Warning message

Member access has been temporarily disabled. Please try again later.
The SEAC4RS website is undergoing a major upgrade that began Friday, October 11th at 5:00 PM PDT. The new upgraded site will be available no later than Monday, October 21st. Until that time, the current site will be visible but logins are disabled.

 

Disclaimer: This material is being kept online for historical purposes. Though accurate at the time of publication, it is no longer being updated. The page may contain broken links or outdated information, and parts may not function in current web browsers. Visit https://espo.nasa.gov for information about our current projects.

 

Derivation of physical and optical properties of mid-latitude cirrus ice...

Fridlind, A. M., R. Atlas, B. van Diedenhoven, J. Um, G. McFarquhar, A. S. Ackerman, E. J. Moyer, and P. Lawson (2016), Derivation of physical and optical properties of mid-latitude cirrus ice crystals for a size-resolved cloud microphysics model, Atmos. Chem. Phys., 16, 7251-7283, doi:10.5194/acp-16-7251-2016.
Abstract: 

Single-crystal images collected in mid-latitude cirrus are analyzed to provide internally consistent ice physical and optical properties for a size-resolved cloud microphysics model, including single-particle mass, projected area, fall speed, capacitance, single-scattering albedo, and asymmetry parameter. Using measurements gathered during two flights through a widespread synoptic cirrus shield, bullet rosettes are found to be the dominant identifiable habit among ice crystals with maximum dimension (Dmax ) greater than 100 µm. Properties are therefore first derived for bullet rosettes based on measurements of arm lengths and widths, then for aggregates of bullet rosettes and for unclassified (irregular) crystals. Derived bullet rosette masses are substantially greater than reported in existing literature, whereas measured projected areas are similar or lesser, resulting in factors of 1.5–2 greater fall speeds, and, in the limit of large Dmax , near-infrared single-scattering albedo and asymmetry parameter (g) greater by ∼ 0.2 and 0.05, respectively. A model that includes commonly imaged side plane growth on bullet rosettes exhibits relatively little difference in microphysical and optical properties aside from ∼ 0.05 increase in mid-visible g primarily attributable to plate aspect ratio. In parcel simulations, ice size distribution, and g are sensitive to assumed ice properties.

PDF of Publication: 
Download from publisher's website.
Research Program: 
Radiation Science Program (RSP)