Imagine you’re a woman living in Pakistan who would like to decide if and when to have children. You’re going to school, or you’ve got a job, or you’ve had a child and simply want some space before your next pregnancy. How easy will it be for you to get your needs met?

Last year a Kiribati man, Ioane Teitiota, claimed asylum in New Zealand, stating that his home island, which is on average just two meters above sea level, was becoming uninhabitable thanks to rising seas. So-called “king tides” routinely wash over entire portions of the archipelago.

The original version of this article, by Kaja Jurczynska, appeared on Population Action International’s All Access blog.

Pakistan is at a crossroads, and not for the reasons you might think.

This past December, Bangladesh turned 42, bringing the country Henry Kissinger once predicted would become a “basket case” into comfortable middle age (though perhaps this analogy breaks down for countries like Switzerland, age 722).

Pakistan, long a nation defined by its large rural populations and dominant agricultural industries, is undergoing a dramatic urban shift.

According to UN Population Division estimates, the country is urbanizing at a three percent annual rate – the fastest pace in South Asia. In barely 10 years, nearly 50 percent of Pakistan’s 180 million people will live in cities (a third do today). Pakistani government projections using density-based rather than administrative definitions of urbanization suggest that Pakistan’s urban population has already reached 50 percent.

Today approximately 44 percent of the world’s 7.2 billion people are under 24 years old – and 26 percent are under 14. Of those 7.2 billion people, a staggering 82 percent live in less developed regions of the world – primarily sub-Saharan Africa and Asia. Currently, the global median age is 29.2 years old, a sharp contrast to Europe, for example, where the median age is 41.

The disastrous flooding in the Himalayan state of Uttarakhand this summer, which claimed more than 6,000 lives, was the outcome of a changing climate and poorly planned development. It was also another case in point of the increasing importance of environmental security in India – especially for the military.