Atmospheric river lifecycle characteristics shaped by synoptic conditions at genesis

The range of synoptic patterns that North Pacific landfalling atmospheric rivers form under are objectively identified using genesis day 500 hPa geopotential height anomalies in a self-organizing map (SOM). SOM arranges the to differentiate between two groups climate modes—the first group with ENSO (El Niño Southern Oscillation), PDO (Pacific Decadal PNA American) and NP (North index) second AO (Arctic EPO (East WPO (West Oscillation). These have their positive negative modes organized opposite corners SOM. ARs produced each distinct lifecycle characteristics (such as landfall location, duration, velocity, meridional/zonal movement) precipitation impacts (magnitude spatial distribution). conditions favour AR trajectories closer tropics tend produce higher amounts precipitation. large-scale circulation associated shows close relationship location intensity upper-level jet west/central pacific well anomalous, low-level southwesterly winds east pacific.