dc.contributor.author | Yates, J | |
dc.contributor.author | Palmer, P | |
dc.contributor.author | Manners, J | |
dc.contributor.author | Boutle, I | |
dc.contributor.author | Kohary, K | |
dc.contributor.author | Mayne, N | |
dc.contributor.author | Abraham, L | |
dc.date.accessioned | 2020-01-06T09:56:56Z | |
dc.date.issued | 2020-01-08 | |
dc.description.abstract | We use the Met Office Unified Model to explore the potential of a tidally locked M
dwarf planet, nominally Proxima Centauri b irradiated by a quiescent version of its
host star, to sustain an atmospheric ozone layer. We assume a slab ocean surface
layer, and an Earth-like atmosphere of nitrogen and oxygen with trace amounts of
ozone and water vapour. We describe ozone chemistry using the Chapman mechanism
and the hydrogen oxide (HOx, describing the sum of OH and HO2) catalytic cycle.
We find that Proxima Centauri radiates with sufficient UV energy to initialize the
Chapman mechanism. The result is a thin but stable ozone layer that peaks at 0.75
parts per million at 25 km. The quasi-stationary distribution of atmospheric ozone
is determined by photolysis driven by incoming stellar radiation and by atmospheric
transport. Ozone mole fractions are smallest in the lowest 15 km of the atmosphere
at the sub-stellar point and largest in the nightside gyres. Above 15 km the ozone
distribution is dominated by an equatorial jet stream that circumnavigates the planet.
The nightside ozone distribution is dominated by two cyclonic Rossby gyres that result
in localized ozone hotspots. On the dayside the atmospheric lifetime is determined by
the HOx catalytic cycle and deposition to the surface, with nightside lifetimes due to
chemistry much longer than timescales associated with atmospheric transport. Surface
UV values peak at the substellar point with values of 0.01 W/m2
, shielded by the
overlying atmospheric ozone layer but more importantly by water vapour clouds. | en_GB |
dc.description.sponsorship | Leverhulme Trust | en_GB |
dc.description.sponsorship | Science and Technology Facilities Council (STFC) | en_GB |
dc.identifier.citation | Vol. 492 (2), pp. 1691–1705 | en_GB |
dc.identifier.doi | 10.1093/mnras/stz3520 | |
dc.identifier.grantnumber | ST/R000395/1 | en_GB |
dc.identifier.uri | http://hdl.handle.net/10871/40241 | |
dc.language.iso | en | en_GB |
dc.publisher | Oxford University Press (OUP) | en_GB |
dc.subject | planets and satellites | en_GB |
dc.subject | atmospheres | en_GB |
dc.subject | terrestrial planets | en_GB |
dc.subject | astrobiology | en_GB |
dc.title | Ozone chemistry on tidally locked M dwarf planets | en_GB |
dc.type | Article | en_GB |
dc.date.available | 2020-01-06T09:56:56Z | |
dc.identifier.issn | 0035-8711 | |
dc.description | This is the final version. Available from Oxford University Press via the DOI in this record | en_GB |
dc.identifier.journal | Monthly Notices of the Royal Astronomical Society | en_GB |
dc.rights.uri | http://www.rioxx.net/licenses/all-rights-reserved | en_GB |
dcterms.dateAccepted | 2019-12-10 | |
exeter.funder | ::Leverhulme Trust | en_GB |
exeter.funder | ::Science and Technology Facilities Council | en_GB |
rioxxterms.version | VoR | en_GB |
rioxxterms.licenseref.startdate | 2019-12-10 | |
rioxxterms.type | Journal Article/Review | en_GB |
refterms.dateFCD | 2020-01-06T09:01:47Z | |
refterms.versionFCD | AM | |
refterms.dateFOA | 2020-01-29T14:42:57Z | |
refterms.panel | B | en_GB |