This article is published as part of Fridays With MUNPlanet and its special series dedicated to world politics. The aim of this series is to bring you the analysis of global affairs by the established and upcoming scholars, decision-makers and policy analysts from various world regions. This week, Lucile Maertens (University of Geneva/Global Studies Institute and Sciences Po Paris/CERI) writes about climate change and the process of its becoming a security issue in the United Nations system. Climate change has presented a source of divides among great powers since the 1990s, but, as the author argues, in 2015 "the UN not only draws attention to the dangers of climate change but also creates hope" and "fully acknowledging the security risks caused by climate change, the United Nations is also trying to turn these dangers into opportunities for diplomatic cooperation."