Global changes in floods and their drivers

•We perform the first global assessment of multidimensional changes in riverine floods and their drivers.•Global floods tended to decrease in multiple dimensions, due to the larger negative impacts of antecedent wetness conditions than the positive impacts of heavy precipitation.•Flood magnitude and duration change were primarily driven by antecedent wetness conditions, while the dominant mechanism of flood frequency change is heavy precipitation.•Snowmelt exhibits strong local effects on reducing multidimensional floods over high-latitude regions.