To meet the climate challenge, city leaders are committing to ambitious emissions targets, designing decentralized action plans, and sharing lessons in transnational networks. Since growing cities are a large source of global emissions, their efforts could contribute substantially to global climate objectives. As the world’s climate experts gather next week in Bonn, Germany, for the 23rd Conference of the Parties (COP-23), urban initiatives will be a key focal point of the agenda-setting conversation.

Earlier this month, more than 40 people perished and 20,000 people were ordered to evacuate as Northern California faced some of its deadliest fires in decades. Potentially fueled by climate change, these fires—only the only the latest in a string of fires to strike the state—will reshape landscapes and lives, as I know well from personal experience on the other side of the world.

Water is a “strategic instrument in the creation of a safer, healthier, more nutritious, less aggressive world,” said Winrock International President and CEO Rodney Ferguson at the first event in a four-part series on water security organized by the Wilson Center and the Sustainable Water Partnership. Panelists at the event identified innovative and integrated efforts necessary to increase global water security in the face of growing water scarcity.

A threat looms on the sun-splashed horizon of the Republic of the Marshall Islands. The specter of climate change wraps its fingers around the islands, raising sea levels, salinizing soils, and sapping freshwater resources. These changes will make it even harder to sustain crops, which could push the population to even greater reliance on  processed foods, which has already spurred a diabetes epidemic on the islands. The major role played by the United States in the history of the Marshalls, where nuclear bombs were famously tested during the Cold War, may continue, as the impacts of another existential threat—climate change—continue to increase.

As the climate changes, cities will suffer. “These are important places that have a lot of people, property, and local economies that are going to struggle,” said Jessica Grannis, the adaptation program manager at Georgetown’s Climate Center, at a recent Wilson Center event on the role of subnational decision-makers in achieving international goals.  “The good news is that, here in the United States, many cities are recognizing these threats to their people and populations, and they’re beginning to take action,” said Grannis.

While attention in the United States is focused on the disasters in Puerto Rico and the Caribbean, a crisis across the Atlantic is rapidly becoming one of the worst humanitarian disasters since World War II. In the Lake Chad basin of West Africa, about 17 million people are affected by the emergency, struggling with food insecurity, widespread violence, involuntary displacement, and the consequences of environmental degradation. An estimated 800,000 children suffer from acute malnutrition; and although international donors pledged $672 million in February, the famine and humanitarian misery continues unabated. Suicide bombings and attacks by Boko Haram, which have killed at least 381 civilians since April 2017, have forced many people to leave their homes and farmers to leave their lands, interrupting livelihoods and reducing food supplies.

From 1870 to 2015, the CO2 concentration in the atmosphere  increased significantly, said Professor Maria Sanz, scientific director at the Basque Center for Climate Change in a recent webinar organized by WWF Forest and Climate. Forests have been responsible for global greenhouse gas emissions through forestry and other land use activities. However, she noted that forests also absorb nearly one-third of the emissions generated from fossil fuels.