We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Relationships between Ice Water Content and Volume Extinction Coefficient from In Situ Observations for Temperatures from 0° to −86°C: Implications for Spaceborne Lidar Retrievals*.
- Authors
Heymsfield, Andrew; Winker, Dave; Avery, Melody; Vaughan, Mark; Diskin, Glenn; Deng, Min; Mitev, Valentin; Matthey, Renaud
- Abstract
An examination of 2 yr of Cloud-Aerosol Lidar Infrared Pathfinder Satellite Observations ( CALIPSO) lidar observations and CloudSat cloud radar observations shows that ice clouds at temperatures below about −45°C frequently fall below the CloudSat radar's detection threshold yet are readily detectable by the lidar. The CALIPSO ice water content (IWC) detection threshold is about 0.1 versus 5 mg m−3 for CloudSat. This comparison emphasizes the need for developing a lidar-only IWC retrieval method that is reliable for high-altitude ice clouds at these temperatures in this climatically important zone of the upper troposphere. Microphysical measurements from 10 aircraft field programs, spanning latitudes from the Arctic to the tropics and temperatures from −86° to 0°C, are used to develop relationships between the IWC and volume extinction coefficient σ in visible wavelengths. Relationships used to derive a radiatively important ice cloud property, the ice effective diameter D e, from σ are also developed. Particle size distributions (PSDs) and direct IWC measurements, together with evaluations of the ice particle shapes and comparisons with semidirect extinction measurements, are used in this analysis. Temperature-dependent D e( σ) and IWC- σ relationships developed empirically facilitate the retrieval of IWC from lidar-derived σ and D e values and for comparison with other IWC observations. This suite of empirically derived relationships can be expressed analytically. These relationships can be used to derive IWC and D e from σ and are developed for use in climate models to derive σ from prognosed values of IWC and specified PSD properties.
- Subjects
LIDAR; THERMODYNAMICS of clouds; ICE clouds; TROPOSPHERIC aerosols; TROPOSPHERE; PARTICLE size distribution
- Publication
Journal of Applied Meteorology & Climatology, 2014, Vol 53, Issue 2, p479
- ISSN
1558-8424
- Publication type
Article
- DOI
10.1175/JAMC-D-13-087.1