Similarities in meteorological composites among different atmospheric river detection tools during landfall over western coastal North America
Many atmospheric river detectors (ARDTs) have been developed over the past few decades to identify atmospheric rivers (ARs). Different ARDTs have been observed to capture a variety of frequencies, shapes, and sizes of ARs. Due to this, questions have arisen about the underlying phenomena associated with the detected ARs: do all ARDTs detect the same meteorological phenomena? In this paper, we assess eight ARDTs and investigate the underlying synoptic scale phenomena during landfalling ARs along the west coast of North America. We find that during landfalling ARs events, prevalent low-pressure and high-pressure systems converge and enhance moisture influx towards the landfalling site. We identify that all eight ARDTs identify AR conditions associated with baroclinic waves, with the region of intense integrated vapor transport (IVT) located downstream of the upper level (500 hPa) trough. The strength of the pressure gradients in the confluence region enhances
the influx of the IVT. We conclude that the eight ARDTs identify similar meteorological phenomena.