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Title: Initialization and validation of a simulation of cirrus using FIRE-II data

Abstract

Observations from a wide variety of instruments and platforms are used to validate many different aspects of a three-dimensional mesoscale simulation of the dynamics, cloud microphysics, and radiative transfer of a cirrus cloud system observed on 26 November 1991 during the second cirrus field program of the First International Satellite Cloud Climatology Program (ISCCP) Regional Experiment (FIRE-II) located in southeastern Kansas. The simulation was made with a mesoscale dynamical model utilizing a simplified bulk water cloud scheme and a spectral model of radiative transfer. Expressions for cirrus optical properties for solar and infrared wavelength intervals as functions of ice water content and effective particle radius are modified for the midlatitude cirrus observed during FIRE-II and are shown to compare favorably with explicit size-resolving calculations of the optical properties. Rawinsonde, Raman lidar, and satellite data are evaluated and combined to produce a time-height cross section of humidity at the central FIRE-II site for model verification. Due to the wide spacing of rawinsondes and their infrequent release, important moisture features go undetected and are absent in the conventional analyses. The upper-tropospheric humidities used for the initial conditions were generally less than 50% of those inferred from satellite data, yet over the coursemore » of a 24-h simulation the model produced a distribution that closely resembles the large-scale features of the satellite analysis. The simulated distribution and concentration of ice compares favorably with data from radar, lidar satellite, and aircraft. Direct comparison is made between the radiative transfer simulation and data from broadband and spectral sensors and inferred quantities such as cloud albedo, optical depth, and top-of-the-atmosphere 11-{mu}m brightness temperature, and the 6.7-{mu}m brightness temperature. 49 refs., 26 figs., 1 tab.« less

Authors:
 [1];  [2]; ;  [3]
  1. Naval Research Lab., Monterey, CA (United States)
  2. NASA/Ames Research Center, Moffet Field, CA (United States)
  3. NASA/Langley Research Center, Hampton, VA (United States); and others
Publication Date:
OSTI Identifier:
466625
DOE Contract Number:  
AI05-90ER61074
Resource Type:
Journal Article
Journal Name:
Journal of the Atmospheric Sciences
Additional Journal Information:
Journal Volume: 53; Journal Issue: 23; Other Information: PBD: 1 Dec 1996
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; CLOUD COVER; COMPUTERIZED SIMULATION; KANSAS; VALIDATION; WATER VAPOR; ICE; PARTICLE SIZE; RADIANT HEAT TRANSFER

Citation Formats

Westphal, D L, Kinne, S, Alvarez, J M, and Minnis, P. Initialization and validation of a simulation of cirrus using FIRE-II data. United States: N. p., 1996. Web. doi:10.1175/1520-0469(1996)053<3397:IAVOAS>2.0.CO;2.
Westphal, D L, Kinne, S, Alvarez, J M, & Minnis, P. Initialization and validation of a simulation of cirrus using FIRE-II data. United States. https://doi.org/10.1175/1520-0469(1996)053<3397:IAVOAS>2.0.CO;2
Westphal, D L, Kinne, S, Alvarez, J M, and Minnis, P. 1996. "Initialization and validation of a simulation of cirrus using FIRE-II data". United States. https://doi.org/10.1175/1520-0469(1996)053<3397:IAVOAS>2.0.CO;2.
@article{osti_466625,
title = {Initialization and validation of a simulation of cirrus using FIRE-II data},
author = {Westphal, D L and Kinne, S and Alvarez, J M and Minnis, P},
abstractNote = {Observations from a wide variety of instruments and platforms are used to validate many different aspects of a three-dimensional mesoscale simulation of the dynamics, cloud microphysics, and radiative transfer of a cirrus cloud system observed on 26 November 1991 during the second cirrus field program of the First International Satellite Cloud Climatology Program (ISCCP) Regional Experiment (FIRE-II) located in southeastern Kansas. The simulation was made with a mesoscale dynamical model utilizing a simplified bulk water cloud scheme and a spectral model of radiative transfer. Expressions for cirrus optical properties for solar and infrared wavelength intervals as functions of ice water content and effective particle radius are modified for the midlatitude cirrus observed during FIRE-II and are shown to compare favorably with explicit size-resolving calculations of the optical properties. Rawinsonde, Raman lidar, and satellite data are evaluated and combined to produce a time-height cross section of humidity at the central FIRE-II site for model verification. Due to the wide spacing of rawinsondes and their infrequent release, important moisture features go undetected and are absent in the conventional analyses. The upper-tropospheric humidities used for the initial conditions were generally less than 50% of those inferred from satellite data, yet over the course of a 24-h simulation the model produced a distribution that closely resembles the large-scale features of the satellite analysis. The simulated distribution and concentration of ice compares favorably with data from radar, lidar satellite, and aircraft. Direct comparison is made between the radiative transfer simulation and data from broadband and spectral sensors and inferred quantities such as cloud albedo, optical depth, and top-of-the-atmosphere 11-{mu}m brightness temperature, and the 6.7-{mu}m brightness temperature. 49 refs., 26 figs., 1 tab.},
doi = {10.1175/1520-0469(1996)053<3397:IAVOAS>2.0.CO;2},
url = {https://www.osti.gov/biblio/466625}, journal = {Journal of the Atmospheric Sciences},
number = 23,
volume = 53,
place = {United States},
year = {1996},
month = {12}
}