Measurement of cirrus cloud optical properties as validation for aircraft- and satellite-based cloud studies

Daniel H. DeSlover (Dave Turner, Ping Yang)University of Wisconsin - Madison

Cooperative Institute for Meteorological Satellite StudiesSpace Science and Engineering Center

MURI Workshop, 7-9 June 2005

Instrument Suite

Atmospheric State Measurements • NCAR Cross-chain Loran Sounding System (CLASS), Vaisala sondes

Aircraft (ER-2 or Proteus) Measurements • High spectral resolution FTS: NAST-I (NASA LaRC) or S-HIS (UW)

Surface Measurements • High spectral resolution FTS: Atmospheric Emitted Radiance Interferometer (AERI) • CART Micropulse Lidar (MPL), CART Raman Lidar (CARL), or High Spectral Resolution Lidar (HSRL)

Data Analysis Flow Chart:Absorption Optical Depth

Input data:

Radiosonde (atmospheric state)

Lidar (cloud boundaries)

FTS (emitted radiance)

Calculate clear sky transmittance for each radiosonde using LBLRTM

Interpolate temperature profile and transmittance profile to FTS time

Clear sky radiance and transmittanceto cloud base

Invert cloud absorption optical depth from FTS measurements and modeled clear sky LBLRTM calculations

AERI Measured Downwelling Radiance

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19

Cirrus Cloud Absorption Optical DepthYields Effective Particle Size Retrieval

AERI Measured Cirrus Particle Size Retrieval: 8 Dec 2000

AERI Measured Cirrus Particle Size Retrieval: 8 Dec 2000

AERI Absorption Optical Depth andTotal Optical Depth for Retrieved Size

Simulation Data Retrieval

GOES IR Imagery: 8 Dec 20000100 through 0245 UTC

Case Study, AFWEX 20008 Dec 2000

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NAST-I and AERI Measured Cirrus Spectral Optical Depth: 8 Dec 2000

Case Study, AFWEX 20008 Dec 2000

Case Study, AFWEX 20008 Dec 2000

Case Study, AFWEX 20008 Dec 2000

Case Study, AFWEX 20008 Dec 2000

Case Study, AFWEX 20008 Dec 2000

Case Study, TX200229 Nov 2002

Case Study, TX200229 Nov 2002: Four S-HIS Overpasses

Case Study, TX200229 Nov 2002: Four S-HIS Overpasses

Case Study, TX200229 Nov 2002: Rapid-sample AERI

Case Study, TX200229 Nov 2002: Rapid-sample AERI

Case Study, TX200229 Nov 2002: Rapid-sample AERI

Case Study, TX200229 Nov 2002: Rapid-sample AERI

Case Study, TX200229 Nov 2002: Rapid-sample AERI

Case Study, TX200229 Nov 2002: Rapid-sample AERI

Case Study, TX200229 Nov 2002: Rapid-sample AERI

Case Study, TX200229 Nov 2002: Rapid-scan AERI

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Summary, Future Work, and References

DeSlover, D. H., W. L. Smith, P. K. Piironen, and E. W. Eloranta (1999): A methodology for measuring cirrus cloud visible to infrared optical depth ratios. J. Atmos. Oceanic Technol., 16, pp. 251--262.

Smith, W. L., S. Ackerman, H. Revercomb, H. Huang, D. H. DeSlover, W. Feltz, L. Gumley, and A. Collard (1998): Infrared spectral absorption of nearly invisible cirrus clouds. Geophys. Res. Lett., 25, pp. 1137-1140.

High spectral resolution FTS measurements were used to infer cirrus cloud optical depth from both aircraft- and ground-based platforms,

• demonstrated good agreement for similar measurements above (NAST-I and S-HIS) and below (AERI) cloud,

• good correlation between ground-based AERI and Raman lidar,• rapid-sample AERI data greatly improves ability to resolve cloud features• same approach can be used to validate AIRS measurements from Aqua.

First attempt at particle size retrieval was successful for two case studies (AFWEX 2000 and TX2002).