In this study,we conduct a numerical simulation of the dry dynamical processes induced by boundary layer convection on the generation and propagation of gravity waves on the northeastern slope of the Qinghai-Tibet Plateau under complex terrain conditions.This simulation is based on field-observed sounding data from the Qilian station in July 2007,coupled with a high-resolution 3D boundary layer model.The results reveal significant variations in the spatial structure of convection and gravity waves over the complex terrain of the northeastern plateau slope,contingent on different background forcing scenarios.Specifically,when the background wind direction is perpendicular to the mountain,an increase in wind speed enhances atmospheric instability energy near the top of the mixed layer on the leeward slope of the ridge,thereby exciting a more pronounced gravity wave signal in the downstream region.In contrast,when the background wind direction aligns parallel to the ridge,vigorous convection develops over the summit,resulting in a more stable atmospheric state at the top of the mixed layer on the leeward ridge slope.This,in turn,weakens the topographic gravity wave signal,yielding a shorter wave train.Additionally,there is less water vapor near the top of the entire mixed layer,diminishing the conditions conducive to convective cloud formation.Also,decreased background atmospheric buoyancy frequency leads to more vigorous yet less organized convection across the region,reducing the upward transmission distance of gravity waves downstream of the leeward slope and yielding in less significant signals.Furthermore,under these conditions,there is a uniform distribution of water vapor near the top of the mixed layer with minimal amplitude changes,which mitigates conditions conducive to convective cloud formation.