The profiles of marine boundary layer (MBL) cloud and drizzle microphysical properties are important for studying the cloud‐to‐rain conversion and growth processes in MBL clouds. However, it is challenging to simultaneously retrieve both cloud and drizzle microphysical properties within an MBL cloud layer using ground‐based observations. In this study, methods were developed to first decompose drizzle and cloud reflectivity in MBL clouds from Atmospheric Radiation Measurement cloud radar reflectivity measurements and then simultaneously retrieve cloud and drizzle microphysical properties during the Aerosol and Cloud Experiments in the Eastern North Atlantic (ACE‐ENA) campaign. These retrieved microphysical properties, such as cloud and drizzle particle size (
This paper presents a new retrieval method for inferring the vertical profile of cirrus cloud effective particle size by using solar reflected line spectra in the 1.38‐μm band. The retrieval method is based on the maximum‐photon penetration principle coupled with the constrained linear inversion. This approach takes advantage of the vertical stratification of cirrus cloud effective particle size as well as absorption lines of water vapor of different intensity, which contain rich information on the vertical structure of cloud particle size. Reflected radiances at different wavenumbers provide the effective‐size information at different heights within cirrus associated with photon different penetration depths. Assuming a vertical profile of effective size monotonically decreasing toward cloud top and using results based on “exact” radiative transfer computations, we perform retrieval of the effective size for a number of model cirrus to check for algorithm accuracy. The retrieved profile of effective size is close to the model profile for cirrus optical depth less than about eight with an uncertainty range of 2.2–4.2 μm. In addition, we further carry out a sensitivity study involving the retrieved effective size in connection with different water vapor profiles and demonstrate that the difference from the model is only several percent except for the cloud top if an appropriate wavenumber set is selected. The results from this study suggest that the present method can be applied to realistic remote sensing of the vertical profile of cirrus cloud particle size.
more » « less- NSF-PAR ID:
- 10375123
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Earth and Space Science
- Volume:
- 7
- Issue:
- 5
- ISSN:
- 2333-5084
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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