Facing danger and turmoil at home, hundreds of thousands of refugees have crossed the Mediterranean Sea so far this year, seeking sanctuary and a new life in Europe. The spike in refugees has been largely driven by the bloody civil war in Syria, which has displaced over 10 million people. In the near term, the European Union, with the help of the United Nations and the United States, must find a way to address this humanitarian crisis. Developing such collective solutions now is essential as a foundation for the future: the current crisis is but a prelude to the far more profound displacements to come as a result of encroaching environmental limits. The increased frequency and severity of extreme weather events—such as droughts and hurricanes—could make whole cities and regions uninhabitable, and conflicts over limited resources like water and land could foment geopolitical instability. Indeed, climate change contributed to the outbreak of current civil war in Syria. Grappling with climate change requires not only mitigating its severity but building institutions for mitigating its human toll.