摘要 : This publication provides a detailed study of one cirrus cloud observed by lidar atthe Observatory of Haute-Provence (~44°N) in January 2006 in the vicinity of thetropopause (12-14 km/~136-190 hPa/328-355 K). The higher part of th... 展开 This publication provides a detailed study of one cirrus cloud observed by lidar atthe Observatory of Haute-Provence (~44°N) in January 2006 in the vicinity of thetropopause (12-14 km/~136-190 hPa/328-355 K). The higher part of the air massobserved comes from the wet subtropics while the lower part comes from the midlatitudes.Both are advected by the Azores anticyclone, encounter cold temperatures (~205 K)above the North Atlantic Ocean, and flow eastward along the anticyclonic flank of thepolar jet stream. A simulation of this cloud by an isentropic model is tested to see ifsynoptic-scale atmospheric structures could explain by itself the presence of such clouds.The developments made in the Modelisation Isentrope du transport Meso-echelle del'Ozone Stratospherique par Advection (MIMOSA) model to take into account the threephases of water and their interactions allow reproduction of the occurrence of the cirrusand its temporal evolution. MIMOSA-H20 reproduces the atmospheric water vaporstructures observed with Atmospheric Infrared Sounder (AIRS) with, however, anapparent wet bias of around 50%. Reliable water vapor fields appear to be the maincondition to correctly simulate such cirrus clouds. The model reproduces the cirrus cloudaltitude for fall speeds around 1 cm/s and gives ice water content around 3-4 mg/m3. Fallspeed is also a critical parameter, and a better parameterization with altitude or otheratmospheric conditions in the modeling of such cirrus clouds is required. This study alsoshows that supersaturation threshold impacts strongly the vertical and horizontal extensionof the cirrus cloud but more slightly the ice water path. 收起