Changing Flood‐Generating Mechanisms Impact Flood Characteristics in Snow‐Dominated Catchments

Global warming is shifting the characteristics of snowmelt floods, while simultaneously altering flood‐generating mechanisms in cold regions. Here, we disentangle the contributions of inter‐type mechanism transitions from intra‐type characteristic shifts to overall changes in flood behavior across Northern Hemisphere snow‐dominated catchments. We demonstrate that inter‐type transitions—specifically the widespread shift from snowmelt‐ to rainfall‐driven floods—substantially alter flood rising rates and timing. While this transition has not systematically changed long‐term flood magnitudes, it has significantly steepened the rising limb of flood hydrographs. Furthermore, although rising temperatures have advanced the timing of snowmelt and rain‐on‐snow floods, the shift toward rainfall dominance has largely offset this trend, leading to a stronger synchronization between flood timing and extreme precipitation. By explicitly separating these mechanisms, our framework advances the mechanistic understanding of changing flood dynamics, offering critical insights for flood forecasting and water management.