Biological and Environmental Research - Earth and Environmental System Sciences
Earth and Environmental System Modeling

Atmospheric river lifecycle responses to the Madden‐Julian Oscillation

TitleAtmospheric river lifecycle responses to the Madden‐Julian Oscillation
Publication TypeJournal Article
Year of Publication2020
JournalGeophysical Research Letters
Volume48
Number3
Abstract / Summary

We investigate how the Madden‐Julian Oscillation (MJO), the dominant mode of tropical subseasonal variability, modulates the lifecycle of cool‐season North Pacific atmospheric rivers (ARs). When the enhanced (suppressed) convection center is located over the Indian Ocean (western Pacific), more AR events originate over eastern Asia and with fewer over the subtropical northern Pacific. When the enhanced (suppressed) convection is over the western Pacific (Indian Ocean), the opposite changes occur, with more AR events originate over the subtropical northern Pacific and fewer over eastern Asia. Dynamical processes involving anomalous MJO wind and seasonal mean moisture are found to be the dominant factors impacting these variations in AR origins. The MJO‐related anomalous geopotential height patterns are also shown to modulate the propagation of the AR events. These MJO–AR lifecycle relationships are further supported by model simulations.

URLhttps://doi.org/10.1029/2020GL090983
DOI10.1029/2020GL090983
Journal: Geophysical Research Letters
Year of Publication: 2020
Volume: 48
Number: 3
Publication Date: 12/2020

We investigate how the Madden‐Julian Oscillation (MJO), the dominant mode of tropical subseasonal variability, modulates the lifecycle of cool‐season North Pacific atmospheric rivers (ARs). When the enhanced (suppressed) convection center is located over the Indian Ocean (western Pacific), more AR events originate over eastern Asia and with fewer over the subtropical northern Pacific. When the enhanced (suppressed) convection is over the western Pacific (Indian Ocean), the opposite changes occur, with more AR events originate over the subtropical northern Pacific and fewer over eastern Asia. Dynamical processes involving anomalous MJO wind and seasonal mean moisture are found to be the dominant factors impacting these variations in AR origins. The MJO‐related anomalous geopotential height patterns are also shown to modulate the propagation of the AR events. These MJO–AR lifecycle relationships are further supported by model simulations.

DOI: 10.1029/2020GL090983
Citation:
Zhou, Y, H Kim, and DE Waliser.  2020.  "Atmospheric river lifecycle responses to the Madden‐Julian Oscillation."  Geophysical Research Letters 48(3).  https://doi.org/10.1029/2020GL090983.