A case study of formation and maintenance of a lower stratospheric cirrus cloud over the tropics
M. Sandhya1,2,S. Sridharan1,M. Indira Devi2,K. Niranjan2,and A. Jayaraman1M. Sandhya et al. M. Sandhya1,2,S. Sridharan1,M. Indira Devi2,K. Niranjan2,and A. Jayaraman1
1National Atmospheric Research Laboratory, Gadanki 517 112, Pakala Mandal, Chittoor District, Andhra Pradesh, India
2Department of Physics, Andhra University, Visakhapatnam, Andhra Pradesh 530003 India
1National Atmospheric Research Laboratory, Gadanki 517 112, Pakala Mandal, Chittoor District, Andhra Pradesh, India
2Department of Physics, Andhra University, Visakhapatnam, Andhra Pradesh 530003 India
Correspondence: S. Sridharan (susridharan@narl.gov.in)
Received: 28 Jan 2015 – Revised: 23 Apr 2015 – Accepted: 02 May 2015 – Published: 29 May 2015
Abstract. 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.
A rare occurrence of stratospheric cirrus at 18.6km persisting for about 5 days is observed over India from 3 to 7 March 2014. Due to potential vorticity intrusion, large-scale updrafts and increase in humidity are observed at 18.6km. Relative humidity with respect to ice is ~ 150%, indicating that the cirrus cloud may be formed though homogeneous nucleation of sulfuric acid. The persistence of the cirrus cloud is due to the cold anomaly associated with the presence of a 4-day wave.
A rare occurrence of stratospheric cirrus at 18.6km persisting for about 5 days is observed over...
