Seminar: CPS/WTK Seminar
date: 2018 July (Mon) 16:00-
room: CPS Conference Room

speaker: Masahiro Takagi (Kyoto Sangyo University ,Professor)
title: Three-dimensional structures of thermal tides simulated by a Venus GCM
abstract: Thermal tides in the Venus atmosphere are investigated by using a GCM named AFES-Venus. The result shows that the wind and temperature distributions of the thermal tides depend complexly on latitude and altitude in the cloud layer, mainly because they consist of vertically propagating and trapped modes with zonal wave numbers of 1-4, each of which predominates in different latitudes and altitudes under the influence of mid- and high-latitude jets. A strong circulation between the subsolar and antisolar (SS-AS) points, which is equivalent to a diurnal component of the thermal tides, is superposed on the superrotation. The vertical velocity of SS-AS circulation is about 10 times larger than that of the zonal-mean meridional circulation (ZMMC) in 60-70 km altitudes. The ZMMC is weak and has a complex structure in the cloud layer; the Hadley circulation is confined to latitudes equatorward of 30 degrees, and the Ferrel-like one appears in middle and high latitudes.
keywords: Venusian thermal tide, SS-AS circulation, zonal-mean meridional circulation

organizer: Yoshiyuki Takahashi