The Physics of Jet Stream Meandering

Abstract

Large-amplitude jet stream meanders involve diabatic processes because conservation of angular momentum leads to vortex line stretching and shrinking. This requires latent heat release during poleward flow in contrast to cooling by sublimation and radiation during equatorward flow. Moisture and its distribution, together with aerosols, play a key role. The increase of anthopogenic aerosols in the upper troposphere could be a cause for the more frequent large-amplitude jet stream meanders.