BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:Atmospheric collapse on tidally locked rocky planets - Pierre Aucl
 air-Desrotour (CSH\, Bern)
DTSTART:20200428T150000Z
DTEND:20200428T160000Z
UID:TALK141718@talks.cam.ac.uk
CONTACT:Dr Annelies Mortier
DESCRIPTION: Over large timescales\, a terrestrial planet may be driven to
 wards spin-orbit synchronous rotation by tidal forces. In this particular 
 configuration\, the planet exhibits permanent dayside and nightside\, whic
 h may induce strong day-night temperature gradients. The nightside tempera
 ture depends on the efficiency of the day-night heat redistribution and de
 termines the stability of the atmosphere against collapse. To better const
 rain the atmospheric stability and surface conditions of terrestrial plane
 ts located in the habitable zone of their host star\, it is thus crucial t
 o understand the complex mechanism of heat redistribution. While general c
 irculation models (GCM) are far too costly to be used to explore the param
 eter space\, analytic models offer a global overview of the physics with a
  fairly reduced computational cost. We present here a new model hierarchy 
 that builds on theoretical studies (e.g. Wordsworth 2015\, Koll & Abbot 20
 16) by including additional physical ingredients such as shortwave radiati
 ve transfers\, scattering\, and advection due to atmospheric circulation. 
 We thus show that the analytic theory captures (i) the dependence of tempe
 ratures on atmospheric opacities and scattering\, (ii) the behaviour of th
 e collapse pressure observed in GCM simulations at low stellar fluxes\, an
 d (iii) the increase of stability generated by dayside sensible heating.\n
 \n\n
LOCATION:ONLINE - Details to be sent by email
END:VEVENT
END:VCALENDAR