[MIS07-P19] DCPAM を用いた古火星気候の数値実験
キーワード：初期火星、放射伝達、大気大循環モデル、放射対流平衡
We have been performing one- and three-dimensional numerical experiments of early Mars. In order to do those, we have developed a radiation model for a thick CO2 atmosphere, and implemented that into our general circulation model, DCPAM. The radiation model includes advances on radiative transfer calculations which were reported by our groups. The DCPAM is an atmospheric GCM, which uses primitive equation system, and a number of parameterizations, such as radiation, turbulent diffusion, surface energy budget, and condensation processes.
Numerical experiments of one-dimensional radiative convective equilibrium of pure CO2 atmosphere without radiative effects of cloud shows surface pressure dependence of surface temperature which is similar to that reported by a previous study. That is, surface temperature is highest at a surface pressure of several bars. But, the highest surface temperature is far below the freezing point.
Three-dimensional numerical experiments are also performed by the use of the general circulation model, DCPAM, with the radiation model. In the experiments, we assumed both cases with and without radiative effects of cloud. In experiments without radiative effects of cloud, global mean surface temperatures are similar to those obtained by one dimensional radiative convective equilibrium experiments. But, surface temperature increases with increasing the surface pressure. Further, in experiments with radiative effects of cloud, surface temperature is higher than freezing point. The behavior is different from that reported by previous study.
We will check the energy budget, circulation structures, and atmospheric structures obtained by the models in order to consider the difference of results between ours and previous study's.
Numerical experiments of one-dimensional radiative convective equilibrium of pure CO2 atmosphere without radiative effects of cloud shows surface pressure dependence of surface temperature which is similar to that reported by a previous study. That is, surface temperature is highest at a surface pressure of several bars. But, the highest surface temperature is far below the freezing point.
Three-dimensional numerical experiments are also performed by the use of the general circulation model, DCPAM, with the radiation model. In the experiments, we assumed both cases with and without radiative effects of cloud. In experiments without radiative effects of cloud, global mean surface temperatures are similar to those obtained by one dimensional radiative convective equilibrium experiments. But, surface temperature increases with increasing the surface pressure. Further, in experiments with radiative effects of cloud, surface temperature is higher than freezing point. The behavior is different from that reported by previous study.
We will check the energy budget, circulation structures, and atmospheric structures obtained by the models in order to consider the difference of results between ours and previous study's.