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Title: Optical properties of shallow tropical cumuli derived from ARM ground-based remote sensing

Abstract

This paper presents results from ground-based remote sensing of optical properties of shallow convective clouds over the Nauru ARM site using the technique developed in McFarlane et al. (J. Geophys. Res. 2002). Herein, the results of a pilot study are presented with analysis of about six months of cloud data. The effective radius (re) shows large spatial variability, with the frequency of occurrence relatively narrow near the cloud base, and gradually widening aloft. Available column data for LWC and re allow derivation of the pdf of the optical thickness tau. The pdf shows that clouds with tau in the range 5 to 10 are most frequent, but there is a long tail with clouds up to tau = 100. These results are discussed in the context of traditional observations of cloud microstructure using an instrumented aircraft.

Authors:
;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
902040
Report Number(s):
PNNL-SA-53158
Journal ID: ISSN 0094-8276; GPRLAJ; KP1205010; TRN: US200716%%465
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Geophysical Research Letters, 34(6):Art. No. L06808; Journal Volume: 34; Journal Issue: 6
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; OPTICAL PROPERTIES; CLOUDS; NAURU; REMOTE SENSING

Citation Formats

McFarlane, Sally A., and Grabowski, Wojciech W. Optical properties of shallow tropical cumuli derived from ARM ground-based remote sensing. United States: N. p., 2007. Web. doi:10.1029/2006GL028767.
McFarlane, Sally A., & Grabowski, Wojciech W. Optical properties of shallow tropical cumuli derived from ARM ground-based remote sensing. United States. doi:10.1029/2006GL028767.
McFarlane, Sally A., and Grabowski, Wojciech W. Thu . "Optical properties of shallow tropical cumuli derived from ARM ground-based remote sensing". United States. doi:10.1029/2006GL028767.
@article{osti_902040,
title = {Optical properties of shallow tropical cumuli derived from ARM ground-based remote sensing},
author = {McFarlane, Sally A. and Grabowski, Wojciech W.},
abstractNote = {This paper presents results from ground-based remote sensing of optical properties of shallow convective clouds over the Nauru ARM site using the technique developed in McFarlane et al. (J. Geophys. Res. 2002). Herein, the results of a pilot study are presented with analysis of about six months of cloud data. The effective radius (re) shows large spatial variability, with the frequency of occurrence relatively narrow near the cloud base, and gradually widening aloft. Available column data for LWC and re allow derivation of the pdf of the optical thickness tau. The pdf shows that clouds with tau in the range 5 to 10 are most frequent, but there is a long tail with clouds up to tau = 100. These results are discussed in the context of traditional observations of cloud microstructure using an instrumented aircraft.},
doi = {10.1029/2006GL028767},
journal = {Geophysical Research Letters, 34(6):Art. No. L06808},
number = 6,
volume = 34,
place = {United States},
year = {Thu Mar 29 00:00:00 EDT 2007},
month = {Thu Mar 29 00:00:00 EDT 2007}
}
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