The Rossby wave train patterns forced by shallower and deeper Tibetan Plateau atmospheric heat-source in summer in a linear baroclinic model

Abstract

By using a linear baroclinic model (LBM), this study investigates the different Rossby wave train (RWT) patterns associated with the Tibetan Plateau (TP) upper-atmospheric heat source (TPUHS) that is anomalously shallower and deeper in boreal summer. Observational results indicate the different RWT patterns between the developing and decaying periods of synoptic TPUHS events, when the anomalous TPUHS develops from a relatively shallower to a deeper TP heat source. Based on the different vertical heating profiles between these two periods in observation, this study forces the LBM with prescribed TPUHS profiles to mimic a shallower and deeper summer TP heat source. The results show that the atmospheric responses to a shallower and deeper TPUHS do exhibit different RWT patterns that largely resemble those in observation. Namely, corresponding RWT pattern to a shallower TPUHS stretches from the TP to the west coast of America, while that to a deeper TPUHS extends from the TP region to Alaska.

Keywords

• Tibetan Plateau upper atmospheric heat source
• shallower and deeper heat source
• Rossby wave train pattern