Conflict, drought and locusts are leading concerns for African food security but the relative importance and spatiotemporal scale of crises resulting from each hazard is poorly characterized. Here we use continuous, subnational data to demonstrate that the rise of food insecurity across sub-Saharan Africa that began in 2014 is attributable to an increase in violent conflict, particularly in South Sudan and Nigeria. Although drought remains a leading trigger of food crises, the prevalence of drought-related crises did not increase from 2009 to 2018. When exposed to drought, pastoralists experienced more widespread, severe and long-lasting food crises than people living in agricultural zones. Food insecurity remained elevated in pastoral regions for 2 years following a drought, while agricultural regions returned to pre-drought food-security levels in ~12 months. The few confirmed famines during the 2009–2018 period coincided with both conflict and drought, while locusts had little effect on food security during this period.

冲突、干旱和蝗灾是非洲粮食安全的主要问题，但每种灾害造成的危机的相对重要性和时空规模的特征却很不明确。在这里，我们使用连续的地方数据来证明自 2014 年开始的撒哈拉以南非洲地区粮食不安全状况的加剧归因于暴力冲突的增加，特别是在南苏丹和尼日利亚。尽管干旱仍然是粮食危机的主要诱因，但从 2009 年到 2018 年，与干旱相关的危机的发生率并未增加。与生活在农业区的人们相比，在遭受干旱时，牧民经历了更广泛、更严重和更持久的粮食危机。干旱后牧区的粮食不安全状况持续了 2 年，而农业地区在约 12 个月内恢复到干旱前的粮食安全水平。2009-2018 年期间为数不多的确认饥荒与冲突和干旱同时发生，而蝗虫在此期间对粮食安全几乎没有影响。