Microphysical properties of subvisible cirrus

Interactive comment on “Aircraft measurements of microphysical properties of subvisible cirrus in the tropical tropopause layer” by R. P. Lawson

This paper describes observations of subvisible cirrus (SVC) clouds with the NASA WB-57F aircraft during the Costa Rica Aura Validation Experiment (CR-AVE) in 2006. SVC clouds were encountered and characterised with state-of-the-art optical array imageing probes in extended areas of the tropical tropopause layer with temperatures as low as −90◦C. Nearly spherical crystal shapes were measured fo...

Properties of subvisible cirrus clouds formed by homogeneous freezing

Number concentrations and mean sizes of ice crystals and derived microphysical and optical properties of subvisible cirrus clouds (SVCs) formed by homogeneous freezing of supercooled aerosols are investigated as a function of temperature and updraft speed of adiabatically ascending air parcels. The properties of such clouds are insensitive to variations of the aerosol number and size distributi...

Interactive comment on “Aircraft measurements of microphysical properties of subvisible cirrus in the tropical tropopause layer” by R. P. Lawson et al

1) How are SVC defined in these measurements? As stated in the manuscript, the presence of SVC was “detected” using the CPI, which defined the physical boundaries of SVC encountered by the C-130. Because the CPI was operational on every SVC flight, this optimized the definition of physical boundaries of SVC encountered by the WB-57F. Also, as explained in the manuscript, quantitative 2D-S measu...

Properties of cirrus and subvisible cirrus from nighttime Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP), related to atmospheric dynamics and water vapor

Aircraft measurements of microphysical properties of subvisible cirrus in the tropical tropopause layer

Subvisible cirrus (SVC) clouds are often observed within the tropical tropopause layer (TTL). Some studies suggest that SVC has a significant impact on the earth radiation budget. The Costa Rica Aura Validation Experiment (CR-AVE) sponsored by the National Aeronautics and Space Administration (NASA) took place near San Jose, Costa Rica from 14 January–15 February 2006. The NASA WB-57F sampled S...