Modeling studies related to carbon dioxide phase change on Mars

摘要: Carbon dioxide (CO₂) is the most abundant gaseous species in atmosphere of Mars. Phase change CO₂, predominantly between gas and solid, eminent feature current Martian atmosphere. Correct thorough understanding CO₂ cycle on Mars crucial to scientific research Mars, including (but not limited to) climatology, meteorology, paleo-climatology, geomorphology, geology, astrobiology. This dissertation focuses modeling phase coupling process with a General Circulation Model (GCM) ― Weather Forecast Research (MarsWRF) model study climate Two major forms are included: direct deposition/sublimation to/from surface (exchange frost) atmospheric condensation/evaporation "snow", which later will either precipitate ground become part reservoir, or evaporate before it reaches surface). The first component has been historically simulated by energy balance model. calculations MarsWRF, especially physics module associated subsurface heat conduction, improved. GCM fine-tuned changing values seasonal ice cap albedos emissivities total mass system (later conductivity polar soil). Resulted pressure cycle, good indicator reservoir matches situ measurements made Viking Landers extremely well. fitting algorithm can be used for tuning GCMs exploration more complicated physical processes. second solved simple as However, widely accepted that sophisticated microphysics models may required accurate simulations. A complete model, calculates nucleation particle growth process, incorporated MarsWRF. Preliminary simulation results show promising agreement spacecraft observations. When an insolation-dependent frost albedo included, MarsWRF able produce perennial near south pole time any successfully predicted residual cap. mechanism necessary reproduce cap, shed some light ages cycles caps. developed simulate non-condensable mixing ratio variation during change. coupled agrees qualitatively Gamma Ray Spectrometer data other results. It provides benchmark check itself independent way dynamics