Explanation of the enhanced eastward GW forcing before SSW (see also de Wit et al, 2014) at Kiruna for example?
It coincides with the weakening of the eastward wind which allows eastward propagating GWs to impose an eastward drag. It also highlights the major role of PWs in the zonal wind weakening.
Explanation of the enhanced eastward GW forcing before SSW (see also de Wit et al, 2014) at Kiruna for example? It coincides with the weakening of the eastward wind which allows eastward propagating GWs to impose an eastward drag. It also highlights the major role of PWs in the zonal wind weakening.