Access to and competition over natural resources has been one of the most common triggers for conflict. Throughout the centuries, countries and communities have fought over productive agricultural land, trade routes, spices, textiles, opium, and oil, to name just a few. But the battle over one natural resource—fish—has long been overlooked. As trends in the global fish industry increasingly mirror the conflict-ridden oil sector, fish may become the newest addition to the list of resources driving geopolitical competition. There are five parallels between oil and fish that call for increasing the sustainability of the fishing industry, or we might find ourselves facing what U.S. Coast Guard Captain Jay Caputo has called “a global fish war.”

Without connections to wider electrical grids, communities in the remote, rural Arctic depend on diesel generators for power—which makes electricity “ten times more expensive” than in the rest of Canada or the United States, said Martha Lenio of the World Wildlife Fund-Canada Arctic Team during a recent Wilson Center Ground Truth Briefing. In addition, spilled diesel “can harm wildlife, impact food and water security, and compromise permafrost integrity,” said Lenio. These challenges have led some communities in the Arctic to seek cheaper, safer, and more innovative energy solutions, said panelists during the briefing organized by the Wilson Center’s Polar Initiative and Canada Institute.

As the national security ramifications of climate change grow more pronounced, climate manipulation technologies, known as geoengineering, will become more attractive as a method of staving off climate-related security emergencies.  However, geoengineering technologies could disrupt the global ecological status quo, and could pose a potentially coercive (and very serious) threat to peace. Is it possible to obtain the potential benefits of these game-changing technologies, while avoiding spurring violence and conflict?  In a recent article in Strategic Studies Quarterly, we argue that just war theory—which defines the concepts of “right” and “wrong” in warfare—could provide ethical standards for security decision-makers as they consider whether or how geoengineering should be used to address the climate challenge.

A quarter of the coal that powers China’s economy is mined in Inner Mongolia, one of the country’s most water-scarce provinces with only slightly under two percent of China’s total water resources. The coal-rich city of Ordos, which produces nearly 70 percent of all the coal in Inner Mongolia, is bookended by expanding deserts—Kubuqi to the north and Maowushu to the south—and may one day run out of water and face a “Day Zero” like Cape Town in South Africa. Both the central and local governments are promoting a number of efforts to create new water supplies in Ordos, such as treating brackish waters and trading water rights. To learn more, the China Energy & Environment Forum recently interviewed Shaofeng Jia, the Deputy Director of Water Resources Research Center at the Chinese Academy of Sciences, who recently completed an extensive study on water-energy confrontations in Inner Mongolia.

Blockchain, the newest technology poised to revolutionize numerous industries, could help decentralize electricity systems across Asia, Europe, Australia and the United States. In Brooklyn, peer-to-peer microgrids allow prosumers—energy consumers who generate small amounts of electricity from renewable sources—to trade energy with other users. Blockchain technology provides distributed ledgers that validate, record, and share each transaction, using smart contracts that automatically execute energy trades when the price and volume of the electricity transaction meet the contracted requirements.

Just days before the 2016 Summer Olympics began in Rio de Janeiro, the Brazilian city faced an unsavory problem: how to handle its overwhelming sewage. Nearly half of Rio’s municipal wastewater flowed untreated into Guanabara Bay, where the waters were so polluted by sludge that direct contact was deemed a health hazard to Olympic athletes.

For the first time, the Joint Doctrine of the Indian Armed Forces acknowledges that the “environment has emerged as a critical area of the security paradigm,” and warns that if environmental degradation and related issues increase security risks, the military will need to respond. Released in 2017, the doctrine lists a series of non-traditional security challenges linked to the environment that could influence conflict and war, including “climate change, ecosystem disruption, energy issues, population issues, food-related problems, economic issues of unsustainable modes of production, and civil strife related to environment.” While the military has taken steps to address its impacts on the environment, it can do much more to support the nation’s environmental goals and mitigate environment-related security risks.

Sewage—refuse liquids or waste matter usually carried off by sewers—is at the front lines of a global movement for clean energy. Innovative U.S. cities are digging into their dirtiest depths to create new sources of power that optimize economic benefits, generate clean energy, and control pollution. This wastewater-to-power movement is just beginning to catch on in China. But with some of the largest and most densely populated cities in the world, the country could be poised to lead a sludge-to-energy revolution.