacts will extend for decades.

“In the end, we all have to be accountable,” said Geoff Healy of BHP Billiton, the largest natural resource extraction company in the world, at a recent event on transparency, anti-corruption, and sustainable development at the Brookings Institution.

To meet the climate challenge, city leaders are committing to ambitious emissions targets, designing decentralized action plans, and sharing lessons in transnational networks. Since growing cities are a large source of global emissions, their efforts could contribute substantially to global climate objectives. As the world’s climate experts gather next week in Bonn, Germany, for the 23rd Conference of the Parties (COP-23), urban initiatives will be a key focal point of the agenda-setting conversation.

Water is a “strategic instrument in the creation of a safer, healthier, more nutritious, less aggressive world,” said Winrock International President and CEO Rodney Ferguson at the first event in a four-part series on water security organized by the Wilson Center and the Sustainable Water Partnership. Panelists at the event identified innovative and integrated efforts necessary to increase global water security in the face of growing water scarcity.

Over the past 25 years, economic and political demographers have documented how declines in fertility rates have preceded improvements in state capacity, income, and political stability in much of East Asia, Latin America, and, most recently, in the Maghreb region of North Africa (Tunisia, Morocco, Algeria). Nonetheless, social scientists still debate over where and when this “demographic dividend” will occur in the youthful, low-income countries of sub-Saharan Africa.  Elizabeth Leahy Madsen of the Population Reference Bureau and I find that, for most youthful countries—like those in sub-Saharan Africa—changes in population age structure provide a means to gauge the timing of their future development.

As the climate changes, cities will suffer. “These are important places that have a lot of people, property, and local economies that are going to struggle,” said Jessica Grannis, the adaptation program manager at Georgetown’s Climate Center, at a recent Wilson Center event on the role of subnational decision-makers in achieving international goals.  “The good news is that, here in the United States, many cities are recognizing these threats to their people and populations, and they’re beginning to take action,” said Grannis.