Delta sustainability from the Holocene to the Anthropocene and envisioning the future

River deltas offer numerous ecosystem services and host an estimated global population of 350 million to more than 500 million inhabitants in over 100 countries. To maintain their sustainability into the future, deltas need to withstand sea-level rise from global warming, but human pressures and diminishing sediment supplies are exacerbating their vulnerability. In this Review, we show how deltas have served as environmental incubators for societal development over the past 7,000 years, and how this tightly interlocked relationship now poses challenges to deltas globally. Without climate stabilization, the sustainability of populous low-to-mid-latitude deltas will be difficult to maintain, probably terminating the delta–human relationship that we know today.