Today is the first “International Day of the Girl Child” – a day established last year by the United Nations to acknowledge the rights and unique challenges faced by young girls around the world.

The latest UN projections put the number of women under the age of 19 at about 1.18 billion today. Especially in developing countries (though not only) these young girls often face outsized barriers to happy, healthy, and productive lives.

On April 1, 2012, a Chinese woman on her way to work suddenly felt the earth beneath her crumble and, in an instant, found herself plunging into an abyss of scalding hot water. The woman had unknowingly stepped into one of the many sinkholes appearing in China’s megacities. The emergence of sinkholes in China is part of a larger set of environmental issues related to rapid urbanization taking place in the Asia-Pacific region overall. [Video Below]

Eight years from now, the Gaza Strip will have “virtually no reliable access to sources of safe drinking water, standards of healthcare and education will have continued to decline, and the vision of affordable and reliable electricity for all will have become a distant memory for most,” according to a United Nations report released last month. The bleak assessment concludes that without immediate action to address immense and interconnected economic, demographic, environmental, infrastructure, and social challenges facing Gazans, “the already high number of poor, marginalized and food-insecure people depending on assistance will not have changed, and in all likelihood will have increased.”

This summer, 26 countries and private donors met at the London Summit on Family Planning to pledge $2.6 billion to expand family planning services to 120 million more women in the poorest countries around the world. But while the summit renewed focus on reproductive health with its ambitious target, “we’re now at that point where we have to really sit down and work through” how to achieve that goal, said Julia Bunting of the UK’s Department for International Development at the Wilson Center on September 17. [Video Below]

Earlier this month, there was a flurry of stories about brutal mass killings in clashes between the Pokomo and Orma communities over water and land in southeast Kenya’s Tana River County. The Kenyan media reported that about 30 people, including eight security personnel, had been killed and scores wounded, and reports on the death toll since last month are more than 100.

Following the steady economic growth that many African countries have experienced in recent years and continued population growth, urbanization has accelerated rapidly on the continent as people turn to cities to take advantage of new economic opportunities. But growing cities have led to another problem. According to a new Food and Agriculture Organization (FAO) report, Growing Greener Cities in Africa, urban populations are exceeding the capacity of African cities to provide food for them, putting nearly 300 million people at risk of hunger and malnutrition, and greener strategies – urban agriculture and better water use – could help considerably.

The United Nations biannual population projections are some of the most (if not the most) widely used numbers in demography. Researchers and policymakers alike rely on the figures to plan for present and future challenges. But few consider the story behind the statistics. Where does the data come from? The United Nations Population Fund (UNFPA) recently released a short documentary on conducting censuses in challenging environments, with a spotlight on Indonesia, Chad, the Palestinian Territories, Belarus, and Bolivia.

Twenty-five years have passed since the Brundtland Commission first brought sustainable development to international prominence. Today, the United Nations appears on track to replace the soon-to-expire Millennium Development Goals with “Sustainable Development Goals,” marking the extent to which the international community has embraced the concept. And yet, in spite of its prominence, a specific and measureable definition of sustainability remains lacking.