Variation in the <scp>Holton–Tan</scp> effect by longitude

The teleconnection between the Quasi-Biennial Oscillation (QBO) and boreal winter polar vortex, Holton–Tan effect, is analyzed in Whole Atmosphere Community Climate Model (WACCM) with a focus on how stationary wave propagation varies by QBO phase. These signals are difficult to isolate reanalyses because of large internal variability short observational records, especially when decomposing data A 1,500-year ensemble leveraged defining index at five different isobars 10 70 hPa. effect robust part atmospheric response WACCM warming stratosphere during easterly (QBOE). nudging technique used reduce stratospheric one simulation. This enables isolation impact atmosphere absence QBO: referred as “direct effect” response, “indirect effect.” simulation reveals that QBOE pushes tropospheric jet equatorward, opposing poleward shift QBOE, over North Pacific. longitude. induces stronger planetary forcing mean flow extratropical lower Indonesia Alaska. Pacific responds this before other longitudes. What follows position vortex toward Eurasia (North America) (westerly) QBO. initiates downstream responses America, Atlantic, Siberia. spatiotemporal evolution found transient simulations which “switched on.” seems more intrinsically linked while longitudes appear dependent mutual interaction stratosphere.