A case study of formation and maintenance of a lower stratospheric cirrus cloud over the tropics
نویسندگان
چکیده
A rare occurrence of stratospheric cirrus at 18.6 km height persisting for about 5 days during 3– 7 March 2014 is inferred from the ground-based Mie lidar observations over Gadanki (13.5 N, 79.2 E) and spaceborne observations. Due to the vertical transport by large updrafts on 3 March in the troposphere, triggered by a potential vorticity intrusion, the water vapour mixing ratio shows an increase around the height of 18.6 km. Relative humidity with respect to ice is ∼ 150 %, indicating that the cirrus cloud may be formed though homogeneous nucleation of sulfuric acid. The cirrus cloud persists due to the cold anomaly associated with the presence of a 4-day wave.
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