As most of the world’s governments are puzzling out what they can offer to combat global climate change, a sensitive but critical aspect of the problem is coming into clearer focus: population. The word appears 20 times in a new 66-page synthesis of country pledges to cut greenhouse-gas emissions by the UN Framework Convention on Climate Change’s Secretariat. And those are the mentions of population in the context of size or growth, not the word’s more frequent use as a synonym for “people.”

The world has entered a new energy era. Last year, for the first time in four decades, the global economy grew without an increase in CO2 emissions, according to the Renewable Energy Policy Network for the 21^st Century.

China’s announcement of a nationwide cap-and-trade program is a sign that the government is serious in its “war against pollution,” says China Environment Forum Director Jennifer Turner, and it may help move the climate change discussion in the United States too.

The focus of the global community on the outcomes of the Paris Conference of Parties (COP) to the UN Framework Convention on Climate Change (UNFCCC) in December is unprecedented. The world awaits, anticipating the details of an international and legally-binding agreement to address climate change. [Video Below]

By comparing “first wave” developing countries, like Sweden and the United States, to “second wave” developers, like South Korea and Japan, Thomas Anderson and Hans-Peter Kohler of the University of Pennsylvania seek to explain why countries that underwent socioeconomic development in the first half of the 20th century have slightly higher fertility levels than those that developed later. Despite “both sets of countries attaining high income and generally low fertility, contemporary gender norms and levels of gender equity differ between them,” write Anderson and Kohler in a new study in Population and Development Review.

The announcement in Washington on September 24 that President Xi Jinping is committing China to a national carbon trading system is the latest step in an important partnership between the two biggest carbon emitters in the world.

As Pope Francis gets into high gear on his visit to the United States, it’s worth reviewing details and contexts in the extraordinary message to Catholics and the rest of the planet in “On Care for Our Common Home,” the encyclical he issued earlier this year.

As the world prepares for a pivotal climate conference in Paris this December, countries are offering their national plans to tackle a changing climate. These plans, known as intended nationally determined contributions (INDCs), contain details of what each country is prepared to do as part of a new global climate agreement. While the public focus is often on mitigation – how much countries are willing to reduce emissions, by when, and with what degree of transparency – adaptation to the impacts of climate change demands the same level of attention. In fact, the last round of international climate talks in Lima invited parties to include adaptation in their INDCs.