Decadal Variation of Atmospheric Rivers in Relation to North Atlantic Tripole SST Mode

The North Atlantic tripole (NAT) is the leading mode of sea-surface temperature (SST) in decadal time scale. Although NAT forced by oscillation (NAO), it also has an effect on atmosphere; for example, early winter SST signal can influence storm tracks March. As not only changes baroclinicity lower layer but modifies moisture being released into atmosphere, we surmise that impact transport and atmospheric rivers Using ERA5 reanalysis data, variations Atmospheric Rivers (ARs) boral relation to phases were studied. During positive phase, central western increases humidity causes anticyclonic wind response, which enhances northeastward moisture. a result, ARs tend be longer more toward northwestern Europe. This enhanced extreme rain UK Norway. negative anomalies south east provide moisture, induce southward shift enhance Iberian Peninsula. Gulf Stream (GS) front stronger during increasing frequency enlarging rate ARs.