“Climate work is practical, common-sense, good development,” said Carrie Thompson, deputy assistant administrator at the Bureau for Economic Growth, Education, and Environment at the U.S. Agency for International Development (USAID). “It’s prevention, and we all know that preventative medicine is the best medicine.”

AGADEZ, Niger — The world dismisses them as economic migrants. The law treats them as criminals who show up at a nation’s borders uninvited. Prayers alone protect them on the journey across the merciless Sahara.

As global climate change affects livelihoods across the world, migration patterns are also changing. In a recent study published in Global Environmental Change, Clark Gray, Valerie Mueller, and I found that since the 1970s, climatic variations have been increasing internal migration across many South American countries, with few exceptions. And many people are headed to cities.

“Before the famine my life was better. I was a man in my own country,” Abdi Abdullahi Hussein, a Somali refugee living in Kenya, tells The Climate Reality Project. “When you have livestock and a farm and it all disappears, it feels like falling off a cliff.”

Eddah Senetoi lives with her son in the small pastoralist community of Elangata Waus. They keep cows, goats, sheep, and donkeys to buy food and pay school fees. For her and other pastoralists living in southern Kenya’s Kajiado County, climate change is compounding challenges from land subdivision and privatization, and magnifying social tensions and community conflicts over access to resources.

It had been raining for two full days when the landslide came. Nirjala Adhikari vividly remembers the instant it hit her village in Sindhupalchok District, Nepal. “It was a very scary moment, and I couldn’t think of anything else than grabbing my mobile phone and my school certificate before I ran out of the house,” she recalled. “I secured my certificate because only this will help me establish a bright future.”

“Water is the frontline of climate change. It’s what every report that you see identifies as the sort of first and foremost effect we see from a climate changing world,” said Sherri Goodman, a public policy fellow at the Wilson Center and formerly of CNA and the U.S. Department of Defense, on October 19.

A recent report by the UN Food and Agriculture Organization (FAO) warns that over the next 15 years, climate change will add to the number of people living in poverty via its effects on the agriculture and food sectors. By 2030, climate-related effects on food-related livelihoods could lead to an additional 35 to 122 million impoverished people, according to the 2016 State of Food and Agriculture Report.