Disasters play a key role in debates about climate change, environmental stress, and security. A qualitative comparative analysis (QCA) investigates how major climate-related disasters shape the dynamics of ongoing armed conflicts. Quantitative and qualitative data are presented for twenty-one cases across Africa, Asia, and the Middle East. After climate-related disasters, 29 percent of these armed conflicts escalated, 33 percent de-escalated, and 38 percent did not change. Furthermore, only countries highly vulnerable to disasters experienced changes in conflict dynamics. Armed conflicts tend to escalate when the disaster induces shifts in relative power, whereby one conflict party (usually the rebels) subsequently scales up its military efforts. But if at least one conflict party is weakened by a disaster and the other lacks the capability to exploit this change, armed conflict intensity declines. Findings provide empirical support for a proposed power differential mechanism connecting climate-related disasters to armed conflict dynamics via short-term shifts in power relations between the conflict parties. Climate change can also act as a threat reducer by temporarily causing lower conflict intensity.