The Lanjiang river in Eastern Zhejiang, China, reached its peak water level of 100 feet the night of June 25, 2017. Lanxi residents remember this day as “6.25,” marking the worst flood since 1955. Elsewhere in China that month, 7.3 million people were affected by floods, landslides, and heavy rains in northwestern Sichuan Province alone. Northern Guangxi suffered direct economic losses of 2.9 billion RMB (US$460 million). In the autonomous regions, 92,000 people were relocated. Flash floods caused the deaths of 10 people and forced 76,800 people to evacuate from Shanxi Province.

In late 2017, I visited the several Rohingya refugee camps (Leda, Mainner Ghona, & Kutupalong-Balukhali Makeshift Settlements) in Ukhia Upazila (Cox’s Bazar District), Bangladesh. These camps are home to more than a million refugees escaping ethnic violence in Myanmar.

Natural bioshields—wetlands, forests, and urban green spaces—are critical tools for reducing the impacts of disasters on vulnerable communities. Between 1994 and 2014, nearly 7,000 natural disasters occurred worldwide, causing an average of almost 68,000 deaths each year. Climate change, growing populations, and widening economic inequality are all expected to increase the impacts of disasters. Bioshields—nature’s own solutions to natural hazards—can help protect people from these dangerous floods, storms, and heat waves.

“Climate is unquestionably linked to armed conflict,” said Halvard Buhaug, a professor at the Peace Research Institute Oslo and the Norwegian University of Science and Technology, at a recent Wilson Center event marking the end of the three-year Climate Anomalies and Violent Environments (CAVE) research project. But, he stresses that under a changing climate, exactly how and through what pathways is still a subject of much debate in the academic community.

In 2014, we met with some of the technical leads of a major Chinese river basin authority in Beijing and asked them whether they were more worried about pollution or climate change impacts. Both, the engineers replied. Pollution affects us every day, they said, but changes in the climate erode our ability to supply drinking and irrigation water, manage floods, and generate electricity.

China must address its environmental and climate change challenges, such as reducing water pollution and building resilience to droughts, floods, and long-term climate shifts. But existing sources of finance have not met the growing demand for environmental projects.

Cape Town is running dry. But thanks to its sophisticated water management efforts, the city may ride out the crisis. However, other cities that lack these capacities are less likely to survive Day Zero. Especially in developing countries, where urban water services are often provided by informal or illegal actors, running out of water could have dangerous ripple effects for peace and security.

After pirates hijacked an Iranian fishing vessel last year near Bosasso, a major seaport in Puntland, Somalia, local authorities observed that the offending boat was casting nets without a license. While piracy has diminished since 2008-2012, when these waters became some of the most lawless in the world, a spate of incidents in 2017-8 has made it clear that the conditions that led to piracy—including incursions from foreign fishing boats—are still a major problem.

“Most fundamentally, we turned the ‘resource scarcity drives conflict’ argument on its head and asked, ‘Can environmental interdependence drive cooperation in ways that can be harnessed to build trust and contribute to conflict prevention and peacebuilding?’” said Geoff Dabelko, Associate Dean at Ohio University’s Voinovich School of Leadership and Public Affairs, about Environmental Peacemaking, which was one of the first books to investigate these questions. In the 15 years since he and Ken Conca, a professor at American University’s School of International Service, published their edited volume, the idea that shared environmental issues could be used to build peace has become a focus of innovative research, policy, and programs.