[A-AS10] General Meteorology

[AAS10-P05] The development of contrail cirrus module on the cloud-resolving model.

*Uchida Junya¹ (1.Japan Agency for Marine-Earth Science and Technology)

Keywords:Contrail cirrus, Cloud-resolving model, Contrail cirrus module

Condensation trail (Contrail) is a line-shaped cirrus that forms behind the jet plane flying in the colder and moister environment. The contribution of contrail to the aviation related radiative forcing (RF) is larger than that of global aviation CO₂ emissions, amounts to about 2% of total anthropogenic RF and is expected to increase year to year (Lee et al. 2021). However, the estimation of such climate impact is highly uncertain partly because there are only a few contrail studies conducted with the global cloud-resolving atmospheric model, which allows an explicit water and/or ice supersaturation. Modifying the contrail model CCMOD of Eulerian-type (Burkhardt and kärcher 2009; Bock and Burkhardt 2016), we develop the contrail module specific to the cloud-resolving global atmospheric model NICAM (Satoh et al. 2014). Our modification adds several new prognostic variables, e.g., a water vapor in the plume, to improve the nucleation process while removing the processes irrelevant to the cloud-resolving model, such as the processes associated with a sub-grid cloud fraction. With the intent to determine the model uncertainties, we conduct several sensitivity tests on the contrail module in conjunction with NICAM, varying the horizontal resolutions and the cloud microphysics to analyze how they impact a region of possible contrail generation and growth.